Transducer automatic press and tighten tool

Abstract

The present application belongs to the technical field of ultrasonic transducer assembly equipment, and in particular to an automatic pressing and tightening tool for transducers. Through the cooperative work of the hydraulic pressing mechanism and the servo tightening mechanism, the bottom die is first driven by the hydraulic cylinder to press the transducer parts towards the top die, and the pressing pressure closed-loop control is realized in cooperation with the pressure sensor; then the wrench sleeve is tightened by the servo motor, and the tightening torque is detected in real time by the dynamic torque sensor, while the transducer performance parameters are collected in real time during the tightening process as the shutdown condition, effectively avoiding the performance influence of the relative displacement of the parts caused by the tightening of the bolts in the traditional process; multiple safety protections are realized through the double-hand starting button, the travel switch and the emergency stop button; the pressing pressure, the tightening torque and the transducer performance parameters are recorded by the control system to realize quality traceability; the whole machine layout is reasonable, the rigidity is good, the operation is convenient, and the consistency and the qualification rate of the transducer assembly are significantly improved.

Description

Technical Field

[0001] This invention relates to the field of ultrasonic transducer assembly equipment technology, specifically to an automatic transducer pressing and tightening fixture. Background Technology

[0002] Ultrasonic transducers are typically assembled by bolting together the components. Current processes rely solely on the axial force generated during bolt tightening to apply pressure to the parts, lacking a separate pre-compression step. Because of friction and rotational torque between the threaded pairs during bolt tightening, slight relative displacement or deflection can easily occur between the components, leading to poor consistency in the transducer's electrical performance parameters (such as resonant frequency and impedance), thus affecting product yield. Furthermore, the required compression force and tightening torque vary significantly between transducers of different specifications, making precise control difficult with traditional methods, easily resulting in component damage or poor assembly.

[0003] Therefore, we propose an automatic transducer pressing and tightening fixture to solve the above problems. Summary of the Invention

[0004] (a) Technical problems to be solved

[0005] To address the shortcomings of existing technologies, this invention provides an automatic transducer pressing and tightening fixture, which solves the problem mentioned in the background art that relying solely on bolt tightening for pressure in existing transducer assembly processes can easily lead to relative displacement between parts, affecting product performance and consistency.

[0006] (II) Technical Solution

[0007] To achieve the above objectives, the present invention specifically adopts the following technical solution:

[0008] An automatic transducer pressing and tightening fixture includes:

[0009] Rack components;

[0010] The hydraulic pressing mechanism is provided on the frame assembly. The hydraulic pressing mechanism includes a top mold and a bottom mold arranged opposite each other, a hydraulic cylinder that drives the bottom mold to move toward the top mold, and a pressure sensor for detecting the pressing pressure.

[0011] The servo tightening mechanism is located above the hydraulic pressing mechanism. The servo tightening mechanism includes a wrench for tightening bolts, a servo motor for driving the wrench to rotate, and a dynamic torque sensor for detecting tightening torque.

[0012] Furthermore, the frame assembly includes a lower frame, which is a stepped combination of a lower platform and an upper platform; the hydraulic pressing mechanism and the servo tightening mechanism constitute a pressing and tightening component and are disposed on the lower platform, and a touch screen assembly is also disposed on the lower platform; a hydraulic pump is disposed inside the upper platform.

[0013] Furthermore, the hydraulic pressing mechanism also includes a platform fixed to the frame assembly, a base plate fixed above the platform, a plurality of guide columns vertically arranged on the base plate, a top plate fixed to the top of each guide column, and a middle template slidably sleeved on each guide column via linear bearings.

[0014] The top mold is detachably installed at the bottom of the top plate, and the bottom mold is installed at the top of the middle mold plate; the hydraulic cylinder is installed at the bottom of the platform, and the output end of the hydraulic cylinder passes through the platform and is connected to the bottom of the middle mold plate through a pressure sensor; an instrument storage platform is provided on the top of the platform.

[0015] Furthermore, the hydraulic pressing mechanism also includes a contact plate mounting rod disposed on one side of the middle template, and the contact plate mounting rod is provided with two limit switch contact plates respectively located above and below the middle template; limit switches are respectively disposed on one side of the bottom plate and the top plate; when the middle template rises or falls to the limit position, the corresponding limit switch contact plate triggers the limit switch.

[0016] Furthermore, the servo tightening mechanism also includes a guide shaft connecting plate, a plurality of guide shafts vertically arranged at the bottom of the guide shaft connecting plate, a reducer mounting plate slidably sleeved on each of the guide shafts via linear bearings, and a support mounting plate slidably sleeved on each of the guide shafts via linear bearings.

[0017] The top of the support mounting plate is provided with a support base; the servo motor is mounted on the reducer mounting plate via a reducer; the two ends of the dynamic torque sensor are respectively connected to the output end of the reducer and a tightening spindle via a first coupling and a second coupling; the tightening spindle is rotatably supported inside the support base and its bottom end is connected to a wrench sleeve; the guide shaft connecting plate is provided with clearance holes inside.

[0018] Furthermore, the servo tightening mechanism also includes two connecting plates fixedly connected between the reducer mounting plate and the support mounting plate. The two connecting plates are arranged opposite to each other, and a reinforcing rib and a sensor mounting plate for mounting a dynamic torque sensor are respectively provided between the two connecting plates.

[0019] Furthermore, both the bottom end of the tightening spindle and the top end of the wrench socket are provided with square structures. The interior of the connecting sleeve has a square hole that matches the square structure. The tightening spindle and the connecting sleeve, as well as the connecting sleeve and the wrench socket, transmit circumferential torque through the cooperation of the square structure and the square hole. The top end of the connecting sleeve is axially limited to the tightening spindle by a first pin. The top end of the wrench socket is inserted into the connecting sleeve and has an oblong hole. The connecting sleeve and the wrench socket are connected by a second pin that passes through the oblong hole. The second pin cooperates with the oblong hole to allow the wrench socket to float axially relative to the connecting sleeve. At the same time, the second pin provides axial limitation for the wrench socket.

[0020] Furthermore, the servo tightening mechanism also includes a lifting adjustment component for adjusting the working height of the servo motor. The lifting adjustment component includes a trapezoidal lead screw rotatably mounted on the guide shaft connecting plate, a lead screw nut fixed on the reducer mounting plate, and a handwheel located at the top of the trapezoidal lead screw. The trapezoidal lead screw and the lead screw nut are connected in cooperation.

[0021] Furthermore, a quick-release structure is provided between the top plate and the top mold. The quick-release structure includes two L-shaped tracks symmetrically fixed to the bottom of the top plate, forming a T-shaped installation space between the two L-shaped tracks. The top mold is slidably engaged within the T-shaped installation space.

[0022] Furthermore, the servo tightening mechanism also includes a U-shaped photoelectric switch disposed at the bottom of the support mounting plate and a sensing plate fixed on the tightening spindle. The U-shaped photoelectric switch and the sensing plate cooperate to position the servo motor back to its origin.

[0023] (III) Beneficial Effects

[0024] Compared with the prior art, the present invention provides an automatic transducer pressing and tightening fixture, which has the following beneficial effects:

[0025] This invention utilizes the coordinated operation of a hydraulic pressing mechanism and a servo tightening mechanism. First, a hydraulic cylinder drives the bottom mold to press the transducer parts towards the top mold, and a pressure sensor enables closed-loop control of the pressing pressure. Then, a servo motor drives a wrench to tighten the bolts, and a dynamic torque sensor monitors the tightening torque in real time. Simultaneously, transducer performance parameters are collected in real time during the tightening process as stop conditions, effectively avoiding the performance impact caused by relative displacement of parts due to bolt tightening in traditional processes. Multiple safety protections are provided through two-hand start buttons, limit switches, and an emergency stop button. The control system records the pressing pressure, tightening torque, and transducer performance parameters, enabling quality traceability. The machine has a reasonable layout, good rigidity, and is easy to operate, significantly improving the consistency and pass rate of transducer assembly. Attached Figure Description

[0026] Figure 1This is a schematic diagram of the rack assembly structure of the present invention;

[0027] Figure 2 This is a schematic diagram of the hydraulic pump structure of the present invention;

[0028] Figure 3 This is a schematic diagram of the hydraulic pressing mechanism and servo tightening mechanism of the present invention;

[0029] Figure 4 This is a schematic diagram of the hydraulic pressing mechanism and servo tightening mechanism of the present invention;

[0030] Figure 5 This is a cross-sectional view of the hydraulic pressing mechanism and servo tightening mechanism of the present invention;

[0031] Figure 6 This is a cross-sectional view of the servo tightening mechanism of the present invention;

[0032] Figure 7 This is a cross-sectional view of the hydraulic pressing mechanism of the present invention.

[0033] In the diagram: 1. Frame assembly; 11. Lower frame; 12. Touch screen assembly; 13. Hydraulic pump; 2. Hydraulic pressing mechanism; 21. Top mold; 22. Bottom mold; 23. Hydraulic cylinder; 24. Pressure sensor; 25. Tabletop; 251. Base plate; 252. Guide column; 253. Double-hole button box; 26. Top plate; 261. L-shaped track; 27. Middle template; 271. Contact plate mounting rod; 272. Limit switch contact plate; 28. Instrument storage platform; 29. ​​Limit switch; 3. Servo tightening mechanism; 31. Wrench sleeve; 311. Waist-shaped hole; 32. Servo motor; 321. Reducer; 33. Dynamic torque sensor; 331. 332. First coupling; 34. Second coupling; 35. Guide shaft connecting plate; 36. Guide shaft; 37. Clearance hole; 38. Reducer mounting plate; 39. Connecting vertical plate; 30. Reinforcing rib; 31. Sensor mounting plate; 32. Cable support plate; 33. Support base mounting plate; 34. Support base; 35. U-groove photoelectric switch; 36. Tightening spindle; 37. Sensing plate; 38. Connecting sleeve; 39. First pin; 30. Second pin; 31. Lifting adjustment assembly; 32. Trapezoidal lead screw; 33. Lead screw nut; 34. Handwheel; 35. Lead screw support; 36. Clamping limit seat; 37. Handle. Detailed Implementation

[0034] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0035] Example

[0036] like Figure 1-7 As shown, an embodiment of the present invention provides an automatic transducer pressing and tightening fixture, comprising:

[0037] Rack assembly 1;

[0038] The hydraulic pressing mechanism 2 is provided on the frame assembly 1. The hydraulic pressing mechanism 2 includes a top mold 21 and a bottom mold 22 arranged opposite to each other, a hydraulic cylinder 23 that drives the bottom mold 22 to move toward the top mold 21, and a pressure sensor 24 for detecting the pressing pressure.

[0039] The servo tightening mechanism 3 is located above the hydraulic pressing mechanism 2. The servo tightening mechanism 3 includes a wrench sleeve 31 for tightening bolts, a servo motor 32 for driving the wrench sleeve 31 to rotate, and a dynamic torque sensor 33 for detecting tightening torque.

[0040] In some embodiments, the transducer automatic pressing and tightening fixture further includes an electrical control system.

[0041] like Figure 1-7 As shown, in some embodiments, the rack assembly 1 includes a lower rack 11, which is a stepped combination of a lower platform and an upper platform; the hydraulic pressing mechanism 2 and the servo tightening mechanism 3 constitute a pressing and tightening component and are disposed on the lower platform; the lower platform is also provided with a touch screen assembly 12; and the upper platform is internally provided with a hydraulic pump 13.

[0042] The frame assembly 1 includes a lower frame 11, which consists of a lower platform and an upper platform arranged in a stepped configuration. A pressing and tightening component, consisting of a hydraulic pressing mechanism 2 and a servo tightening mechanism 3, is located on the lower platform. A touchscreen assembly 12 is also installed on the lower platform to display and set process parameters such as pressing pressure and tightening torque, and provides alarm functions (e.g., a buzzer). A hydraulic pump 13 is installed inside the upper platform. The hydraulic pump 13 includes an oil tank, a pump, a solenoid valve, a motor, and connecting pipes. The oil tank stores hydraulic oil, and the motor-driven pump draws hydraulic oil from the tank, which is then delivered to the hydraulic cylinder 23 via the solenoid valve and pipes. The control system controls the rising, pressure-holding, and lowering actions of the hydraulic cylinder 23 by controlling the opening, closing, and reversing of the solenoid valve. Furthermore, an oil collection box is located on one side of the lower platform to collect any spilled oil from the hydraulic cylinder 23, keeping the work surface clean.

[0043] By setting the lower frame 11 as a stepped, double-layer platform structure, the hydraulic pump 13 and the pressing and tightening components are separated vertically. This saves lateral space occupied by the tooling and isolates the vibration source of the hydraulic pump 13 from the precision pressing and tightening components, preventing the vibration of the hydraulic pump 13 from being transmitted to the pressing and tightening components, thereby improving the accuracy of pressing and tightening. Meanwhile, the touch screen component 12 integrates human-machine interaction and alarm functions, allowing operators to intuitively monitor and set process parameters, and a buzzer can promptly alert the operator in case of abnormalities. The oil collection box effectively collects any hydraulic oil that may leak from the hydraulic cylinder 23, keeping the workbench and floor clean, meeting environmental protection and production site management requirements.

[0044] like Figure 1-7 As shown, in some embodiments, the hydraulic pressing mechanism 2 further includes a platform 25 fixed to the frame assembly 1, a base plate 251 fixed above the platform 25, a plurality of guide columns 252 (four in this embodiment) vertically arranged on the base plate 251, a top plate 26 fixed to the top of each guide column 252, and a middle template 27 slidably sleeved on each guide column 252 via linear bearings;

[0045] The top mold 21 is detachably installed at the bottom of the top plate 26, and the bottom mold 22 is installed at the top of the middle mold plate 27; the hydraulic cylinder 23 is installed at the bottom of the platform 25, and the output end of the hydraulic cylinder 23 passes through the platform 25 and is connected to the bottom of the middle mold plate 27 through the pressure sensor 24; the top of the platform 25 is provided with an instrument storage platform 28 for placing transducer-specific testing instruments, which facilitates the operator to connect the testing line.

[0046] When the hydraulic cylinder 23 lifts upward, its output end pushes the middle template 27 through the pressure sensor 24, causing the middle template 27 to rise smoothly along the four guide columns 252 using linear bearings. The bottom mold 22, fixed to the middle template 27, rises accordingly, pressing the transducer components placed on the bottom mold 22 upward toward the top mold 21. During this process, the pressure sensor 24 detects the pressing force in real time and converts it into an electrical signal, which is then fed back to the control system. When the pressing force reaches a preset pressure range, the control system controls the hydraulic pump 13 to stop supplying pressure, and the hydraulic cylinder 23 maintains the current pressure and holds it. The cooperation between the four guide columns 252 and the linear bearings ensures that the middle template 27 remains horizontal during the lifting process, without tilting or swaying. The top mold 21 is detachably installed at the bottom of the top plate 26, facilitating quick replacement of the top mold 21 according to different transducer specifications. The instrument platform 28 directly integrates the transducer testing instrument onto the tooling, allowing the testing cable to be easily connected to the transducer without the need for additional supports.

[0047] The pressure sensor 24, in conjunction with the hydraulic cylinder 23, achieves closed-loop control of the pressing pressure, ensuring that the pressure value for each pressing operation remains within the preset range and consistent. This guarantees a tight fit between transducer components while preventing damage due to excessive pressure. The four guide columns 252 and the linear bearing guide structure provide excellent rigidity to the middle mold plate 27 during its ascent, preventing off-center loading and swaying during the pressing process. This ensures the parallelism between the top mold 21 and the bottom mold 22, guaranteeing uniform pressing of the transducer components. The detachable installation method of the top mold 21 allows the operator to quickly replace it without tools, enabling the same fixture to accommodate various transducer specifications. The instrument platform 28 places the testing instrument nearby, shortening the length of the testing cable, avoiding cable tangling, facilitating operator operation, and improving assembly efficiency.

[0048] like Figure 1-7 As shown, in some embodiments, the hydraulic pressing mechanism 2 further includes a contact plate mounting rod 271 disposed on one side of the middle template 27, and the contact plate mounting rod 271 is provided with two limit switch contact plates 272 respectively located above and below the middle template 27; limit switches 29 are respectively disposed on one side of the bottom plate 251 and the top plate 26; when the middle template 27 rises or falls to the limit position, the corresponding limit switch contact plate 272 triggers the limit switch 29.

[0049] When the middle template 27 rises or falls to its limit position, the corresponding limit switch contact plate 272 triggers the limit switch 29, and the limit switch 29 then sends an electrical signal to the control system, which immediately stops the action of the hydraulic cylinder 23.

[0050] The contact plate mounting rod 271 is fixed to the side of the middle template 27 and moves synchronously with the middle template 27. The upper limit switch contact plate 272 mounted on this rod is located above the middle template 27, and the lower limit switch contact plate 272 is located below the middle template 27. When the hydraulic cylinder 23 drives the middle template 27 to rise to a position close to the safety limit of the top plate 26, the upper limit switch contact plate 272 contacts the limit switch 29 mounted on one side of the top plate 26, triggering the limit switch 29. The control system then cuts off the oil supply circuit for the hydraulic cylinder 23 to rise. Similarly, when the middle template 27 descends to a position close to the limit of the bottom plate 251, the lower limit switch contact plate 272 triggers the limit switch 29 on the bottom plate 251, and the hydraulic cylinder 23 stops descending.

[0051] The contact plate 272 and the limit switch 29 work together to provide mechanical soft limit protection for the movement of the hydraulic cylinder 23, independent of the pressure sensor 24. Even if the pressure sensor 24 or the control system malfunctions, the limit switch 29 can still forcibly stop the hydraulic cylinder 23 when the middle mold plate 27 moves to a dangerous position, preventing the hydraulic cylinder 23 from over-pressing and damaging the top mold 21, bottom mold 22, or transducer parts, while also preventing the hydraulic cylinder 23 from excessively retracting and causing mechanical collisions. This dual protection mechanism significantly improves the safety and reliability of the equipment.

[0052] The limit switch contact plate 272 is secured to the contact plate mounting rod 271 by screws or other fasteners, and the installation position is adjustable.

[0053] like Figure 1-7 As shown, in some embodiments, the servo tightening mechanism 3 further includes a guide shaft connecting plate 34, a plurality of guide shafts 341 vertically disposed at the bottom of the guide shaft connecting plate 34, a reducer mounting plate 35 slidably sleeved on each of the guide shafts 341 via linear bearings, and a support mounting plate 36 slidably sleeved on each of the guide shafts 341 via linear bearings.

[0054] The top of the support mounting plate 36 is provided with a support base 361; the servo motor 32 is mounted on the reducer mounting plate 35 via a reducer 321; the two ends of the dynamic torque sensor 33 are respectively connected to the output end of the reducer 321 and a tightening spindle 37 via a first coupling 331 and a second coupling 332; the tightening spindle 37 is rotatably supported inside the support base 361 and its bottom end is connected to a wrench sleeve 31; the guide shaft connecting plate 34 is provided with a clearance hole 342 inside, which is used for the top of the servo motor 32 and the reducer 321 to pass through; the bottom end of the guide shaft 341 is fixedly connected to the top plate 26.

[0055] The rotational torque output by the servo motor 32 is amplified by the reducer 321 and then transmitted to the dynamic torque sensor 33 via the first coupling 331. The dynamic torque sensor 33 then transmits the torque to the tightening spindle 37 via the second coupling 332. The tightening spindle 37 rotates inside the support 361, causing the wrench sleeve 31 at its bottom to rotate, thereby tightening the bolts on the transducer. The dynamic torque sensor 33 detects the torque value in real time during the torque transmission process and feeds it back to the control system. The reducer mounting plate 35 can slide up and down along the guide shaft 341 via linear bearings, and the support mounting plate 36 can also slide up and down along the guide shaft 341 via linear bearings. The clearance hole 342 on the guide shaft connecting plate 34 allows the tops of the servo motor 32 and the reducer 321 to extend upwards, thereby reducing the overall height dimension of the machine.

[0056] By setting an independent dynamic torque sensor 33 between the servo motor 32 and the tightening spindle 37, real-time and accurate detection of the tightening torque is achieved. This detection accuracy is significantly higher than the torque value calculated by the servo motor 32 itself through current feedback, thus enabling more accurate control of the tightening process and preventing excessive torque from damaging the transducer's threads or parts. The structure where both the reducer mounting plate 35 and the support mounting plate 36 can slide along the guide shaft 341 allows the height of the entire tightening assembly to be adjusted to accommodate transducers of different heights. The clearance hole 342 allows the top of the servo motor 32 to extend upwards through the guide shaft connecting plate 34, resulting in a compact structure, reduced overall tooling height, and easier operator observation and operation.

[0057] like Figure 1-7 As shown, in some embodiments, the servo tightening mechanism 3 further includes two connecting plates 351 fixedly connected between the reducer mounting plate 35 and the support mounting plate 36. The two connecting plates 351 are arranged opposite to each other, and a reinforcing rib plate 352 and a sensor mounting plate 353 for mounting the dynamic torque sensor 33 are respectively provided between the two connecting plates 351.

[0058] The upper ends of the two connecting uprights 351 are fixedly connected to the reducer mounting plate 35, and the lower ends are fixedly connected to the support mounting plate 36, connecting the reducer mounting plate 35 and the support mounting plate 36 into an integral frame that can be raised and lowered synchronously. A reinforcing rib 352 is fixed between the two connecting uprights 351, increasing the torsional rigidity of the entire frame. The housing of the dynamic torque sensor 33 is fixed to the connecting uprights 351 or the reinforcing rib 352 via the sensor mounting plate 353, keeping the sensor body stationary while only the internal torque transmission components rotate.

[0059] The reducer mounting plate 35 and the support mounting plate 36 are fixedly connected to the connecting plate 351 to form an integral frame structure, and the frame is raised and lowered along the guide shaft 341 as a whole. This ensures the coaxiality of the servo motor 32 axis, the dynamic torque sensor 33 axis, and the tightening spindle 37 axis, reducing the additional torque caused by axis deviation. The reinforcing rib 352 significantly enhances the torsional rigidity of the connecting plate 351, preventing the connecting plate 351 from twisting and deforming when tightening high-torque bolts, thereby ensuring the stability of torque transmission and the accuracy of detection data. The dynamic torque sensor 33 is fixed to the connecting plate 351 by the sensor mounting plate 353, preventing the sensor housing from rotating with the spindle and ensuring the long-term stability and service life of the sensor.

[0060] like Figure 1-7 As shown, in some embodiments, the bottom end of the tightening spindle 37 and the top end of the wrench sleeve 31 are both provided with square structures, and the interior of the connecting sleeve 38 has square holes that mate with the square structures. During assembly, the square structures at the bottom end of the tightening spindle 37 and the top end of the wrench sleeve 31 are inserted into the square holes of the connecting sleeve 38, and circumferential torque is transmitted through the mating of the square structures and square holes. The pin only serves as an axial limiter and does not participate in torque transmission. The top end of the connecting sleeve 38 is axially limited to the tightening spindle 37 by a first pin 381, and a gap is left between the first pin 381 and the corresponding hole on the connecting sleeve 38 to prevent the tightening spindle 37 from falling out of the connecting sleeve 38. The top end of the wrench sleeve 31 is inserted into the connecting sleeve 38 and has an oblong hole 311. The connecting sleeve 38 and the wrench sleeve 31 are connected by a second pin 382 passing through the oblong hole 311. The second pin 382 cooperates with the oblong hole 311 to allow the wrench sleeve 31 to float axially relative to the connecting sleeve 38. At the same time, the second pin 382 axially limits the wrench sleeve 31 to prevent it from falling out of the connecting sleeve 38. The clearance fit between the second pin 382 and the oblong hole 311 allows the wrench sleeve 31 to slide freely during floating, but it never participates in torque transmission.

[0061] When the main shaft 37 rotates, the square structure and the square hole drive the connecting sleeve 38 to rotate synchronously. The connecting sleeve 38 then drives the wrench sleeve 31 to rotate synchronously through the square hole and the square structure at the top of the wrench sleeve 31. When the wrench sleeve 31 is inserted into the transducer bolt during descent, if there is a slight offset between the center of the wrench sleeve 31 and the center of the bolt, the wrench sleeve 31 can adaptively adjust relative to the connecting sleeve 38 in the axial direction (up and down). The oblong hole 311 provides a floating stroke for this adjustment. The second pin 382 can slide up and down in the oblong hole 311, but always provides axial restraint for the wrench sleeve 31 to prevent it from falling off.

[0062] The torque is transmitted through the square hole inside the connecting sleeve 38, which cooperates with the square structure on the tightening spindle 37 and the wrench sleeve 31. This design provides strong load-bearing capacity, allowing for high-torque tightening without slippage or damage. The wrench sleeve 31, through the cooperation of the connecting sleeve 38, the first pin 381, the second pin 382, ​​and the oblong hole 311, possesses axial floating capability, achieving automatic flexible alignment between the wrench sleeve 31 and the bolt. This structure reduces the accuracy requirements for transducer placement and avoids rigid alignment caused by part positioning deviations—rigid alignment can damage the bolt head or the wrench sleeve 31. Simultaneously, during tightening, this floating structure can adapt to changes in bolt height during screwing, maintaining appropriate clamping force. This structure is simple and reliable, significantly improving the tightening success rate and tooling tolerance.

[0063] like Figure 1-7 As shown, in some embodiments, the servo tightening mechanism 3 further includes a lifting adjustment component 39 for adjusting the working height of the servo motor 32. The lifting adjustment component 39 includes a trapezoidal lead screw 391 rotatably mounted on the guide shaft connecting plate 34, a lead screw nut 392 fixed on the reducer mounting plate 35, and a handwheel 393 located at the top of the trapezoidal lead screw 391. The trapezoidal lead screw 391 is connected to the lead screw nut 392. The handle 396 is used to lock the trapezoidal lead screw 391 after the height adjustment is completed to prevent the lead screw from rotating on its own during operation.

[0064] The lifting adjustment assembly 39 also includes a lead screw support 394, a clamping limit seat 395, and a handle 396; the lead screw support 394 is fixedly installed on the guide shaft connecting plate 34, and the trapezoidal lead screw 391 is rotatably disposed inside the guide shaft connecting plate 34 through the lead screw support 394, that is, the trapezoidal lead screw 391 can rotate freely relative to the guide shaft connecting plate 34 but is limited in the axial direction, and the trapezoidal lead screw 391 passes through the lead screw nut 392 and forms a threaded engagement with the lead screw nut 392.

[0065] When the operator turns the handwheel 393, the trapezoidal lead screw 391 can rotate synchronously. Since the lead screw nut 392 is fixed on the reducer mounting plate 35, when the trapezoidal lead screw 391 rotates, the lead screw nut 392 will generate relative movement along the axial direction of the trapezoidal lead screw 391, thereby driving the reducer mounting plate 35 and the entire tightening frame (including the connecting vertical plate 351, the support mounting plate 36, etc.) fixed thereto to move up and down along the guide shaft 341, so as to realize the adjustment of the working height of the wrench sleeve 31.

[0066] A clamping and limiting seat 395 is provided on the top of the guide shaft connecting plate 34. The clamping and limiting seat 395 is sleeved on the outside of the trapezoidal screw 391, and its structure is similar to that of a conventional clamp. The handle 396 is installed on the clamping and limiting seat 395, and operating the handle 396 can control the clamping and limiting seat 395 to clamp and release the trapezoidal screw 391. After the operator completes the height adjustment, he turns the handle 396 to make the clamping and limiting seat 395 clamp the trapezoidal screw 391, and uses friction to lock the trapezoidal screw 391, preventing the trapezoidal screw 391 from rotating on its own due to equipment vibration or torque reaction force during subsequent tightening operations, thereby ensuring that the working height of the tightening assembly remains stable.

[0067] The lifting and adjusting mechanism, composed of a handwheel 393, a trapezoidal lead screw 391, and a lead screw nut 392, allows the operator to quickly and effortlessly adjust the initial working height of the servo tightening assembly without the need for any tools, thus flexibly adapting to transducers of different height specifications. The lead screw support 394 provides stable rotational support for the trapezoidal lead screw 391, ensuring coaxiality and stability during rotation. The locking method using a clamping limit seat 395 and a handle 396 offers advantages over ordinary nut locking: faster operation, greater locking force, and no damage to the trapezoidal lead screw 391. The operator only needs to turn the handle 396 for reliable locking, requiring no additional tools. After locking, the clamping limit seat 395 and the trapezoidal lead screw 391 are in surface contact, preventing damage to the lead screw threads. This lifting and adjusting assembly 39 is compact, easy to operate, and reliably locked, making it particularly suitable for production scenarios requiring frequent switching between different transducer specifications, significantly improving the equipment's applicability and operational efficiency.

[0068] like Figure 1-7 As shown, in some embodiments, a quick-release structure is provided between the top plate 26 and the top mold 21. The quick-release structure includes two L-shaped rails 261 symmetrically fixed to the bottom of the top plate 26, and a T-shaped installation space is formed between the two L-shaped rails 261. The top mold 21 is slidably engaged in the T-shaped installation space.

[0069] The top of the top mold 21 is machined with a flange that matches the T-shaped installation space. The top mold 21 is pushed in from one end of the T-shaped installation space. The flange is limited by the L-shaped track 261. The working surface of the top mold 21 is exposed downward between the two L-shaped tracks 261. The limiting of the mold in the horizontal sliding direction (i.e. the direction of pushing in and pulling out) is completed by the cooperation of the tightening spindle 37 and the wrench sleeve 31.

[0070] When the top mold 21 needs to be installed, the operator first raises the servo tightening mechanism 3 using handwheel 393, causing the wrench sleeve 31 to move upwards out of the installation area of ​​the top plate 26. Then, the operator aligns the flange of the top mold 21 with the opening end of the T-shaped installation space formed by the two L-shaped tracks 261, and pushes the top mold 21 into place horizontally. Subsequently, the operator lowers the servo tightening mechanism 3 using handwheel 393, causing the wrench sleeve 31 to move downwards into the top mold 21. At this point, the wrench sleeve 31 occupies the space where the top mold 21 can be withdrawn laterally, and the top mold 21 is mechanically locked within the T-shaped installation space, preventing it from sliding out horizontally.

[0071] When it is necessary to disassemble the top mold 21, the operator first raises the servo tightening mechanism 3 by using the handwheel 393, so that the wrench sleeve 31 is completely pulled upward out of the top mold 21, releasing the horizontal lock on the top mold 21. Then, the operator pulls the top mold 21 out of the T-shaped installation space in the horizontal direction to complete the disassembly.

[0072] The L-shaped track 261 provides a vertical limit to the flange of the top mold 21, preventing the top mold 21 from falling off; tightening the main shaft 37 and the wrench sleeve 31 provides a horizontal limit, preventing the top mold 21 from accidentally slipping out during operation. The two work together to reliably lock the top mold 21 under normal operating conditions.

[0073] The T-shaped mounting space formed by the L-shaped rail 261, along with the interlocking engagement of the tightening spindle 37 / wrench sleeve 31, enables rapid disassembly and assembly of the top mold 21, along with dual locking. Operators can replace the top mold 21 within seconds without using any tools, significantly reducing mold change time and improving equipment utilization. Simultaneously, this quick-release structure fully utilizes the existing tightening spindle 37 as a horizontal locking device for the top mold 21, eliminating the need for additional locking mechanisms; the structure is simple, compact, and low-cost. More importantly, under normal operating conditions, the wrench sleeve 31, inserted into the top mold 21, naturally forms an anti-disengagement lock, preventing accidental slippage even during equipment vibration, ensuring high safety. After repeated disassembly and assembly, the high positioning accuracy of the L-shaped rail 261 ensures the top mold 21 maintains a consistent working position, eliminating the need for recalibration.

[0074] like Figure 1-7 As shown, in some embodiments, the servo tightening mechanism 3 further includes a U-shaped photoelectric switch 362 disposed at the bottom of the support mounting plate 36 and a sensing plate 371 fixed on the tightening spindle 37. The U-shaped photoelectric switch 362 and the sensing plate 371 cooperate to position the servo motor 32 back to the origin.

[0075] like Figure 1-7As shown, in some embodiments, two double-hole button boxes 253 are provided on the top side of the platform 25. Each double-hole button box 253 has a start button, and the double-hole button box 253 closer to the operating position also has an emergency stop button. The installation distance between the two start buttons is greater than the shoulder width of an adult. The operator must press both start buttons simultaneously with both hands. The control system will only activate the hydraulic cylinder 23 after receiving both start signals. The emergency stop button is used to immediately cut off the power to the equipment in an emergency.

[0076] The dual-hole button box 253 and the two-hand start design force the operator to keep both hands away from the pressing area when starting the equipment, effectively preventing crushing accidents caused by the other hand being in a dangerous area during single-handed operation. The emergency stop button provides a quick way to stop the machine in emergencies, ensuring the operator's personal safety.

[0077] like Figure 1-7 As shown, in some embodiments, a cable support plate 354 is also provided on one side of the connecting plate 351 of the servo tightening mechanism 3. The cable support plate 354 has multiple cable fixing holes or cable tie holes for fixing and guiding the power cable of the servo motor 32, the signal cable of the dynamic torque sensor 33, and the cable of the photoelectric switch.

[0078] The cable support plate 354 can prevent the cable from sagging, getting tangled, or interfering with moving parts during the lifting and lowering movement of the reducer mounting plate 35 and the support mounting plate 36, thus avoiding cable wear and signal interference and improving the electrical reliability and cleanliness of the equipment.

[0079] like Figure 1-7 As shown, in some embodiments, the control system includes a programmable logic controller (PLC), a touch screen, and a switching power supply. The PLC is electrically connected to the pressure sensor 24, dynamic torque sensor 33, limit switch 29, U-slot photoelectric switch 362, and the start and emergency stop buttons on the double-hole button box, respectively, to collect the detection signals and operation commands from each sensor. The PLC is also electrically connected to the solenoid valve of the hydraulic pump 13, the driver of the servo motor 32, and a buzzer, respectively, to control the movement of the hydraulic cylinder 23, the start / stop and speed of the servo motor 32, and to issue an alarm in case of abnormalities. The touch screen has a bidirectional communication connection with the PLC, used to set the pressing pressure range, tightening torque range, and transducer performance parameter thresholds, and to display the equipment operating status and process data in real time. The switching power supply provides operating voltage to all components of the control system. The output of a dedicated transducer testing instrument is connected to the PLC. The PLC reads the electrical performance parameters of the transducer in real time and compares them with the set target range. When the parameters reach the set range, it controls the servo motor 32 to stop.

[0080] In operation, the operator first raises the servo tightening assembly using handwheel 393, causing the wrench sleeve 31 to move upwards out of the mounting area of ​​the top plate 26. Then, a suitable top mold 21 is selected and pushed into the bottom of the top plate 26 along the L-shaped track 261 to complete the installation. Next, the servo tightening assembly is lowered using handwheel 393, causing the wrench sleeve 31 to move downwards into the top mold 21 for locking. Finally, according to the transducer specifications, the initial working height of the servo tightening assembly is fine-tuned using handwheel 393 and trapezoidal screw 391, and a matching bottom mold 22 is selected and fixed onto the middle mold plate 27. The operator sets the required pressing pressure range, tightening torque range, and performance parameter thresholds (such as resonant frequency and impedance) required by the transducer-specific testing instruments on the touchscreen.

[0081] The operator places the pre-assembled transducer (with bolts in place but not yet tightened) into the positioning groove on the bottom mold 22 and connects the cable of the transducer-specific testing instrument to the corresponding electrode of the transducer. At this time, the hydraulic cylinder 23 is in the retracted state, and the middle mold plate 27 is located below.

[0082] The operator places both hands on two double-button boxes and presses both start buttons simultaneously. Upon receiving the two start signals, the control system activates hydraulic pump 13, switches the solenoid valve to the rising circuit, and the output end of hydraulic cylinder 23 begins to slowly rise. Hydraulic cylinder 23 pushes the middle mold plate 27 via pressure sensor 24, causing it to rise smoothly along the four guide columns 252. The bottom mold 22, fixed to the middle mold plate 27, lifts the transducer along with it. When the top of the transducer contacts the bottom surface of the top mold 21, hydraulic cylinder 23 continues to apply pressure. At this time, the wrench sleeve 31 is pre-inserted into the top mold 21, positioned directly above the top bolt of the transducer (or in slight contact with the bolt head); pressure sensor 24 detects the pressing force in real time and feeds it back to the control system. When the pressure value detected by pressure sensor 24 reaches the preset pressing pressure range, the control system switches the solenoid valve to the pressure-holding state, and hydraulic cylinder 23 stops rising and maintains the current pressure. During this process, if the middle template 27 rises beyond the safety limit position, the limit switch 29 installed on the top plate 26 will be triggered by the upper limit switch contact plate 272, and the control system will immediately stop the hydraulic cylinder 23 from rising, thus achieving overtravel protection.

[0083] After the pressure-holding state is established, the control system initiates the servo tightening program. The servo motor 32 first rotates at a low speed, causing the wrench sleeve 31 to rotate slowly one revolution. Due to the axial floating capability between the wrench sleeve 31 and the connecting sleeve 38, the wrench sleeve 31 automatically aligns with the bolt head on the top of the transducer during rotation, ensuring smooth insertion even with slight bolt position deviations. Subsequently, the servo motor 32 accelerates its rotation (the rotation speed can be set on the touchscreen according to process requirements), tightening the bolt at a higher speed. The dynamic torque sensor 33 detects the tightening torque in real time and transmits the data to the control system. When the torque value approaches the upper limit of the preset tightening torque range, the control system reduces the rotation speed of the servo motor 32, making the tightening action a slow tightening motion. Simultaneously, a dedicated transducer testing instrument collects the transducer's electrical performance parameters (such as resonant frequency, dynamic impedance, phase angle, etc.) in real time and sends them to the control system. The control system continuously compares the current transducer performance parameters with the preset target range. Once the transducer's performance parameters reach the set range, the control system immediately sends a stop command to the servo motor 32, and the servo motor 32 stops rotating instantly, completing the tightening process.

[0084] After tightening, the control system switches the solenoid valve to the descent circuit, the output end of the hydraulic cylinder 23 retracts, and the middle mold plate 27 descends. The bottom mold 22 descends with the middle mold plate 27 and separates from the top mold 21. The operator disconnects the detection connection line on the transducer and removes the assembled transducer from the bottom mold 22.

[0085] This completes one assembly cycle. The operator can then place the next transducer and repeat the above steps. The control system automatically records and stores the pressing pressure value, peak tightening torque, and final performance parameters of the transducer during each assembly process, facilitating subsequent product quality traceability and process analysis.

[0086] In summary, by employing a two-step process of "hydraulic pressing followed by servo tightening," a constant pre-pressure is applied to the transducer components via hydraulic cylinder 23 before tightening the bolts, ensuring that the components are fastened without relative displacement. Compared to existing technologies that rely solely on bolt tightening to apply pressure, this effectively avoids transducer performance instability caused by slight relative displacement between components during bolt tightening, significantly improving the consistency and yield of finished transducer products.

[0087] By cooperating with pressure sensor 24 and hydraulic cylinder 23, closed-loop control of the pressing pressure is achieved, ensuring accurate and consistent pressing pressure each time. By cooperating with dynamic torque sensor 33 and servo motor 32, closed-loop control of the tightening torque is achieved, preventing excessive or insufficient torque. By collecting the transducer's own performance parameters in real time as shutdown conditions, precise control guided by the final product quality is achieved. The triple closed-loop control together ensures the assembly quality of each transducer.

[0088] The top mold 21 can be quickly disassembled and assembled without tools via the L-shaped rail 261, and the bottom mold 22 can be easily replaced. The height of the servo tightening assembly can be steplessly adjusted via the handwheel 393 and the trapezoidal lead screw 391. The pressing pressure, tightening torque, and performance parameter thresholds can all be set separately on the touch screen. These designs enable the same tooling to quickly adapt to the production of transducers of different specifications and with different process requirements, making it particularly suitable for multi-variety, small-batch production modes.

[0089] The control system automatically records the pressing pressure, tightening torque, and final performance parameters of the transducer for each assembly, forming a complete production process database. When quality problems occur, they can be traced back to the specific workstation, time, and process parameters, facilitating the analysis of the cause and the implementation of corrective measures, thus meeting the quality traceability requirements of modern manufacturing.

[0090] The machine has a reasonable layout, allowing operators to complete operations such as loading, parameter setting, starting, and unloading without significant movement. The touchscreen interface is intuitive, and parameter setting is simple. The instrument platform 28 places the testing instrument nearby, eliminating the need for additional supports. The cable support plate keeps cables neat and organized, facilitating maintenance. The hydraulic pump 13 is located inside the upper platform, reducing vibration and noise from the worktable.

[0091] The lower frame 11 adopts a stepped double-layer platform structure with strong load-bearing capacity. The hydraulic pressing mechanism 2 uses four guide columns 252 in conjunction with linear bearings, ensuring smooth movement of the middle template 27 without eccentric loading. The connecting plate 351 and reinforcing rib plate 352 of the servo tightening mechanism 3 form an integral frame with high torsional rigidity. The mechanical structure of the tooling is interlocked, making it resistant to loosening and deformation over long-term use, thus ensuring the long-term stability of the equipment's service life and assembly accuracy.

[0092] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An automatic pressing and tightening fixture for transducers, characterized in that, include: Rack assembly (1); The hydraulic pressing mechanism (2) is provided on the frame assembly (1). The hydraulic pressing mechanism (2) includes a top mold (21) and a bottom mold (22) arranged opposite to each other, a hydraulic cylinder (23) for driving the bottom mold (22) to move toward the top mold (21), and a pressure sensor (24) for detecting the pressing pressure. The servo tightening mechanism (3) is located above the hydraulic pressing mechanism (2). The servo tightening mechanism (3) includes a wrench sleeve (31) for tightening bolts, a servo motor (32) for driving the wrench sleeve (31) to rotate, and a dynamic torque sensor (33) for detecting tightening torque.

2. The transducer automatic pressing and tightening fixture according to claim 1, characterized in that: The frame assembly (1) includes a lower frame (11), which is a stepped combination of a lower platform and an upper platform; the hydraulic pressing mechanism (2) and the servo tightening mechanism (3) constitute a pressing and tightening component and are set on the lower platform; a touch screen assembly (12) is also set on the lower platform; a hydraulic pump (13) is set inside the upper platform.

3. The transducer automatic pressing and tightening fixture according to claim 1, characterized in that: The hydraulic pressing mechanism (2) further includes a platform (25) fixed on the frame assembly (1), a base plate (251) fixed above the platform (25), a plurality of guide columns (252) vertically arranged on the base plate (251), a top plate (26) fixed to the top of each guide column (252), and a middle template (27) slidably sleeved on each guide column (252) via a linear bearing. The top mold (21) is detachably installed at the bottom of the top plate (26), and the bottom mold (22) is installed at the top of the middle mold plate (27); the hydraulic cylinder (23) is installed at the bottom of the platform (25), and the output end of the hydraulic cylinder (23) passes through the platform (25) and is connected to the bottom of the middle mold plate (27) through the pressure sensor (24); an instrument storage platform (28) is provided on the top of the platform (25).

4. The transducer automatic pressing and tightening fixture according to claim 3, characterized in that: The hydraulic pressing mechanism (2) also includes a contact plate mounting rod (271) disposed on one side of the middle template (27), and two limit switch contact plates (272) respectively located above and below the middle template (27) are disposed on the contact plate mounting rod (271); a limit switch (29) is disposed on one side of the bottom plate (251) and the top plate (26); when the middle template (27) rises or falls to the limit position, the corresponding limit switch contact plate (272) triggers the limit switch (29).

5. The transducer automatic pressing and tightening fixture according to claim 1, characterized in that: The servo tightening mechanism (3) further includes a guide shaft connecting plate (34), a plurality of guide shafts (341) vertically arranged at the bottom of the guide shaft connecting plate (34), a reducer mounting plate (35) slidably sleeved on each of the guide shafts (341) via linear bearings, and a support mounting plate (36) slidably sleeved on each of the guide shafts (341) via linear bearings. The top of the support mounting plate (36) is provided with a support base (361); the servo motor (32) is mounted on the reducer mounting plate (35) through the reducer (321); the two ends of the dynamic torque sensor (33) are respectively connected to the output end of the reducer (321) and a tightening spindle (37) through the first coupling (331) and the second coupling (332); the tightening spindle (37) is rotatably supported inside the support base (361) and its bottom end is connected to the wrench sleeve (31); the guide shaft connecting plate (34) is provided with a clearance hole (342).

6. The transducer automatic pressing and tightening fixture according to claim 1, characterized in that: The servo tightening mechanism (3) further includes two connecting plates (351) fixedly connected between the reducer mounting plate (35) and the support mounting plate (36). The two connecting plates (351) are arranged opposite to each other, and a reinforcing rib (352) and a sensor mounting plate (353) for mounting the dynamic torque sensor (33) are respectively provided between the two connecting plates (351).

7. The transducer automatic pressing and tightening fixture according to claim 1, characterized in that: The bottom end of the tightening spindle (37) and the top end of the wrench sleeve (31) are both provided with square structures. The interior of the connecting sleeve (38) is provided with square holes that mate with the square structures. The circumferential torque is transmitted between the tightening spindle (37) and the connecting sleeve (38), and between the connecting sleeve (38) and the wrench sleeve (31), through the mating of the square structures and the square holes. The top end of the connecting sleeve (38) is axially limited to the tightening spindle (37) by a first pin (381). The top end of the wrench sleeve (31) is inserted into the connecting sleeve (38) and has a waist-shaped hole (311). The connecting sleeve (38) and the wrench sleeve (31) are connected by a second pin (382) passing through the waist-shaped hole (311). The second pin (382) cooperates with the waist-shaped hole (311) to allow the wrench sleeve (31) to float axially relative to the connecting sleeve (38). At the same time, the second pin (382) plays an axial limiting role for the wrench sleeve (31).

8. The transducer automatic pressing and tightening fixture according to claim 5, characterized in that: The servo tightening mechanism (3) further includes a lifting adjustment component (39) for adjusting the working height of the servo motor (32). The lifting adjustment component (39) includes a trapezoidal lead screw (391) rotatably mounted on the guide shaft connecting plate (34), a lead screw nut (392) fixed on the reducer mounting plate (35), and a handwheel (393) mounted on the top of the trapezoidal lead screw (391). The trapezoidal lead screw (391) and the lead screw nut (392) are connected in cooperation.

9. The transducer automatic pressing and tightening fixture according to claim 4, characterized in that: A quick-release structure is provided between the top plate (26) and the top mold (21). The quick-release structure includes two L-shaped rails (261) symmetrically fixed to the bottom of the top plate (26). A T-shaped installation space is formed between the two L-shaped rails (261), and the top mold (21) is slidably engaged in the T-shaped installation space.

10. The automatic pressing and tightening fixture for a transducer according to claim 1, characterized in that: The servo tightening mechanism (3) also includes a U-shaped photoelectric switch (362) set at the bottom of the support mounting plate (36) and a sensing plate (371) fixed on the tightening spindle (37). The U-shaped photoelectric switch (362) and the sensing plate (371) are used to position the servo motor (32) back to the origin.

Images