A fully automatic bone lengthening and shortening device based on permanent magnet drive

Abstract

The present invention discloses a fully automatic bone lengthening and shortening device based on permanent magnet drive. It comprises: a support module including a linear guide rail and a plurality of sliding clamps arranged on the linear guide rail, the sliding clamps being used to install fixing nails; a telescopic module being installed on the sliding clamp to be fixed, comprising a power and telescopic unit, the power unit driving the telescopic end of the telescopic unit to extend and retract through the rotation of the rotor magnet, and the telescopic end of the telescopic unit being able to drive the sliding clamp to be movable to move; a driving module and the telescopic module being installed on the same sliding clamp, comprising two permanent magnets located above the rotor magnet, the driving module driving the rotor magnet to rotate through the magnetic field generated by the permanent magnet. The present invention can realize intelligent control of bone lengthening and shortening through the movable connection between the support module and the telescopic module, in cooperation with an external driving module, achieving high positioning accuracy and high traction frequency, while having the functions of real-time feedback of lengthening and shortening, and real-time adjustment of lengthening and shortening requirements.

Description

Technical Field

[0001] The present invention relates to the technical field of bone lengthening and shortening, and in particular to a full-automatic bone lengthening and shortening device based on permanent magnet drive. Background Art

[0002] Bone transport technology is a medical technique that uses mechanical means to gradually stretch bones. It is commonly used to treat various bone and soft tissue diseases caused by trauma, tumors, or other causes. In the 1950s, Russian physician Gavriil Ilizarov proposed distraction osteogenesis, based on the tension-stress principle. By gradually stretching the bone using external force, it promotes new bone formation, achieving the goal of bone and soft tissue generation and repair. It has now become the gold standard for procedures such as limb orthopedics, bone and soft tissue repair, and diabetic foot treatment. Currently, bone transport fixation methods mainly include external fixators, external fixators combined with intramedullary nails, internal and external extension systems combined with steel plates, and intramedullary nail extension systems.

[0003] External fixators used in bone transport surgery can be divided into circular external fixators, unilateral external fixators, etc. according to their structures. Among them, unilateral external fixators have been widely used in clinical practice due to their advantages such as compact structure, simple operation, and strong adaptability, and are of great significance for orthopedic treatment.

[0004] In clinical treatment, external fixation devices usually require patients to manually adjust bone transport, which poses many problems:

[0005] 1. Frequent manual operations are prone to errors and inadequate operation, which increase the probability of postoperative complications and lead to the risk of various secondary surgeries;

[0006] 2. It places certain demands on the patients themselves, such as requiring them to perform the operation on time, master the steps and accuracy of the operation, and overcome psychological barriers to self-operation. In clinical practice, various accidents may occur due to the patients' mental stress;

[0007] 3. Manual operation makes it difficult to grasp the real-time effect of bone lengthening and cannot ensure the accuracy of lengthening. Patients need to frequently visit the hospital for readjustment through X-rays and CT scans, which increases the burden on patients.

[0008] 4. Existing external fixators usually operate at a low traction frequency of 3 to 4 times a day at a traction speed of 0.75 to 1 mm / day. Not only is the bone regeneration and repair effect not optimal, but the long treatment cycle seriously affects the patient's quality of life. Summary of the Invention

[0009] This invention addresses the challenges of existing external fixation devices, such as complex operation, poor positioning accuracy, long treatment cycles, and low intelligence. By providing a fully automatic bone lengthening and shortening device based on permanent magnet drive, this device features simple assembly of the telescopic and support modules, and automated operation of the drive module, ensuring ease of operation and reducing patient intervention requirements. The detailed operation of the telescopic module and the effective coordination of the drive module ensure high positioning accuracy. Optimizing the drive module's operation helps shorten the bone transport treatment cycle.

[0010] The technical solution adopted in the present invention is:

[0011] 1. A fully automatic bone lengthening and shortening device based on permanent magnet drive

[0012] The fully automatic bone lengthening and shortening device comprises:

[0013] A support module includes a linear guide rail and a plurality of sliding fixtures arranged on the linear guide rail, wherein the sliding fixtures are used to install fixing nails;

[0014] The telescopic module is mounted on the sliding fixture to be fixed, and includes a power unit and a telescopic unit. The power unit includes a rotor magnet. The rotation of the rotor magnet drives the telescopic end of the telescopic unit to extend and retract, thereby driving the sliding fixture to be movable to move along the length direction of the linear guide rail.

[0015] The driving module is mounted on the same sliding fixture as the telescopic module and includes two permanent magnets located above the rotor magnet. The driving module drives the rotor magnet to rotate through the magnetic field generated by the permanent magnets.

[0016] The rotor magnet and the two permanent magnets are both cylindrical magnets, and the magnetization direction is radial; the axes of the two permanent magnets and the rotor magnet are parallel to each other, and the two permanent magnets are symmetrically arranged on both sides above the rotor magnet, and the rotation speed and direction of the two permanent magnets are consistent.

[0017] Among them, "two permanent magnets are symmetrically arranged on both sides above the rotor magnet" specifically means that the axes of the three form three projection points on the radial plane, and the three projection points are connected to form a triangle, preferably an isosceles triangle with the axis projection point of the rotor magnet as the vertex.

[0018] The telescopic module also includes a shell and an anti-rotation lug; a power unit and a telescopic unit are installed in the shell, and the anti-rotation lug is installed at one end of the shell, that is, the end where the telescopic unit is located. The anti-rotation lug is used to limit the rotation of the telescopic end of the telescopic unit, that is, the extension rod, and provide a guiding function for the extension rod.

[0019] The power unit also includes a rotor magnet sleeve, an input end gear, a reducer and a connecting piece; the rotor magnet sleeve is arranged on the outside of the rotor magnet, one end of the rotor magnet sleeve is connected to the reducer through the input end gear, and the input end gear is the sun gear of the first stage transmission. One end of the connecting piece is integrated with an eccentric shaft and is connected to the planetary carrier output end of the reducer through the eccentric shaft, and the other end of the connecting piece is connected to the telescopic unit.

[0020] The telescopic unit includes a threaded rod, a sealing ring, a threaded sleeve and an extension rod; the threaded rod is connected to the connecting piece, the radial outer side of the threaded rod is sleeved with a threaded sleeve, one end of the extension rod is sleeved on the outer side of the threaded sleeve, and the radial outer side of the end is embedded with a sealing ring, the other end of the extension rod extends from the outer shell, the extension rod is provided with a groove adapted to the anti-rotation lug, and the sealing ring is slidably and sealedly matched with the outer shell.

[0021] Preferably, the reducer is fixed by interference fit with the housing, and the connecting piece is fixed by interference fit with the housing through the first bearing assembly.

[0022] The fully automatic bone lengthening and shortening device also includes a first fixed foot, a second fixed foot, a third fixed foot, a first drive connector and a second drive connector; the top of the second fixed foot is detachably fixedly connected to the outer shell of the telescopic module, and the top of the third fixed foot is equipped with a third bearing assembly that cooperates with each other, and the end of the rotor magnet sleeve away from the reducer cooperates with the third bearing assembly; a guide groove is opened on one side of the top of the first fixed foot, and the extension rod is inserted into the guide groove after extending from the outer shell.

[0023] There are fixed foot mounting holes on both sides of each sliding clamp, and the fixed foot mounting holes are opened in the vertical direction; the first fixed foot is inserted into the fixed foot mounting hole on the sliding clamp to be movable, preferably the fixed foot mounting hole on the side away from the power unit; the second fixed foot and the third fixed foot are respectively inserted into the two fixed foot mounting holes of the same sliding clamp to be fixed.

[0024] The upper and lower ends of the first drive connector and the second drive connector are respectively connected to the drive module and the sliding clamp; the first drive connector and the second drive connector both include a base plate that is adapted to the shape of both sides of the sliding clamp base of the sliding clamp, and a through hole is opened on the base plate, and the through hole is aligned with the fixed leg mounting hole up and down, and the base plate is detachably fixed to the sliding clamp base of the sliding clamp; the second fixed leg and the third fixed leg pass through the through hole above their respective corresponding fixed leg mounting holes, and then are inserted into the fixed leg mounting holes.

[0025] The driving module also includes a display screen, a control unit, a reduction stepper motor, a transmission gear and a three-jaw chuck; the display screen is used as an interactive interface to receive control instructions and send them to the control unit, the display screen is electrically connected to the control unit, and the control unit is electrically connected to the reduction stepper motor and controls the reduction stepper motor; the output shaft of the reduction stepper motor is connected to the gear shaft of the driving wheel in the transmission gear, and the gear shafts of the two output driven wheels in the transmission gear are each connected to a three-jaw chuck, and each of the two three-jaw chucks is installed with a permanent magnet.

[0026] The driving module also includes a driving module housing, a left fixed plate, a right fixed plate, a magnet protective cover, a locking nut and a bolt; the left fixed plate and the right fixed plate are arranged opposite to each other on both sides of the transmission gear, a reduction stepping motor is installed on the side of the left fixed plate away from the right fixed plate, and a three-jaw chuck, a permanent magnet and a magnet protective cover are arranged on the side of the right fixed plate away from the left fixed plate; the left fixed plate and the right fixed plate are limitedly connected by a locking nut and a bolt, and the gear shaft of each driven wheel in the transmission gear is installed on the left fixed plate and the right fixed plate through a second bearing assembly, and the magnet protective cover is sleeved on the outside of the two permanent magnets and fixedly connected to the right fixed plate.

[0027] The control unit controls the deceleration stepping motor according to the settings of the pulling and shortening frequency being 1 to 120 times per day and the pulling length being 1.0 to 2.0 mm per day.

[0028] The sliding clamp includes a sliding clamp base, a sliding clamp upper cover, a flat washer and a screw; the screw is installed at the bottom of the linear guide rail, and the sliding clamp base is lockably connected to the linear guide rail through the screw; a flat washer is provided between the screw and the linear guide rail; the sliding clamp upper cover is lockably installed on the top of the sliding clamp base; the sliding clamp base and the sliding clamp upper cover are enclosed to form a plurality of holes, and the holes are used to accommodate fixing nails; fixing foot mounting holes are vertically opened on both sides of the sliding clamp base.

[0029] The telescopic module further includes a displacement sensor for collecting the displacement of the telescopic end of the telescopic unit. The displacement sensor is communicatively connected to the control unit of the driving module.

[0030] 2. An assembly method for a fully automatic bone lengthening and shortening device

[0031] The assembly method comprises the following steps:

[0032] S1. Connect the sliding fixture and the fixing pin, and lock the sliding fixture to be fixed;

[0033] S2. Place the first driver connector and the second driver connector on the fixed leg mounting holes on both sides of the sliding fixture to be fixed, aligning the through-holes with the fixed leg mounting holes. Assemble the telescopic module, the second fixed leg, and the third fixed leg. Then, insert the second and third fixed legs through their corresponding through-holes and then into the fixed leg mounting holes below the through-holes. Insert the first fixed leg into the fixed leg mounting hole of the sliding fixture to be moved.

[0034] S3, detachably and fixedly connecting the driving module to the first driver connector and the second driver connector respectively;

[0035] S4. Pre-starting the drive module, using the magnetic field generated by the permanent magnet in the drive module to drive the rotor magnet to rotate, thereby causing the end of the extension rod to extend into the guide groove of the first fixed leg, with the end face contacting the inner wall of the bottom of the guide groove;

[0036] S5. Input control instructions through the display screen, control the driving module according to the control instructions, and further control the extension and shortening distance and frequency of the extension rod.

[0037] The beneficial effects of the present invention are:

[0038] 1. The device of the present invention adopts permanent magnet drive, which can provide a stronger driving magnetic field and overcome the problem of long-term heating of traditional electromagnetic coils, thus extending the service life.

[0039] 2. The device of the present invention can achieve extension and shortening by only operating and controlling the permanent magnetic drive, which is simple to operate and ensures extension accuracy while simplifying the operation.

[0040] 3. The device of the present invention adopts a fully automatic working mode. By realizing high-frequency continuous extension or shortening operations, it can restore the natural growth process of bones in a targeted manner, ensure the bone healing effect while reducing the patient's pain, and provide better accuracy.

[0041] 4. The device of the present invention mostly adopts an interference fit connection method to ensure the strength of the structure; and by directly connecting the driving module and the telescopic module, it ensures the stable provision of the magnetic field, avoids frequent disassembly and correction, and enables the patient to move more freely.

[0042] In summary, the present invention, through the flexible connection between the support module and the telescopic module, in conjunction with an external drive module, enables intelligent control of bone lengthening and shortening, achieving high positioning accuracy and high traction frequency. It also provides real-time feedback on length extension and shortening, and real-time adjustment of extension and shortening requirements. The device provided by the present invention can provide a maximum length extension or shortening of 100 mm, a maximum daily traction of 2.0 mm, and a traction frequency of up to 120 times per day. This device better aligns with the physiological characteristics of human bone growth, effectively reducing the likelihood of complications, shortening the bone transport treatment cycle, and improving efficacy. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 Schematic diagram of the overall structure of the bone lengthening device of the present invention;

[0044] Figure 2 Schematic diagram of the structure of the support module in the bone lengthening device of the present invention;

[0045] Figure 3 Schematic diagram of the structure of the telescopic module in the bone lengthening device of the present invention;

[0046] Figure 4 Schematic diagram of the expansion of the telescopic module in the bone lengthening device of the present invention;

[0047] Figure 5 Schematic diagram of the internal structure of the third fixed leg in the bone lengthening device of the present invention;

[0048] Figure 6 Schematic diagram of the internal structure of the permanent magnetic driver in the bone lengthening device of the present invention;

[0049] Figure 7 Schematic diagram of the internal control unit of the permanent magnetic drive in the bone lengthening device of the present invention;

[0050] Figure 8 Schematic diagram of the internal structure of the left / right fixation plate in the bone lengthening device of the present invention;

[0051] Figure 9 Schematic diagram of the operation and control flow of the bone lengthening device of the present invention;

[0052] Figure 10 Schematic diagram of the layout of the permanent magnets and rotor magnets in the bone lengthening device of the present invention.

[0053] In the figure: 10-support module, 11-linear guide, 12-fixing nail, 13-sliding fixture base, 14-sliding fixture cover, 15-flat washer, 16-screw, 20-telescopic module, 21-housing, 22-anti-rotation lug, 23-rotor magnet sleeve, 24-rotor magnet, 25-input end gear, 26-reducer, 27-bearing fixing part, 28-thrust bearing, 29-connecting part, 210-threaded rod, 211-sealing ring, 212-threaded sleeve, 213-extension rod, 30-drive module, 31-upper housing, 32-display Display screen, 33-lower housing, 34-reduction stepper motor, 35-motor seat, 36-left fixed plate, 37-transmission gear, 38-right fixed plate, 39-three-jaw chuck, 310-magnet protection cover, 311-permanent magnet, 312-locking nut, 313-bolt, 314-first deep groove ball bearing, 315-first bearing retaining ring, 40-first fixed foot, 50-second fixed foot, 60-third fixed foot, 61-second deep groove ball bearing, 62-second bearing retaining ring, 70-first drive connector, 80-second drive connector. DETAILED DESCRIPTION

[0054] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0055] The proposed permanent magnet-driven, fully automated bone lengthening and shortening device is implemented through the combined efforts of a support module, a telescopic module, and a drive module. The support module, comprised of linear guides, sliding fixtures, and related accessories, offers advantages such as flexible movement and adjustable length, adapting to diverse application scenarios. The telescopic module, comprised of an internal drive unit, a telescopic unit, and a housing, boasts high positioning accuracy and full automation. The drive module, which provides a variable external magnetic field to power the internal drive unit, boasts a high degree of intelligence and generates a strong alternating magnetic field.

[0056] like Figure 1 As shown, the fully automatic bone lengthening and shortening device provided by the present invention includes:

[0057] The support module 10 includes a linear guide rail 11 and a plurality of sliding fixtures arranged on the linear guide rail 11, and the sliding fixtures are used to install fixing pins 12;

[0058] The telescopic module 20 is mounted on the sliding fixture to be fixed and includes a power unit and a telescopic unit. The power unit includes a rotor magnet 24. The rotation of the rotor magnet 24 drives the telescopic end of the telescopic unit to perform telescopic movement, thereby driving the sliding fixture to be moved on the linear guide 11 along the length direction of the linear guide 11.

[0059] The driving module 30 is mounted on the same sliding fixture that needs to be fixed as the telescopic module 20 , and includes two permanent magnets 311 located above the rotor magnet 24 . The driving module 30 drives the rotor magnet 24 to rotate through the magnetic field generated by the permanent magnets 311 .

[0060] Specifically, if Figure 10 As shown, the rotor magnet 24 and the two permanent magnets 311 are both cylindrical magnets, and the magnetization direction is radial; the axes of the two permanent magnets 311 and the rotor magnet 24 are parallel to each other, and the two permanent magnets 311 are symmetrically arranged on both sides above the rotor magnet 24, and the rotation speed and direction of the two permanent magnets 311 are consistent.

[0061] Among them, "two permanent magnets 311 are symmetrically arranged on both sides above the rotor magnet 24" specifically means that: the axes of the three (the two permanent magnets 311 and the rotor magnet 24) form three projection points on the radial plane, and the three projection points are connected to form a triangle, preferably an isosceles triangle with the axis projection point of the rotor magnet 24 as the vertex.

[0062] Specifically, if Figure 2 As shown, the telescopic module 20 also includes a housing 21 and an anti-rotation lug 22. The power unit and the telescopic unit are mounted within the housing 21. The anti-rotation lug 22 is mounted at one end of the housing 21, where the telescopic unit resides. The anti-rotation lug 22 is used to limit the rotation of the telescopic end of the telescopic unit, i.e., the extension rod 213, and to provide guidance for the extension rod 213.

[0063] Specifically, if Figure 3 and Figure 4 As shown, the power unit also includes a rotor magnet sleeve 23, an input end gear 25, a reducer 26 and a connector 29. The reducer 26 is preferably a planetary reducer. The rotor magnet sleeve 23 is sleeved on the radially outer side of the rotor magnet 24. One end of the rotor magnet sleeve 23 is connected to the reducer 26 through the input end gear 25. The input end gear 25 is the sun gear of the first stage transmission. One end of the connector 29 is integrally provided with an eccentric shaft and is connected to the planetary carrier output end of the reducer 26 through the eccentric shaft. The other end of the connector 29 is connected to the telescopic unit.

[0064] Preferably, the reducer 26 is fixed by interference fit with the housing 21 , and the connector 29 is fixed by interference fit with the housing 21 through the first bearing assembly.

[0065] like Figure 4As shown, in the above preferred embodiment, "connecting member 29 is fixed by an interference fit between the first bearing assembly and the housing 21" specifically means that the first bearing assembly includes a bearing fixing member 27 and a thrust bearing 28. The thrust bearing 28 is disposed radially outwardly of the connecting member 29 and engages with the connecting member 29. The bearing fixing member 27 is disposed radially outwardly of the thrust bearing 28 and engages with the thrust bearing 28. The bearing fixing member 27 has an interference fit with the housing 21.

[0066] Furthermore, the reducer 26 may also be a planetary reducer, a harmonic reducer or an RV reducer.

[0067] Specifically, if Figure 4 As shown, the telescopic unit includes a threaded rod 210, a sealing ring 211, a threaded sleeve 212 and an extension rod 213; the threaded rod 210 is connected to the connecting piece 29, and the threaded sleeve 212 is sleeved on the radial outer side of the threaded rod 210. One end of the extension rod 213 is sleeved on the outer side of the threaded sleeve 212, and the sealing ring 211 is embedded in the radial outer side of the end. The other end of the extension rod 213 extends from the outer shell 21 to form a telescopic end. A groove adapted to the anti-rotation lug 22 is provided on the outer peripheral surface of the extension rod 213, and the sealing ring 211 is slidably and sealedly matched with the outer shell 21.

[0068] Further, if Figure 1 As shown, the fully automatic bone lengthening device further comprises a first fixing foot 40, a second fixing foot 50 and a third fixing foot 60. The top of the second fixing foot 50 is detachably fixedly connected to the housing 21 of the telescopic module 20. Figure 5 As shown, a third bearing assembly is installed on the top of the third fixed foot 60, and the third bearing assembly is mainly composed of a second deep groove ball bearing 61 and a second bearing retaining ring 62 that cooperate with each other. The end of the rotor magnet sleeve 23 away from the reducer 26 extends into the second deep groove ball bearing 61 and cooperates with the second deep groove ball bearing 61; a guide groove is provided on one side of the top of the first fixed foot 40, and the end of the extension rod 213 away from the reducer 26 extends from the housing 21 and is inserted into the guide groove.

[0069] Specifically, the guide groove is a blind groove.

[0070] Further, if Figure 2 As shown, each sliding fixture has mounting holes for fixed legs on both sides, preferably along the length of the linear guide rail 11. These holes are vertically oriented for mounting the fixed legs (first, second, and third fixed legs 40, 50, and 60). The first fixed leg 40 is inserted into a mounting hole on the movable sliding fixture, preferably on the side away from the power unit. The second and third fixed legs 50, 60 are inserted into two mounting holes on the same fixed fixture.

[0071] Furthermore, if Figure 1 As shown, the fully automatic bone lengthening device also includes a first driver connector 70 and a second driver connector 80. The first and second driver connectors 70 and 80 are arranged between the sliding fixture and the driving module 30, with their upper and lower ends connected to the driving module 30 and the sliding fixture, respectively. The first and second driver connectors 70 and 80 each include a base plate that matches the shape of the sliding fixture base 13 on both sides of the sliding fixture. The base plate has through-holes that are aligned vertically with the corresponding fixing leg mounting holes. The base plate is detachably fixed to the sliding fixture base 13 of the sliding fixture. The second and third fixing legs 50 and 60 pass through their respective through-holes and are then inserted into the fixing leg mounting holes below the through-holes.

[0072] Furthermore, if Figure 6 and Figure 7 As shown, the driving module 30 also includes a display screen 32, a control unit, a deceleration stepper motor 34, a transmission gear 37 and a three-jaw chuck 39; the display screen 32 is used as a user interaction interface, the display screen 32 is electrically connected to the control unit, the control unit is electrically connected to the deceleration stepper motor 34 and controls the deceleration stepper motor 34; the output shaft of the deceleration stepper motor 34 is connected to the gear shaft of the driving wheel in the transmission gear 37, and the gear shafts of the two output driven wheels in the transmission gear 37 are each connected to a three-jaw chuck 39, and each of the two three-jaw chucks 39 is mounted with a permanent magnet 311.

[0073] Furthermore, if Figure 6 As shown, the drive module 30 also includes a drive module housing, a left fixed plate 36, a right fixed plate 38, a magnet protection cover 310, a locking nut 312 and a bolt 313; the left fixed plate 36 and the right fixed plate 38 are arranged at opposite intervals on both sides of the transmission gear 37, and the outer side of the left fixed plate 36 (i.e., the side away from the right fixed plate 38) is installed with a reduction stepping motor 34, and the outer side of the right fixed plate 38 (i.e., the side away from the left fixed plate 36) is arranged with a three-jaw chuck 39, a permanent magnet 311 and a magnet protection cover 310; the left fixed plate 36 and the right fixed plate 38 are fixedly connected by a locking nut 312 and a bolt 313, and the gear shaft of each driven wheel in the transmission gear 37 is mounted on the left fixed plate 36 and the right fixed plate 38 through a second bearing assembly, and the magnet protection cover 310 is sleeved on the outer sides of the two permanent magnets 311 and fixedly connected to the side of the right fixed plate 38.

[0074] Preferably, the driving module housing is mainly composed of an upper housing 31 and a lower housing 33. The upper housing 31 and the lower housing 33 are arranged one above the other and are bonded together.

[0075] It should be noted that the transmission gear 37 may include multiple driven wheels, only two of which are directly connected to the load (three-jaw chuck 39 and permanent magnet 311) and transmit power, while the remaining driven wheels only perform power distribution or steering functions. In the present invention, the two driven wheels connected to the permanent magnet 311 are collectively referred to as output driven wheels. For example, in this embodiment of the present invention, the transmission gear 37 includes four driven wheels, with the two bottom-most driven wheels serving as output driven wheels, respectively connected to the two three-jaw chucks 39.

[0076] Specifically, if Figure 8 As shown, the second bearing assembly includes a first deep groove ball bearing 314 and a first bearing retaining ring 315 .

[0077] Furthermore, the control unit controls the deceleration stepping motor 34 according to the setting of the pulling and shortening frequency being 1 to 120 times / day and the pulling length being 1 to 2.0 mm / day.

[0078] Specifically, if Figure 2 As shown, the sliding fixture includes a sliding fixture base 13, a sliding fixture cover 14, a flat washer 15 and a screw 16. The screw 16 is installed at the bottom of the linear guide 11, and the sliding fixture base 13 is lockably connected to the linear guide 11 through the screw 16. A flat washer 15 is provided between the screw 16 and the linear guide 11, and the flat washer 15 is sleeved on the outside of the screw 16 to cushion and prevent the screw 16 from loosening. By tightening the screw 16, the tip of the screw 16 is pressed against the bottom surface of the sliding fixture base 13, thereby fixing the sliding fixture base 13 on the linear guide 11; by loosening the screw 16, the tip of the screw 16 is no longer pressed against the bottom surface of the sliding fixture base 13, thereby enabling the sliding fixture base 13 to move back and forth on the linear guide 11. A sliding clamp cover 14 is lockably mounted on the top of the sliding clamp base 13 ; the sliding clamp base 13 and the sliding clamp cover 14 enclose a plurality of holes for accommodating the fixing pins 12 ; fixing foot mounting holes are vertically opened on both sides of the sliding clamp base 13 .

[0079] Specifically, the sliding fixture base 13 is movably connected to the linear guide rail 11 in a lockable manner. That is, the sliding fixture can reciprocate on the linear guide rail 11 along the length direction of the linear guide rail 11. When fixed, the movement of the sliding fixture base 13 can be restricted by locking.

[0080] Optionally, the sliding fixture base 13 is in rolling contact or sliding contact with the linear guide rail 11, thereby achieving a movable connection.

[0081] Preferably, the hole position can be adapted to a fixing nail 12 with a diameter of 4 to 8 mm.

[0082] Furthermore, the telescopic module 20 also includes a displacement sensor for collecting the displacement of the telescopic end of the telescopic unit. The displacement sensor is in communication with the control unit of the drive module 30. The displacement sensor feeds the collected displacement information back to the control unit of the drive module 30, thereby achieving closed-loop control.

[0083] In a specific implementation, the number of the sliding clamps may be two, one is a sliding clamp that needs to be moved, and the other is a sliding clamp that needs to be kept fixed.

[0084] In a specific implementation, the number of sliding clamps can be three. The sliding clamps located at both ends of the linear guide rail 11 need to remain fixed, and the sliding clamp located in the middle needs to move; the telescopic module 20 and the driving module 30 are installed on the sliding clamp at the same end.

[0085] The device of the present invention is suitable for a variety of medical application scenarios that require lengthening and shortening operations, including but not limited to diseases such as limb length inequality, skeletal deformities, bone and soft tissue defects caused by various reasons.

[0086] The assembly method of the fully automatic bone lengthening and shortening device of the present invention comprises the following steps:

[0087] S1. Connect the sliding fixture and the fixing pin 12, and lock the sliding fixture to be fixed on the linear guide rail 11;

[0088] S2. Place the first driver connector 70 and the second driver connector 80 on the two fixed leg mounting holes of one of the sliding fixtures to be fixed, aligning the through-holes with the fixed leg mounting holes. Assemble the telescopic module 20, the second fixed leg 50, and the third fixed leg 60. Then, insert the second fixed leg 50 and the third fixed leg 60 through their corresponding through-holes and then into the fixed leg mounting holes below the through-holes. Insert the first fixed leg 40 into the fixed leg mounting hole of the sliding fixture to be moved.

[0089] S3, detachably and fixedly connecting the driving module 30 to the first driving connector 70 and the second driving connector 80 respectively;

[0090] S4. Pre-start the drive module 30 and use the magnetic field generated by the permanent magnet 311 in the drive module 30 to drive the rotor magnet 24 to rotate, thereby causing the end of the extension rod 213 to extend into the guide groove of the first fixed leg 40, with the end face contacting the inner wall of the bottom of the guide groove;

[0091] S5. Input a control instruction through the display screen 32, control the driving module 30 according to the control instruction, and further control the extension and shortening distance and frequency of the extension rod 213.

[0092] The specific embodiments of the present invention are as follows:

[0093] First, taking the installation process of the lengthening operation as an example, the assembly, movement and main functions of the various components of the bone lengthening and shortening device provided in this embodiment are explained.

[0094] ①Support module 10:

[0095] like Figure 2 As shown, three sliding fixtures are provided on the linear guide rail 11, which are the first sliding fixture, the second sliding fixture, and the third sliding fixture from left to right. For each sliding fixture, the contact mode between the sliding fixture base 13 and the linear guide rail 11 is sliding friction.

[0096] During use, the first and third sliding fixtures' sliding fixture bases 13 can be secured to the linear guide rail 11 as needed. This is achieved by tightening the screws 16 below the linear guide rail 11, with the flat washers 15 providing cushioning and anti-loosening properties. The second sliding fixture's sliding fixture base 13 is a movable component, allowing it to move freely along the linear guide rail 11 depending on bone elongation.

[0097] Insert the fixed pin 12, which is inserted into the body, through the hole between the sliding clamp base 13 and the sliding clamp cover 14. Then, tighten it with the screw above the sliding clamp cover 14 to secure it, thereby connecting the sliding clamp to the fixed pin 12. The pinhole can accommodate fixed pins 12 with a diameter of 4-8mm. It should be noted that the fixed pin 12 should remain in the same plane after being inserted. If there is a slight angle between the two planes, adjust the position of the sliding clamp cover 14 before securing it.

[0098] ② Telescopic module 20:

[0099] After the support module 10 is installed, the drive module 30 is required to move the telescopic end of the telescopic module 20 to an appropriate length for subsequent operations.

[0100] like Figure 2 As shown, the large-diameter end (left end) of the telescopic module 20 contacts the third fixed leg 60. The small-diameter end (left end) of the rotor magnet sleeve 23 should pass through the second deep-groove ball bearing 61 within the third fixed leg 60 to ensure smooth rotation. The second deep-groove ball bearing 61 is secured on one side by the shoulder of the third fixed leg 60 and on the other side by a second bearing retaining ring 62 embedded in the third fixed leg 60. The small-diameter end (right end) of the telescopic module 20 contacts the first fixed leg 40. The end of the telescopic end of the telescopic module 20 extends into the guide groove (not through-hole) on the first fixed leg 40. No constraints are required here because during bone lengthening, the pressure exerted by the muscles on the support module 10 through the fixing pins 12 is sufficient to ensure a tight fit between the two.

[0101] In this embodiment, the first fixing leg 40 is positioned on the right side of the second sliding fixture, the second fixing leg 50 is positioned on the right side of the first sliding fixture, and the third fixing leg 60 is positioned on the left side of the first sliding fixture. During installation, first insert the outer shell 21 of the telescopic module 20 through the inner hole at the top of the second fixing leg 50. Adjust the second fixing leg 50 to the appropriate position, ensuring that the first fixing leg 40, the second fixing leg 50, and the third fixing leg 60 can all pass through the corresponding fixing leg mounting holes on the sliding fixture base 13 where they are located. A threaded nut should also be used to secure the top structure of the second fixing leg 50 to the outer shell 21 of the telescopic module 20 to prevent the outer shell 21 from rotating.

[0102] The internal structure of the telescopic module 20 is as follows Figure 4 As shown, the telescopic module 20 can be further divided into the left power unit, which mainly includes the rotor magnet sleeve 23, rotor magnet 24, input end gear 25, reducer 26, bearing fixture 27, thrust bearing 28, and connector 29; and the right telescopic unit, which mainly includes a threaded rod 210, a sealing ring 211, a threaded sleeve 212, and an extension rod 213. The reducer 26 is a planetary reducer. The rotor magnet 24 is fixedly connected to the rotor magnet sleeve 23 with an adhesive. The left side of the rotor magnet sleeve 23 is fixed and supported by the second deep groove ball bearing 61 inside the external third fixing foot 60. The right side can be directly inserted into the reducer 26 for connection via the input end gear 25. The outer side of the connector 29 is sequentially mounted with a thrust bearing 28 and a bearing fixture 27. After the thrust bearing 28 and the connector 29 are positioned and connected via a shaft shoulder, the bearing fixture 27 is fixed to the thrust bearing 28 from the right side. The left end of the connector 29 is connected to the planetary carrier output of the reducer 26 via an eccentric shaft. The right end of connector 29 is connected to the left end of threaded rod 210 via a cylindrical pin. Reducer 26 and bearing fixture 27 are both secured via an interference fit with housing 21. Threaded rod 210 is connected to the left end of extension rod 213 via threaded sleeve 212, which primarily protects the threads of extension rod 213. A sealing ring 211 fits into the external stepped groove of extension rod 213 and forms a sliding, sealing engagement with housing 21, effectively preventing foreign matter from entering and interfering with the normal operation of the device.

[0103] When the external drive module 30 is started, it can provide the rotor magnet 24 with an external magnetic field that changes periodically over time. The rotor magnet 24 rotates under the action of the external magnetic field. After passing through the reducer 26, the speed is reduced and the torque is increased. The rotational motion is then converted into linear motion through the threaded transmission of the threaded rod 210. When the rotor magnet 24 rotates counterclockwise (as viewed from the left), it can drive the threaded rod 210 to rotate. However, due to the presence of the anti-rotation lug 22, the extension rod 213 cannot rotate and can only move relatively, thereby achieving the purpose of moving the extension rod 213 outward. The extension rod 213 drives the sliding clamp base 13 of the second sliding clamp below and the clamped fixing nail 12 to move through the first fixed foot 40, thereby achieving the purpose of bone lengthening.

[0104] It should be noted that, through the control of the drive module 30, the device of the present invention can achieve real-time feedback on the length of extension and shortening. The daily length and frequency of traction can be adjusted according to needs. The recommended traction frequency is 1 to 120 times per day, and the traction length is 1 to 2 mm per day. The introduction of the speed reducer 26 ensures a slow extension movement, which is more consistent with physiological characteristics. This embodiment uses a smaller threaded rod pitch (0.5 mm) to achieve more precise extension control.

[0105] ③Drive module 30:

[0106] In this embodiment, the driving module 30 is mounted on the first sliding fixture via the first driver connector 70 and the second driver connector 80 .

[0107] During installation, the first driver connector 70 and the second driver connector 80 should first be placed in corresponding positions on the sliding fixture base 13 of the first sliding fixture, and then the fixed legs should be installed. Both the first driver connector 70 and the second driver connector 80 are designed with through holes that align with the fixed leg mounting holes on the sliding fixture base 13. After installing the first fixed leg 40, the second fixed leg 50, and the third fixed leg 60, the first driver connector 70 and the second driver connector 80 can be positioned simultaneously. Finally, the driver module 30 is fixedly connected to the first driver connector 70 and the second driver connector 80 through a threaded connection to secure the driver module 30.

[0108] Specifically, in this embodiment, the first driver connector 70 and the second driver connector 80 are respectively located on the left and right sides of the first sliding fixture. The sliding fixture base 13 of the sliding fixture has an arched structure on both sides. The first driver connector 70 and the second driver connector 80 both use curved plates that match the arched structure as their base plates. The curvature of the curved plates matches the curvature of the arched structure, allowing for a tight fit and ensuring connection stability. Through holes are provided on the base plates of the first driver connector 70 and the second driver connector 80. The first driver connector 70 is aligned vertically with the fixed leg mounting hole on the left side of the sliding fixture base 13 of the first sliding fixture, while the through hole on the second driver connector 80 is aligned vertically with the fixed leg mounting hole on the right side of the sliding fixture base 13 of the first sliding fixture.

[0109] The internal structure of the driving module 30 is as follows Figure 6 As shown, the drive module 30 primarily includes an upper housing 31, a display screen 32, a lower housing 33, a reduction stepper motor 34, a motor base 35, a left fixing plate 36, a transmission gear 37, a right fixing plate 38, a three-jaw chuck 39, a magnet protection cover 310, a permanent magnet 311, a locking nut 312, a bolt 313, a first deep groove ball bearing 314, and a first bearing retaining ring 315. All components should be assembled externally before being placed and secured in the lower housing 33.

[0110] First, eight first deep groove ball bearings 314 are press-fitted into the left and right retaining plates 36 and 38, respectively. Four first deep groove ball bearings are press-fitted into each of the left and right retaining plates 36 and 38. Each first deep groove ball bearing 314 is positioned on one side by the retaining plate shoulder and axially positioned on the other side by the first bearing retaining ring 315. Both retaining plates have a total of eight holes and are installed in the same manner.

[0111] Subsequently, the gear shaft of the transmission gear 37 is passed through the left fixed plate 36 and the right fixed plate 38, and is also positioned by the shaft shoulder. Two points need to be noted here. First, the gear shaft connected to the reduction stepper motor 34 at the top is not fixed, which will be explained in subsequent operations; second, for the two gear shafts at the bottom connected to the three-jaw chuck 39, a platform is designed at the end of the connecting shaft of the gear shaft and the three-jaw chuck 39 (this embodiment uses an anti-rotation platform with a D-shaped shaft cross-section). The deflection angles of the platforms on both sides should be consistent to facilitate the installation of the permanent magnet 311. In order to ensure the stable operation of the transmission gear 37, bolts 313 and lock nuts 312 are installed on both sides of the fixed plate to achieve double protection.

[0112] Next, securely connect the permanent magnet 311 to the three-jaw chuck 39 with set screws. Securely connect the three-jaw chuck 39 to the bottom transmission gear shaft with set screws. Pass the magnet protective cover 310 through the two permanent magnets 311 and secure it to the right fixing plate 38 with strong glue. The motor base 35 is L-shaped, with the vertical portion secured to the left fixing plate 36 and the horizontal portion secured to the lower housing 33. Screws are used to secure the body of the reduction stepper motor 34 to the horizontal portion of the motor base 35. Both the output shaft of the reduction stepper motor 34 and the end of the top transmission gear shaft have a platform, which can be secured to the top transmission gear shaft with set screws.

[0113] Place the assembled components into the lower housing 33. A plurality of limit bars are provided on the inner surface of the bottom of the lower housing 33. The positions of the limit bars are as follows:

[0114] On the inner surface of the bottom of the shell, a first limiting strip is provided at the left and right edges along the projection outline of the deceleration stepping motor 34;

[0115] On the inner surface of the bottom of the housing, a plurality of threaded holes (four in this embodiment) are provided in the projection area of ​​the motor base 35. A waist-shaped groove is provided on the horizontal portion of the motor base 35. The threaded holes cooperate with the waist-shaped groove to securely connect the motor base 35 to the lower housing 33.

[0116] On the inner surface of the bottom of the shell, a second limiting strip is provided in the projection area of ​​the left fixing plate 36 and the right fixing plate 38 to ensure that the transmission gear 37 and the permanent magnet 311 do not interfere with the lower shell 33 .

[0117] Finally, the display screen 32 is connected to the upper housing 31 by screws, and the upper housing 31 and the lower housing 33 can be connected by glue or screws.

[0118] ④Permanent magnet drive principle:

[0119] In this embodiment, the relative positions of the permanent magnet 311 and the rotor magnet 24 are distributed as follows: Figure 10 As shown in the figure, the permanent magnets 311 in the drive module 30 and the rotor magnets 24 in the telescopic module 20 are both cylindrical neodymium iron boron magnets (no less than N45), magnetized in the radial direction. When the drive module 30 is turned on, the two permanent magnets 311 rotate at the same speed and in the same direction.

[0120] ⑤Working process:

[0121] The user can input control instructions on the display screen 32 according to the prescription of the attending physician. The control instructions mainly consist of parameters such as single-day traction frequency, single-day traction length, and total traction length. After the settings are completed, click the start button and the device will start running. If a problem occurs in the middle, the patient can click the lock button to stop all operations for inspection.

[0122] The working process of the device is as follows Figure 9 As shown. The display screen 32 serves as a user interaction interface for inputting control instructions. When the preset working moment is reached, the display screen 32 sends a signal to the control unit. The control unit first sends a switch signal to release the self-locking brake of the deceleration stepper motor 34, and then sends a step signal through the motor chip to drive the deceleration stepper motor 34 to work. The deceleration stepper motor 34 drives the two permanent magnets 311 to rotate synchronously, thereby generating an alternating magnetic field to drive the telescopic module 20 to work. The sensor installed on the telescopic module 20 can feed back the displacement signal to the control unit and the display screen 32 to detect whether the working state is normal. The relevant lines can pass through the openings on both sides of the lower shell 33.

[0123] In summary, the device of the present invention has the following advantages:

[0124] 1) The device of the present invention adopts the traditional support module design and fixes the external fixation pin through a sliding clamp, ensuring the reliability of fixation. The reliability is further improved by optimizing the contact mode of the linear guide rail.

[0125] 2) The device of the present invention proposes a new extension and shortening module. Through permanent magnet drive, it avoids the problems of severe heating and unstable speed of traditional motor drive, which helps to improve system stability and ensure the accuracy of extension and shortening. In addition, the telescopic module has dual functions of extension and shortening and can be used reciprocatingly.

[0126] 3) In the device of this invention, the drive module uses a permanent magnet as a generator, which provides a stronger driving magnetic field than electromagnetic drive and is simpler and more controllable. The reduced speed stepper motor employed features low-speed operation and frequent starts and stops, mimicking the natural growth process of bone, helping to shorten the bone transport treatment cycle. Furthermore, the device can be equipped with a sensor module to record and monitor extension and contraction lengths.

[0127] The above specific embodiments are used to illustrate the present invention rather than to limit the present invention. Any modifications and changes made to the present invention within the spirit of the present invention and the protection scope of the claims shall fall within the protection scope of the present invention.

[0128] The above are only preferred embodiments of the present invention, so any equivalent changes or modifications made according to the structure, features and principles of the patent application scope of the present invention are included in the scope of the patent application of the present invention.

Claims

1. A fully automatic bone lengthening and shortening device based on permanent magnet drive, characterized in that: include: A support module (10) comprises a linear guide rail (11) and a plurality of sliding fixtures arranged on the linear guide rail (11), wherein the sliding fixtures are used to install fixing pins (12); The telescopic module (20) is mounted on the sliding fixture to be fixed, and includes a power unit and a telescopic unit. The power unit includes a rotor magnet (24). The rotation of the rotor magnet (24) drives the telescopic end of the telescopic unit to extend and retract, thereby driving the sliding fixture to be movable to move on the linear guide rail (11); A driving module (30) is mounted on the same sliding fixture as the telescopic module (20), and includes two permanent magnets (311) located above the rotor magnet (24). The driving module (30) drives the rotor magnet (24) to rotate through a magnetic field generated by the permanent magnets (311); The telescopic module (20) further comprises a housing (21) and an anti-rotation lug (22); a power unit and a telescopic unit are mounted in the housing (21), and the anti-rotation lug (22) is mounted on one end of the housing (21); the power unit further comprises a rotor magnet sleeve (23), an input end gear (25), a reducer (26) and a connector (29); the rotor magnet sleeve (23) is sleeved on the outside of the rotor magnet (24), the rotor magnet sleeve (23) is connected to the reducer (26) via the input end gear (25), and an eccentric shaft is provided at one end of the connector (29), and the connector is connected to the planetary carrier output end of the reducer (26) via the eccentric shaft. The other end of the connecting member (29) is connected to the telescopic unit; the telescopic unit comprises a threaded rod (210), a sealing ring (211), a threaded sleeve (212) and an extension rod (213); the threaded rod (210) is connected to the connecting member (29), the threaded sleeve (212) is sleeved on the outer side of the threaded rod (210), one end of the extension rod (213) is sleeved on the outer side of the threaded sleeve (212), and the sealing ring (211) is embedded on the outer side; the other end of the extension rod (213) extends from the housing (21), and a groove adapted to the anti-rotation lug (22) is provided on the extension rod (213), and the sealing ring (211) is in sliding and sealing cooperation with the housing (21).

2. The fully automatic bone lengthening and shortening device based on permanent magnet drive according to claim 1 is characterized in that: The rotor magnet (24) and the two permanent magnets (311) are both cylindrical magnets, and the magnetization direction is radial; the axes of the two permanent magnets (311) and the rotor magnet (24) are parallel to each other, the two permanent magnets (311) are symmetrically arranged on both sides above the rotor magnet (24), and the rotation speed and direction of the two permanent magnets (311) are consistent.

3. The fully automatic bone lengthening and shortening device based on permanent magnet drive according to claim 1 is characterized in that: The fully automatic bone lengthening and shortening device further comprises a first fixing foot (40), a second fixing foot (50), a third fixing foot (60), a first driver connecting member (70) and a second driver connecting member (80); the second fixing foot (50) is detachably fixedly connected to the housing (21) of the telescopic module (20); a third bearing assembly is mounted on the top of the third fixing foot (60); an end of the rotor magnet sleeve (23) away from the reducer (26) is engaged with the third bearing assembly; a guide groove is provided on one side of the top of the first fixing foot (40); the extension rod (213) is inserted into the guide groove after extending from the housing (21); Each sliding fixture has fixed foot mounting holes on both sides, and the fixed foot mounting holes are opened in the vertical direction; the first fixed foot (40) is inserted into the fixed foot mounting hole on the sliding fixture to be moved; the second fixed foot (50) and the third fixed foot (60) are respectively inserted into the two fixed foot mounting holes of the same sliding fixture to be fixed; The upper and lower ends of the first driver connecting member (70) and the second driver connecting member (80) are respectively connected to the driving module (30) and the sliding clamp; the first driver connecting member (70) and the second driver connecting member (80) each include a base plate adapted to the shape of both sides of the sliding clamp, a through hole is provided on the base plate, the through hole is aligned with the fixed leg mounting hole up and down, and the base plate is detachably fixedly connected to the sliding clamp; the second fixed leg (50) and the third fixed leg (60) pass through the through hole above the corresponding fixed leg mounting hole and are then inserted into the fixed leg mounting hole.

4. The fully automatic bone lengthening and shortening device based on permanent magnet drive according to claim 1 is characterized in that: The driving module (30) further includes a display screen (32), a control unit, a deceleration stepping motor (34), a transmission gear (37) and a three-jaw chuck (39); the display screen (32) is used as an interactive interface, the display screen (32) is electrically connected to the control unit, the control unit is electrically connected to the deceleration stepping motor (34) and controls the deceleration stepping motor (34); the output shaft of the deceleration stepping motor (34) is connected to the driving wheel in the transmission gear (37), and the two output driven wheels in the transmission gear (37) are each connected to a three-jaw chuck (39), and each of the two three-jaw chucks (39) is mounted with a permanent magnet (311).

5. The fully automatic bone lengthening and shortening device based on permanent magnet drive according to claim 4 is characterized in that: The driving module (30) further comprises a driving module housing, a left fixing plate (36), a right fixing plate (38), a magnet protective cover (310), a locking nut (312) and a bolt (313); the left fixing plate (36) and the right fixing plate (38) are arranged on opposite sides of the transmission gear (37); a reduction stepping motor (34) is installed on the side of the left fixing plate (36) away from the right fixing plate (38); and a three-jaw chuck (39), a permanent magnet (311) and a magnet protective cover (310) are arranged on the side of the right fixing plate (38) away from the left fixing plate (36); The left fixed plate (36) and the right fixed plate (38) are connected in a limited position by a locking nut (312) and a bolt (313). The gear shaft of each driven wheel in the transmission gear (37) is mounted on the left fixed plate (36) and the right fixed plate (38) via a second bearing assembly. The magnet protection sleeve (310) is sleeved on the outside of the two permanent magnets (311) and is fixedly connected to the right fixed plate (38).

6. The fully automatic bone lengthening and shortening device based on permanent magnet drive according to claim 4 is characterized in that: The control unit controls the deceleration stepping motor (34) according to the setting of the pulling and shortening frequency of 1 to 120 times / day and the pulling length of 1.0 to 2.0 mm / day.

7. The fully automatic bone lengthening and shortening device based on permanent magnet drive according to claim 1 is characterized in that: The sliding fixture comprises a sliding fixture base (13), a sliding fixture upper cover (14), a flat washer (15) and a screw (16); the screw (16) is mounted on the bottom of the linear guide rail (11); the sliding fixture base (13) is movably connected to the linear guide rail (11) via the screw (16); a flat washer (15) is provided between the screw (16) and the linear guide rail (11); A sliding clamp upper cover (14) is lockably mounted on the upper portion of the sliding clamp base (13); the sliding clamp base (13) and the sliding clamp upper cover (14) are enclosed to form a plurality of holes, and the holes are used to accommodate fixing pins (12); fixing foot mounting holes are vertically opened on both sides of the sliding clamp base (13).

8. The fully automatic bone lengthening and shortening device based on permanent magnet drive according to claim 1 is characterized in that: The telescopic module (20) further comprises a displacement sensor for collecting the displacement of the telescopic end of the telescopic unit, and the displacement sensor is communicatively connected to the control unit of the driving module (30).

Images