Flexible needle puncture device

Abstract

The present invention discloses a flexible needle puncture device, comprising: a flexible needle assembly, which includes a flexible guide tube, a flexible hollow needle and a flexible push rod; a flexible needle puncture mechanism, which includes a first drive mechanism and a second drive mechanism; and a flexible needle bending mechanism, which includes a third drive mechanism and a bending guide rod with a guide groove. The flexible needle puncture device provided by the present invention can not only drive the flexible needle to realize the insertion and retraction functions, but also control the bending trajectory of the flexible needle and the insertion direction of the needle head, so that the flexible needle puncture device of the present invention can realize the puncture operation in a narrow space (such as MRI or CT closed-cell space), so that the imaging scan and the flexible needle insertion can be carried out synchronously, without the need to repeatedly move the patient into or out of the closed-cell cavity of MRI or CT during the operation, thereby reducing the operation time and improving the operation accuracy; the present invention can reduce the friction resistance between the flexible hollow needle and the flexible guide tube during insertion.

Description

Technical Field

[0001] The invention relates to the field of medical robots, and in particular to a flexible needle puncture device. Background Art

[0002] Needle insertion is one of the most commonly used methods in minimally invasive interventional surgery. In order to improve the accuracy and automation of intervention, robot-assisted surgery systems have been widely researched and developed, and needle insertion (needle insertion) mechanisms, as one of the essential core components of robot-assisted surgery systems, have also received high attention, especially for needle insertion mechanisms suitable for narrow spaces in closed-cell magnetic resonance imaging (MRI) systems or computed tomography (CT) systems. There is a wide demand for needle insertion mechanisms.

[0003] MRI is a mature medical diagnostic tool. MRI not only has excellent soft tissue contrast and spatial resolution in any direction, but also does not expose patients to ionizing radiation. Based on the results of MRI imaging diagnosis, doctors can determine the surgical target location, plan the surgical needle path, determine the needle insertion point, and pass the needle through the skin into the target anatomical structure, such as the joint space or nerve root, to inject contrast agents or painkillers. Doctors can also operate and control the needle to reach different internal organs, such as the prostate, breast, liver, and brain, to perform puncture biopsies, or perform minimally invasive radiofrequency or cryoablation treatments on cancerous sites. Since the horizontal closed-bore MRI scanner with an aperture of 60 cm is still the most commonly used, it is extremely difficult to perform surgical operations in such a narrow space. On the other hand, the commonly used puncture needles are mostly rigid needles, which makes it difficult to perform surgeries on certain parts or organs (such as the abdomen or liver) in the MRI closed-bore cavity because the rigid puncture needle may hit the inner wall of the MRI closed-bore cavity. Therefore, during the operation, the patient needs to be repeatedly moved in and out of the MRI scanner obturator to perform MRI scanning imaging or needle insertion, respectively. For example, Enrico Franco et al. published the document "Needle-Guiding Robot for Laser Ablation of Liver Tumors Under MRI Guidance" in IEEE / ASME TRANSACTIONS ON MECHATRONICS, VOL.21, NO.2 in April 2016, which discloses an MRI-guided liver tumor ablation surgical robot system. In order to perform the operation, the doctor has to enter the MRI scanning room after the MRI scan, move the patient out of the MRI obturator, and manually insert the ablation needle to perform the ablation operation based on the MRI imaging results; after the ablation operation is over and the ablation needle is withdrawn, the patient is moved into the MRI obturator for another scan to determine whether the ablation operation has met the surgical requirements. If not, the above surgical steps will be repeated until the surgical goal is achieved. This results in: 1) the patient needs to move in and out of the MRI obturator multiple times, causing the surgery to take a long time; 2) since the surgery and MRI imaging cannot be performed synchronously in real time, the accuracy of the needle's puncture path, position and direction cannot be guaranteed.

[0004] In order to overcome the shortcomings of conventional rigid needles, some solutions have been developed. For example, the StarBurst Xli enhanced semi-flexible radiofrequency ablation (RFA) device, a product designed specifically for interventional radiology by AngioDynamics, Inc. in the United States. It is a multifunctional radiofrequency ablation device. The ablation needle consists of a rigid segment and a flexible segment, so it is called semi-flexible, and the flexible segment can be bent up to 90 degrees in all directions, but the semi-flexible ablation device is not compatible with MRI. For another example, Samuel Byeongjun Park et al. published "A magnetic resonance image-guided breast needle intervention robot system: overview and design considerations" in Int J CARS (2017) 12: 1319–1331, DOI 10.1007 / s11548-017-1528-2 in 2017, which proposed a flexible needle intervention robot for the treatment of breast cancer that meets the MRI closed-cell space constraints. However, this robot also has the following defects: 1) The flexible needle can only be inserted along a pre-manufactured and bent guide tube (that is, the robot itself does not have the function of bending the needle), so the insertion direction and bending radius of the needle are predetermined and cannot be adjusted; 2) When the flexible needle is inserted into the pre-manufactured and bent guide tube, the needle tip is in contact with the inner wall of the guide tube, so it is easily obstructed and the insertion movement cannot be completed; 3) When the flexible needle is inserted, a large friction resistance is generated due to the contact between the outer wall of the needle and the inner wall of the guide tube.

[0005] For example, patent CN206499516U discloses a cannula flexible needle synchronous puncture mechanism based on gear transmission and patent CN107280767A discloses a cannula flexible needle puncture medical robot system, both of which can realize the puncture and retraction of the flexible needle, but still cannot achieve effective control of the bending trajectory and posture of the flexible needle.

[0006] Therefore, it is necessary to develop a mechanism that can not only drive the flexible needle to achieve the insertion and retraction functions, but also operate and control the bending state of the flexible needle and the insertion direction of the needle. Summary of the invention

[0007] The technical problem to be solved by the present invention is to provide a flexible needle puncture device in view of the deficiencies in the above-mentioned prior art, which can not only drive the flexible needle to realize the insertion and retraction functions, but also control the bending trajectory and needle insertion direction of the flexible needle according to the actual conditions of the surgical site and the working space during the operation.

[0008] To achieve the above object, the technical solution adopted by the present invention is: a flexible needle puncture device, comprising:

[0009] A flexible needle assembly, comprising a flexible guide tube with a hollow interior, a flexible hollow needle slidably inserted in the flexible guide tube, and a flexible push rod slidably inserted in the flexible hollow needle;

[0010] A flexible needle puncture mechanism, comprising a first drive mechanism for driving the flexible hollow needle and the flexible push rod as a whole to reciprocate in the flexible guide tube and a second drive mechanism for driving the flexible push rod to reciprocate in the flexible hollow needle;

[0011] And a flexible needle bending mechanism, which includes a third driving mechanism and a bending guide rod with a guide groove, wherein the guide groove has a guide shape trajectory for guiding the flexible guide tube to bend, and the guide shape trajectory has a curved trajectory segment, and the third driving mechanism is used to apply a force to the flexible guide tube so that the flexible guide tube fits with the guide groove to bend according to the guide shape trajectory, thereby making the flexible hollow needle and the flexible push rod in the flexible guide tube bend according to the guide shape trajectory.

[0012] Preferably, the first driving mechanism comprises a first bottom plate, a first front side plate connected to the first bottom plate, a first slider disposed on the first bottom plate and capable of reciprocating along the X direction, and a first power device for driving the first slider to reciprocate along the X direction;

[0013] The second driving mechanism includes a second base plate connected to the first slider, a second slider disposed on the second base plate and capable of reciprocating along the X direction, and a second power device for driving the second slider to reciprocate along the X direction.

[0014] Preferably, the rear end of the flexible guide tube is fixedly connected to the first front side plate, the rear end of the flexible hollow needle is fixedly connected to the first slider, and the front end of the flexible hollow needle is inserted into the flexible guide tube;

[0015] The rear end of the flexible push rod is fixedly connected to the second sliding block, and the front end of the flexible push rod is inserted into the flexible hollow needle.

[0016] Preferably, the curved guide rod is connected to the first front side plate; the guide groove is provided on the outer surface of the curved guide rod;

[0017] The guiding shape track of the guiding groove further includes a straight track segment tangentially connected to the front end of the curved track segment.

[0018] Preferably, the curved trajectory segment is a circular arc trajectory segment, a parabolic trajectory segment, or an elliptical arc trajectory segment;

[0019] The cross section of the guide groove is in an arc shape, a U shape, or a rectangular shape.

[0020] Preferably, the third driving mechanism includes a third base plate, a third slider arranged on the third base plate and reciprocating along the X direction, a third driving force device for driving the third slider to reciprocate along the X direction, a straightener fixedly mounted on the front end of the flexible guide tube, and a connecting rod having one end rotatably connected to the straightener and the other end rotatably connected to the third slider.

[0021] Preferably, the third driving mechanism further comprises at least one guide tube clamp fixedly sleeved between the front end and the rear end of the flexible guide tube and a spring connected between the guide tube clamp and the third sliding block.

[0022] Preferably, the straightener comprises a linear sleeve fixedly connected to the front end of the flexible guide tube, a connecting portion fixedly connected to the linear sleeve, and a connecting shaft arranged on the connecting portion for rotatably connecting to the connecting rod;

[0023] The guide tube clamp comprises a clamping sleeve fixedly sleeved on the flexible guide tube and a mounting rod fixedly connected to the clamping sleeve and used for connecting with the spring.

[0024] Preferably, the cross-sectional profile shapes of the bottom surfaces of the linear sleeve and the clamping sleeve for contacting the guide groove both match the cross-sectional profile shape of the guide groove.

[0025] Preferably, the flexible needle puncture device also includes a bracket, which includes a mounting base plate and a mounting side plate, the third drive mechanism of the flexible needle bending mechanism is arranged on the base plate, and the first drive mechanism of the flexible needle puncture mechanism is height-adjustably arranged on the mounting side plate.

[0026] The beneficial effects of the present invention are:

[0027] 1) The flexible needle puncture device provided by the present invention can not only drive the flexible needle to realize the insertion and retraction functions, but also control the bending trajectory, posture, and needle insertion direction of the flexible needle, so that the flexible needle puncture device of the present invention can realize the puncture operation in a narrow space (such as the MRI or CT closed-cell space), so that the imaging scan and the flexible needle insertion can be performed synchronously, without the need to repeatedly move the patient into or out of the closed-cell cavity of the MRI or CT during the operation, thereby reducing the operation time and improving the operation accuracy;

[0028] 2) In the present invention, the flexible hollow needle is initially inserted when the flexible guide tube is in a straight state and the needle tip of the flexible hollow needle extends out of the front end of the flexible guide tube. The flexible needle assembly is then bent as a whole. The flexible hollow needle is then inserted to the target position according to the lesion area. During this process, the flexible hollow needle can be smoothly inserted into the flexible guide tube, and there will be no large resistance due to the contact between the needle tip and the inner wall of the flexible guide tube, thereby affecting the insertion of the needle tip. This can reduce the friction resistance between the flexible hollow needle and the flexible guide tube. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a schematic structural diagram of the flexible needle puncture device of the present invention;

[0030] Figure 2 is an exploded view of the flexible needle puncture device of the present invention;

[0031] Figure 3 It is a structural schematic diagram of the flexible needle puncture mechanism of the present invention;

[0032] Figure 4 is an exploded view of the flexible needle puncture mechanism of the present invention;

[0033] Figure 5 It is a schematic diagram of the structure of the support of the present invention;

[0034] Figure 6 is a cross-sectional view of a flexible needle assembly of the present invention;

[0035] Figure 7 A perspective view and a side view of a curved guide rod of the present invention;

[0036] Figure 8 It is a schematic structural diagram of some components of the flexible needle bending mechanism of the present invention;

[0037] Fig. 9 is an exploded view of some components of the flexible needle bending mechanism of the present invention;

[0038] Fig.10 It is a schematic diagram of the structure of the straightener, the guide tube holder and the flexible guide tube of the present invention cooperating with each other;

[0039] Fig.11 An exploded view of the straightener and the guide tube holder of the present invention cooperating with the flexible guide tube;

[0040] Fig.12 It is a schematic structural diagram of the flexible needle bending mechanism of the present invention;

[0041] Figure 13(A)-13(C) Schematic diagrams of the structure of the flexible needle puncture device of the present invention in three different postures;

[0042] Fig.14 Schematic diagram of the working process of the flexible needle puncture device of the present invention.

[0043] Description of reference numerals:

[0044] 1—flexible needle assembly; 11—flexible guide tube; 12—flexible hollow needle; 13—flexible push rod;

[0045] 2—flexible needle puncture mechanism; 21—first drive mechanism; 22—second drive mechanism; 211—first bottom plate; 212—first front side plate; 213—first slider; 214—first power device; 215—first rear side plate; 221—second bottom plate; 222—second slider; 223—second power device; 224—second rear side plate; 2121—first opening; 2131—second opening; 2141—first motor; 2142—first screw rod; 2143—first screw rod nut; 2144—first guide rod; 2231—second motor; 2232—second screw rod; 2233—second screw rod nut; 2234—second guide rod;

[0046] 3—flexible needle bending mechanism; 31—third driving mechanism; 32—bending guide rod; 321—guiding groove; 311—third bottom plate; 312—third slider; 313—third driving force device; 314—straightener; 315—connecting rod; 316—guide tube clamp; 317—spring; 318—third front side plate; 319—third rear side plate; 3131—third motor; 3132—third screw rod; 3133—third screw rod nut; 3134—third guide rod; 3141—straight sleeve; 3142—connecting part; 3143—connecting shaft; 3161—clamping sleeve; 3162—mounting rod; 3211—curved track segment; 3212—straight track segment;

[0047] 4—bracket; 41—installation base plate; 42—installation side plate; 421—installation slot. DETAILED DESCRIPTION

[0048] The present invention is further described in detail below in conjunction with embodiments so that those skilled in the art can implement the invention with reference to the description.

[0049] It should be understood that the terms such as “having”, “including” and “comprising” used herein do not exclude the existence or addition of one or more other elements or combinations thereof.

[0050] Reference Figure 1-2 , this embodiment provides a flexible needle puncture device, comprising:

[0051] A flexible needle assembly 1, comprising a flexible guide tube 11 with a hollow interior, a flexible hollow needle 12 slidably inserted in the flexible guide tube 11, and a flexible push rod 13 slidably inserted in the flexible hollow needle 12;

[0052] The flexible needle puncture mechanism 2 includes a first drive mechanism 21 for driving the flexible hollow needle 12 and the flexible push rod 13 to reciprocate as a whole in the flexible guide tube 11 and a second drive mechanism 22 for driving the flexible push rod 13 to reciprocate in the flexible hollow needle 12;

[0053] And a flexible needle bending mechanism 3, which includes a third driving mechanism 31 and a bending guide rod 32 with a guide groove 321, the guide groove 321 has a guide shape trajectory for guiding the flexible guide tube 11 to bend, and the guide shape trajectory has a curved trajectory segment 3211, the third driving mechanism 31 is used to apply a force to the flexible guide tube 11, so that the flexible guide tube 11 fits with the guide groove 321 to bend according to the guide shape trajectory, so that the flexible hollow needle 12 in the flexible guide tube 11 is bent according to the guide shape trajectory.

[0054] The flexible needle puncture device of the present invention can not only drive the flexible needle to realize the insertion and retraction functions, but also control the bending trajectory, posture and needle insertion direction of the flexible needle. Specifically, in the present invention, the first driving mechanism 21 can drive the flexible hollow needle 12 and the flexible push rod 13 to move as a whole, so that the needle of the flexible hollow needle 12 extends out of the front end of the flexible guide tube 11, and then the bending trajectory and needle insertion angle of the flexible hollow needle 12 are controlled by the flexible needle bending mechanism 3, and the puncture and needle insertion action is further completed in cooperation with the first driving mechanism 21, and then the second driving mechanism 22 drives the flexible push rod 13 to move alone in the flexible hollow needle 12 to complete the injection action, such as implanting a marker seed or a drug capsule or an electrode for ablation surgery. Finally, the flexible needle assembly 1 is controlled to retract and return to its original position.

[0055] In the present invention, the first driving mechanism 21 and the second driving mechanism 22 are used to provide reciprocating driving power, and combined with the flexible needle bending mechanism 3 to guide the moving trajectory of the flexible hollow needle 12, the curved motion trajectory of the flexible hollow needle 12 can be controlled.

[0056] In the present invention, the bending radius of curvature of the flexible hollow needle 12 can be adjusted by controlling the fit between the flexible guide tube 11 and the curved track segment 3211 of the guide groove 321, so that the bending track and the needle insertion angle of the flexible hollow needle 12 are flexibly controllable.

[0057] In the present invention, the flexible needle assembly 1 is in a straight line shape as a whole when not affected by external force. In coordination with the flexible hollow needle 12, the flexible guide tube 11 is inserted when the flexible guide tube 11 is in a straight line state and the needle tip of the flexible hollow needle 12 extends out of the front end of the flexible guide tube 11. The flexible needle assembly 1 is then bent as a whole. Therefore, the flexible hollow needle 12 can be inserted into the flexible guide tube 11 smoothly without generating large resistance due to the contact between the needle tip and the inner wall of the flexible guide tube 11, thereby affecting the insertion of the needle tip.

[0058] The above is the overall concept of the present invention, and more detailed embodiments are provided below on the basis of the overall concept of the present invention to further illustrate the present invention.

[0059] Example 1

[0060] Reference Figure 3-4 In this embodiment, the first driving mechanism 21 includes a first base plate 211, a first front side plate 212 connected to the first base plate 211, a first slider 213 reciprocatingly arranged on the first base plate 211 along the X direction, and a first power device 214 for driving the first slider 213 to reciprocate along the X direction; the second driving mechanism 22 includes a second base plate 221 connected to the first slider 213, a second slider 222 reciprocatingly arranged on the second base plate 221 along the X direction, and a second power device 223 for driving the second slider 222 to reciprocate along the X direction.

[0061] The first driving mechanism 21 is used to drive the flexible hollow needle 12, the flexible push rod 13 and the second driving mechanism 22 to move as a whole along the X-axis direction, so that the needle tip of the flexible hollow needle 12 extends out of the front end of the flexible guide tube 11, and then drives the flexible hollow needle 12 to reach the target position after bending; the second driving mechanism 22 is used to drive the flexible push rod 13 to move alone in the flexible hollow needle 12 to complete the injection action, such as implanting marked seeds or drug capsules or electrodes for ablation surgery.

[0062] Among them, the first power device 214 and the second power device 223 can both adopt conventional power mechanisms that can provide linear driving force, such as screw motor drive mechanisms, belt pulley drive mechanisms, electric push rod mechanisms, cylinder mechanisms, etc. For the convenience of description, the following embodiments are described in detail by taking the screw motor drive mechanism as an example. Further, in order to ensure the linear motion of the first slider 213 and the second slider 222, a linear guide mechanism, such as a guide rod or a linear guide rail, is also required in a preferred embodiment. In this embodiment, a guide rod is selected for linear guidance.

[0063] In this embodiment, the first bottom plate 211 is connected to the first front side plate 212 and the first rear side plate 215, the first power device 214 includes a first motor 2141, a first screw rod 2142 drivingly connected to the first motor 2141, and a first screw rod nut 2143 threadedly matched with the first screw rod 2142, the first slider 213 is fixed to the first screw rod nut 2143, the two ends of the first screw rod 2142 are respectively connected to the first front side plate 212 and the first rear side plate 215, and two first guide rods 2144 are connected to the first front side plate 212 and the first rear side plate 215, and the first guide rod 2144 cooperates to pass through the first slider 213, and the two can slide relative to each other to achieve linear guidance and limit the rotation of the first slider 213. The first motor 2141 drives the first screw rod 2142 to rotate, thereby driving the first slider 213 to perform reciprocating linear motion on the first guide rod 2144 through the first screw rod nut 2143. Similarly, a second rear side plate 224 is provided on the second bottom plate 221, and the second power device 223 includes a second motor 2231, a second screw rod 2232 drivingly connected to the second motor 2231, and a second screw rod nut 2233 threadedly matched with the second screw rod 2232. The two ends of the second screw rod 2232 are respectively connected to the second rear side plate 224 and the first slider 213, and the second slider 222 is fixed to the second screw rod nut 2233. Two second guide rods 2234 are connected to the second rear side plate 224 and the first slider 213. The principle of the second power device 223 is the same as that of the first power device 214, and will not be repeated here.

[0064] Reference Figure 1 and Figure 5 In this embodiment, the flexible needle puncture device further comprises a bracket 4, the bracket 4 comprises a mounting bottom plate 41 and a mounting side plate 42, the third driving mechanism 31 of the flexible needle bending mechanism is arranged on the bottom plate, and the first driving mechanism (21) of the flexible needle puncture mechanism is arranged on the mounting side plate 42 in a height-adjustable manner. In a further preferred embodiment, a mounting groove 421 is provided on the mounting side plate 42 in a vertical direction, the first bottom plate 211 of the first driving mechanism 21 is arranged on the mounting side plate 42 by means of a screw and the mounting groove 421, and the mounting position of the flexible needle puncture mechanism 2 along the Z direction can be adjusted by adjusting the fixing position of the screw on the mounting groove 421, so as to adjust the overall mounting height of the flexible needle puncture mechanism 2 according to the size of the surgical site and the surgical space.

[0065] Continue to refer to Figure 2-3In this embodiment, the rear end of the flexible guide tube 11 is fixedly connected to the first front side plate 212, the rear end of the flexible hollow needle 12 is fixedly connected to the first slider 213, and the front end of the flexible hollow needle 12 is inserted into the flexible guide tube 11; the rear end of the flexible push rod 13 is fixedly connected to the second slider 222, and the front end of the flexible push rod 13 is inserted into the flexible hollow needle 12. Among them, the first front side plate 212 is provided with a first opening 2121, the end of the flexible guide tube 11 is fixedly inserted into the first opening 2121, the second slider 222 is provided with a second opening 2131, and the end of the flexible hollow needle 12 is fixedly inserted into the second opening 2131.

[0066] Reference Figure 6 , the flexible push rod 13, the flexible hollow needle 12, and the flexible guide tube 11 are coaxially arranged, and the diameters increase successively, and the inner walls are all smooth surfaces, so that they can slide smoothly with each other. In some embodiments, when the flexible push rod 13 needs to be used for liquid injection, a piston can also be provided at its end to ensure the smooth execution of the liquid injection function. In some embodiments, the flexible push rod 13, the flexible hollow needle 12, and the flexible guide tube 11 can all be made of nitinol or polyethylene or polypropylene or silicone or other flexible metal or plastic materials. In a preferred embodiment, they are all made of nitinol, which is a conventional nickel-titanium alloy. Due to its shape memory, superelasticity and biocompatibility characteristics, it has been widely used in the medical device industry.

[0067] In this embodiment, trajectory guidance and restriction are performed by the guide groove 321 on the bending guide rod 32, which can ensure that the flexible guide tube 11, the flexible hollow needle 12, and the flexible push rod 13 can be bent according to a predetermined trajectory, and can meet the requirements of the spatial position and orientation of the surgical site or surgical organ during the clinical needle insertion operation.

[0068] Continue to refer to Figure 1-2 , wherein the curved guide rod 32 is connected to the first front side plate 212, and the position setting of the curved guide rod 32 needs to satisfy: the flexible needle assembly can fit exactly with the guide groove 321 when bent. Figure 1 As shown in FIG. 2 , in one embodiment, the guide groove 321 is opened on the outer surface of the curved guide rod 32 and is directly below the flexible guide tube 11 .

[0069] Reference Figure 7In one embodiment, the guiding shape track of the guiding groove 321 also includes a straight track segment 3212 tangent to the front end of the curved track segment 3211. That is, the guiding groove 321 includes a curved track segment 3211 and a straight track segment 3212, the curved track segment 3211 is used to guide the bending of the curved track, and the straight track segment 3212 is used to keep the needle head of the flexible hollow needle 12 located at the front end in a straight line, so as to perform a smooth and accurate puncture action. Among them, the curved track segment 3211 can be a circular arc track segment, a parabolic track segment, or an elliptical arc track segment. Among them, the curvature radius of the curved track segment 3211 limits the actual minimum bending radius of the flexible guide tube 11, the flexible hollow needle 12, and the flexible push rod 13, so the minimum bending curvature radius allowed by the material and structure of the flexible guide tube 11, the flexible hollow needle 12, and the flexible push rod 13 must be smaller than the curvature radius of the curved track segment 3211. In a preferred embodiment, the curved track segment 3211 is a 1 / 4 arc with a radius of R, and the straight track segment 3212 is a straight line segment tangent to the end of the 1 / 4 arc with a length of L. In other embodiments, the curved track segment 3211 can be a different part of an arc, such as a 1 / 8 arc, or other types of curves.

[0070] In a preferred embodiment, the cross section of the guide groove 321 is in an arc shape, a U shape, or a rectangular shape. In this embodiment, the cross section of the guide groove 321 is a semicircular arc curve with a radius of r.

[0071] Reference Figure 8-9 as well as Fig.12 In this embodiment, the third driving mechanism 31 includes a third base plate 311, a third slider 312 disposed on the third base plate 311 and capable of reciprocating along the X direction, a third power device 313 for driving the third slider 312 to reciprocate along the X direction, a straightener 314 fixedly sleeved on the front end of the flexible guide tube 11, and a connecting rod 315 rotatably connected to the straightener 314 at one end and rotatably connected to the third slider 312 at the other end. In this embodiment, two connecting rods 315 are symmetrically arranged to ensure stability.

[0072] Among them, the third power device 313 can be a conventional power mechanism that can provide a linear driving force, such as a screw motor drive mechanism, a belt pulley drive mechanism, an electric push rod mechanism, a cylinder mechanism, etc. For the convenience of description, the screw motor drive mechanism is taken as an example for detailed description in this embodiment. Further, in order to ensure the linear motion of the third slider 312, a linear guide mechanism, such as a guide rod or a linear guide rail, is also required in a preferred embodiment. In this embodiment, a guide rod is selected for linear guidance. In this embodiment, a third front side plate 318 and a third rear side plate 319 are provided on the third base plate 311, and the third power device 313 includes a third motor 3131, a third screw rod 3132 driven and connected to the third motor 3131, and a third screw rod nut 3133 threadedly matched with the third screw rod 3132, and the two ends of the third screw rod 3132 are respectively connected to the third front side plate 318 and the third rear side plate 319, and the third slider 312 is connected to the third screw rod nut 3133. Two third guide rods 3134 are connected to the third front side plate 318 and the third rear side plate 319. The third guide rods 3134 pass through the third slider 312. The two can slide relative to each other to achieve linear guidance and limit the rotation of the third slider 312. The principle of the third power device 313 is the same as that of the first power device 214, which will not be repeated here.

[0073] Reference Figure 10-12 In this embodiment, the third driving mechanism 31 further includes at least one guide tube clamp 316 fixedly sleeved between the front end and the rear end of the flexible guide tube 11 and a spring 317 connected between the guide tube clamp 316 and the third slider 312. Each guide tube clamp 316 is configured with at least one spring 317, and in this embodiment, two springs 317 are configured.

[0074] Among them, the straightener 314 includes a linear sleeve 3141 fixedly connected to the front end of the flexible guide tube 11, a connecting part 3142 fixedly connected to the linear sleeve 3141, and a connecting shaft 3143 arranged on the connecting part 3142 for rotatably connecting to the connecting rod 315; the guide tube clamp 316 includes a clamping sleeve 3161 fixedly mounted on the flexible guide tube 11 and a mounting rod 3162 fixedly connected to the clamping sleeve 3161 for connecting to the spring 317.

[0075] In one embodiment, the end of the linear sleeve 3141 is fixedly connected to the front end of the flexible guide tube 11, and the linear sleeve 3141 is coaxially arranged with the flexible guide tube 11, and the inner diameter of the linear sleeve 3141 is very close to the outer diameter of the flexible hollow needle 12, so that the flexible hollow needle 12 can smoothly pass through the linear sleeve 3141, and the linear sleeve 3141 can clamp the flexible hollow needle 12, so that the flexible hollow needle 12 can be kept in a straight line and restore its rigidity after passing through the flexible guide tube 11 under the restriction of the linear sleeve 3141, so as to ensure that the puncture can be carried out smoothly. In another embodiment, the linear sleeve 3141 is fixedly sleeved on the flexible guide tube 11, and the inner diameter of the section of the flexible guide tube 11 in the linear sleeve 3141 is very close to the outer diameter of the flexible hollow needle 12, so that the section of the flexible guide tube 11 can also restrict the flexible hollow needle 12 to remain in a straight line and restore its rigidity.

[0076] The clamping sleeve 3161 and the flexible guide tube 11 can be fixed by interference fit, welding, screw connection or other methods.

[0077] In order to ensure that the flexible guide tube 11 fits the guide groove 321 on the curved guide rod 32 in the final bending posture, the cross-sectional profile shapes of the bottom surfaces of the linear sleeve 3141 and the clamping sleeve 3161 for contacting the guide groove 321 are matched with the cross-sectional profile shape of the guide groove 321. For example, in this embodiment, they are both arcs with a radius of r.

[0078] When the third power device 313 drives the third slider 312 to move along the X direction, the third slider 312 drives the connecting rod 315 and the lower end of the spring 317 to move along the X direction together. When the third slider 312 moves toward the side away from the curved guide rod 32, Fig.12 In the positive direction of the X-axis, under the restraint of the connecting rod 315 and the spring 317, the flexible guide tube 11 and the flexible hollow needle 12 and the flexible push rod 13 inside it will bend along the guide groove 321; when moving in the reverse direction, the flexible guide tube 11 and the flexible hollow needle 12 and the flexible push rod 13 inside it will be restored from the bent state to the straight state.

[0079] 13-14, in one embodiment, the working principle of the flexible needle puncture device of the present invention is:

[0080] S1. The first driving mechanism 21 drives the flexible hollow needle 12 and the flexible push rod 13 to move forward together in the flexible guide tube 11 until the needle tip of the flexible hollow needle 12 passes through the straightener 314. Fig.13A , which shows the posture of the flexible needle puncture device before the flexible needle assembly 1 is bent;

[0081] S2, the third driving mechanism 31 drives the third slider 312 to move toward the side away from the bending guide rod 32, and applies a force through the connecting rod 315 and the spring 317, so that the flexible guide tube 11 and the flexible hollow needle 12 and the flexible push rod 13 inside it are bent as a whole and reach a predetermined bending angle, refer to Fig. 13B and 13C; among them, Fig. 13B Shown is the posture of the flexible needle puncture device when the guide tube holder 316 is in contact with the curved guide rod 32, and the straightener 314 is not in contact with the curved guide rod 32; Fig. 13C Shown is the posture of the flexible needle puncture device when the guide tube holder 316 and the straightener 314 are both in contact with the curved guide rod 32;

[0082] S3, the first driving mechanism 21 continues to drive the flexible hollow needle 12 and the flexible push rod 13 to move forward in the flexible guide tube 11, and pass through the skin to reach the vicinity of the target;

[0083] S4, the second driving mechanism 22 independently drives the flexible push rod 13 to move forward to complete the target intervention, such as implanting a marker seed or a drug capsule or an electrode for ablation surgery;

[0084] S5, once the target intervention is completed, the second driving mechanism 22 independently drives the flexible push rod 13 to move backward and retract into the flexible hollow needle 12;

[0085] S6. The first driving mechanism 21 drives the flexible hollow needle 12 and the flexible push rod 13 to move backward together and return to the flexible guide tube 11, thereby completing the entire working process of the device.

[0086] Although the embodiments of the present invention have been disclosed as above, they are not limited to the applications listed in the specification and the implementation modes. They can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to specific details.

Claims

1. A flexible needle puncture device, characterized in that: include: A flexible needle assembly (1), comprising a flexible guide tube (11) with a hollow interior, a flexible hollow needle (12) slidably inserted in the flexible guide tube (11), and a flexible push rod (13) slidably inserted in the flexible hollow needle (12); A flexible needle puncture mechanism (2), comprising a first drive mechanism (21) for driving the flexible hollow needle (12) and the flexible push rod (13) as a whole to perform reciprocating motion in the flexible guide tube (11), and a second drive mechanism (22) for driving the flexible push rod (13) to perform reciprocating motion in the flexible hollow needle (12); and a flexible needle bending mechanism (3), comprising a third driving mechanism (31) and a bending guide rod (32) having a guiding groove (321), wherein the guiding groove (321) has a guiding shape track for guiding the flexible guide tube (11) to bend, and the guiding shape track has a curved track segment (3211), and the third driving mechanism (31) is used to apply a force to the flexible guide tube (11) so that the flexible guide tube (11) fits the guiding groove (321) to bend according to the guiding shape track, thereby causing the flexible hollow needle (12) and the flexible push rod (13) in the flexible guide tube (11) to bend according to the guiding shape track; The third driving mechanism (31) comprises a third base plate (311), a third slider (312) disposed on the third base plate (311) and capable of reciprocating along the X direction, a third power device (313) for driving the third slider (312) to reciprocate along the X direction, a straightener (314) fixedly sleeved on the front end of the flexible guide tube (11), and a connecting rod (315) having one end rotatably connected to the straightener (314) and the other end rotatably connected to the third slider (312); The third driving mechanism (31) further comprises at least one guide tube clamp (316) fixedly sleeved between the front end and the rear end of the flexible guide tube (11), and a spring (317) connected between the guide tube clamp (316) and the third sliding block (312); The straightener (314) comprises a linear sleeve (3141) fixedly connected to the front end of the flexible guide tube (11), a connecting portion (3142) fixedly connected to the linear sleeve (3141), and a connecting shaft (3143) provided on the connecting portion (3142) and used for being rotatably connected to the connecting rod (315); The guide tube clamp (316) comprises a clamping sleeve (3161) fixedly sleeved on the flexible guide tube (11) and a mounting rod (3162) fixedly connected to the clamping sleeve (3161) and used for connecting to the spring (317); The first driving mechanism (21) comprises a first bottom plate (211), a first front side plate (212) connected to the first bottom plate (211), a first sliding block (213) arranged on the first bottom plate (211) and capable of reciprocating along the X direction, and a first power device (214) for driving the first sliding block (213) to reciprocate along the X direction; The second driving mechanism (22) comprises a second base plate (221) connected to the first slider (213), a second slider (222) arranged on the second base plate (221) and capable of reciprocating along the X direction, and a second power device (223) for driving the second slider (222) to reciprocate along the X direction.

2. The flexible needle puncture device according to claim 1, characterized in that: The rear end of the flexible guide tube (11) is fixedly connected to the first front side plate (212), the rear end of the flexible hollow needle (12) is fixedly connected to the first sliding block (213), and the front end of the flexible hollow needle (12) is inserted into the flexible guide tube (11); The rear end of the flexible push rod (13) is fixedly connected to the second sliding block (222), and the front end of the flexible push rod (13) is inserted into the flexible hollow needle (12).

3. The flexible needle puncture device according to claim 2, characterized in that: The curved guide rod (32) is connected to the first front side plate (212); The guide groove (321) is opened on the outer surface of the curved guide rod (32), and the guide shape track of the guide groove (321) further includes a straight track segment (3212) tangentially connected to the front end of the curved track segment (3211).

4. The flexible needle puncture device according to claim 3, characterized in that: The curved trajectory segment (3211) is a circular arc trajectory segment, a parabolic trajectory segment, or an elliptical arc trajectory segment; The cross-section of the guide groove (321) is in the shape of an arc, a U, or a rectangle.

5. The flexible needle puncture device according to claim 1, characterized in that: The cross-sectional profile shapes of the bottom surfaces of the linear sleeve (3141) and the clamping sleeve (3161) for contacting the guide groove (321) both match the cross-sectional profile shape of the guide groove (321).

6. The flexible needle puncture device according to claim 5, characterized in that: The device further comprises a support (4), the support (4) comprising a mounting base plate (41) and a mounting side plate (42), the third driving mechanism (31) of the flexible needle bending mechanism (3) being arranged on the base plate, and the first driving mechanism (21) of the flexible needle puncture mechanism (2) being arranged on the mounting side plate (42) in a height-adjustable manner.

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