Peripheral nerve plexus stimulation needle capable of automatically locking puncture depth

Abstract

The invention discloses a peripheral nerve plexus stimulation needle capable of automatically locking puncture depth, which relates to the technical field of nerve stimulation needles, and comprises a positioning ring seat used for being positioned above a part to be subjected to needle application; the adsorption assembly is fixedly connected below the positioning ring seat; the depth self-locking assembly is arranged in the positioning ring seat; the telescopic rods are arranged in a circumferential array, one end of each telescopic rod is hinged to the positioning ring seat, and the other end of each telescopic rod is hinged to the depth self-locking assembly; the nerve stimulation needle is arranged in the depth self-locking assembly in a penetrating manner, is driven by the depth self-locking assembly to adjust the needle setting depth, and is locked by the depth self-locking assembly after being adjusted to the target depth; the nerve stimulator is electrically connected with the nerve stimulation needle, the peripheral nerve plexus stimulation needle can achieve multiple self-locking, and the overall safety is improved.

Description

Technical Field

[0001] This invention relates to the field of nerve stimulation needle technology, specifically to a peripheral nerve plexus stimulation needle with automatic puncture depth locking. Background Technology

[0002] Peripheral plexus block is a key technique in modern anesthesiology and pain management. It involves precisely injecting local anesthetics around a target nerve plexus to achieve sensory and motor blockade in a specific area. Compared to general anesthesia, it offers significant advantages such as less disruption to the patient's physiological functions, better postoperative analgesia, and faster recovery. Currently, the mainstream clinical method for achieving precise nerve localization is neurostimulator-guided technology, which relies on the combined use of peripheral plexus stimulating needles and neurostimulators.

[0003] In existing technologies, nerve plexus stimulation puncture primarily relies on manual manipulation by a physician. The specific procedure involves the physician holding a nerve stimulation needle, percutaneously inserting it deeper while simultaneously applying weak electrical pulses to the needle via a nerve stimulator. As the needle tip approaches the target nerve, the electrical pulses stimulate the nerve, causing a visible contraction response in the specific muscle groups it innervates. By observing the intensity and location of the muscle response, combined with their anatomical knowledge and clinical experience, the physician determines the relative position of the needle tip to the target nerve and ultimately determines the optimal puncture depth and drug delivery site.

[0004] However, this traditional manual operation method has many limitations. On the one hand, the adjustment of the puncture depth relies entirely on the doctor's feel and experience, and the "step length" of needle insertion cannot be quantified, resulting in a high degree of subjectivity and uncertainty in the entire operation. Furthermore, the stability of the needle depends entirely on the doctor's continuous hand control throughout the puncture, positioning, and even indwelling drug administration process. However, during the long operation time, any involuntary movement of the patient, changes in tissue tension, and the doctor's own fatigue and hand tremors can easily cause the positioned needle tip to shift unexpectedly. On the other hand, doctors need to maintain a high degree of focus and a fixed, even awkward, posture for extended periods to stabilize the needle and continuously observe the patient's subtle reactions. This brings significant physiological fatigue and occupational injury risks to doctors.

[0005] Therefore, it is necessary to provide a peripheral nerve plexus stimulation needle with automatic puncture depth locking to solve the above problems. Summary of the Invention

[0006] To address the above problems, the present invention provides the following technical solution: a peripheral nerve plexus stimulation needle with automatic puncture depth locking, comprising: Positioning ring seat, used to position above the area to be needled; An adsorption component is fixedly connected to the lower part of the positioning ring seat; A deep self-locking component is disposed within the positioning ring seat; Multiple telescopic rods arranged in a circular array, with one end of each telescopic rod hinged to a positioning ring seat and the other end hinged to the depth self-locking assembly; A nerve stimulation needle is inserted into the depth self-locking assembly and driven by the depth self-locking assembly to adjust the insertion depth, and is locked by the depth self-locking assembly after being adjusted to the target depth; A nerve stimulator, electrically connected to the nerve stimulation needle.

[0007] Furthermore, as a preferred embodiment, the positioning ring seat includes a mounting ring and a limiting ring coaxially fixed below the mounting ring, the limiting ring being used to limit and support the telescopic rod; Each of the telescopic rods is provided with a ball joint at both ends, one end of which is connected to the mounting ring via a ball joint, and the other end is connected to the depth self-locking assembly via a ball joint.

[0008] Furthermore, preferably, the adsorption component includes: outer cylinder; The inner rod has external threads on its outer surface; The adsorption plate is fixedly connected to the end of the inner rod; The inner rod is inserted into the outer cylinder and connected to it by a threaded screw.

[0009] Furthermore, as a preferred embodiment, the depth self-locking component includes: Installation compartment; A self-locking seat is fixed inside the installation chamber, and an axial channel is provided in the center of the self-locking seat; The second limiting cylinder is equipped with a limiting block extending to the side. The second limiting cylinder is slidably disposed in the axial channel of the self-locking seat, axially limited by the limiting block. The first limiting cylinder has an external thread on its outer circumferential surface; A threaded cylinder is fixedly connected inside the installation chamber. The inner circumferential surface of the threaded cylinder is provided with an internal thread, and the external thread of the first limiting cylinder meshes with the internal thread of the threaded cylinder. The motor is fixedly installed inside the mounting compartment. A friction wheel is fixedly mounted on the output shaft of a motor. The periphery of the friction wheel contacts the outer surface of the first limiting cylinder and can drive the first limiting cylinder to rotate under the drive of the motor. The first limiting cylinder is rotatably connected to the second limiting cylinder; The nerve stimulation needle axially passes through the first limiting cylinder and the second limiting cylinder, and is fixedly connected to the second limiting cylinder; The nerve stimulation needle can rotate relative to the first limiting cylinder; When the first limiting cylinder rotates, it moves axially through the threaded engagement with the threaded cylinder, driving the second limiting cylinder and the nerve stimulation needle fixedly connected to it to move axially as a whole.

[0010] Furthermore, preferably, the tip of the nerve stimulation needle is an exposed conductive part; The nerve stimulation needle is covered with an insulating layer except for the needle tip.

[0011] Furthermore, preferably, the axial length of the exposed tip portion of the nerve stimulation needle is 5 mm to 8 mm; The maximum outer diameter of the second limiting cylinder is 5mm to 30mm.

[0012] Furthermore, as a preferred embodiment, the depth-locking component also includes: The gear is located below the friction wheel and is coaxially linked with the friction wheel. The gear has a toothed segment and at least one missing tooth arc segment on its periphery; The self-locking seat has an internal receiving groove; The rack is movably disposed within the receiving groove; A clamping block is fixedly connected to the first end of the rack, and the clamping block is adapted to apply a restraining force to the second limiting cylinder in the radial direction; The return spring has one end connected to a relatively fixed part inside the receiving groove, and the other end connected to the second end of the rack. The gear teeth mesh with the rack, and when the rack is driven to move towards the second limiting cylinder against the resistance of the return spring, the clamping block is driven to press the second limiting cylinder to achieve axial locking. When the missing tooth arc of the gear corresponds to the rack, the return spring drives the rack to reset, and the clamping block disengages from the second limit cylinder.

[0013] Furthermore, preferably, the clamping block is made of an elastic material.

[0014] Compared with the prior art, the present invention provides a peripheral nerve plexus stimulation needle with automatic puncture depth locking, which has the following beneficial effects: 1. In this invention, the insertion depth of the nerve stimulation needle can be adjusted at the millimeter level through the threaded engagement of the threaded cylinder and the first limiting cylinder. Combined with the pinpoint stimulation function of the nerve stimulation needle, doctors can obtain clear neural feedback, transforming the traditional experience-based operation that relies on personal touch into a quantifiable and standardized process, thereby improving the accuracy and success rate of nerve localization.

[0015] 2. This invention integrates a triple safety mechanism: first, an active gear and rack mechanical locking mechanism that powerfully locks the nerve stimulation needle after each step; second, a passive threaded self-locking mechanism achieved through the threaded engagement of the threaded cylinder and the first limiting cylinder; and third, a one-way limiting function achieved through the engagement of the positioning ring seat and the telescopic rod, allowing doctors to directly pull out the needle without any operation in case of an emergency.

[0016] 3. In this invention, the automated depth adjustment and stable mechanical support free doctors from the long-term, strenuous task of maintaining hand stability. Attached Figure Description

[0017] Figure 1 A schematic diagram of the planar structure of a peripheral nerve plexus stimulation needle with automatic puncture depth locking; Figure 2 A three-dimensional structural diagram of a peripheral nerve plexus stimulation needle with automatic puncture depth locking; Figure 3 This is a cross-sectional view of the adsorption component. Figure 4 A three-dimensional structural diagram of a depth-locking component; Figure 5 This is a cross-sectional view of the deep self-locking assembly. Figure 6 for Figure 5 Enlarged view of point A; In the diagram: 1. Nerve stimulator; 2. Positioning ring seat; 3. Adsorption assembly; 4. Nerve stimulation needle; 5. Depth self-locking assembly; 6. Telescopic rod; 21. Mounting ring; 22. Limiting ring; 31. Outer cylinder; 32. Inner rod; 33. Adsorption plate; 51. Mounting chamber; 53. First limiting cylinder; 54. Threaded cylinder; 55. Second limiting cylinder; 551. Limiting block; 56. Self-locking seat; 57. Motor; 58. Friction wheel; 59. Gear; 510. Rack; 511. Pressing block; 512. Return spring. Detailed Implementation

[0018] The terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such terms are interchangeable where appropriate; this is merely a way of distinguishing objects with the same attributes in the embodiments of this application. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion, so that a process, method, system, product, or apparatus that comprises a series of elements is not necessarily limited to those elements, but may include other elements not explicitly listed or inherent to those processes, methods, products, or apparatuses.

[0019] Example: In this embodiment of the invention, please refer to... Figures 1-6 A peripheral nerve plexus stimulation needle with automatic puncture depth locking is provided, comprising: Positioning ring seat 2 is used to position the area above the needle insertion site; The adsorption component 3 is fixedly connected to the lower part of the positioning ring seat 2; A depth self-locking component 5 is disposed within the positioning ring seat 2; Multiple telescopic rods 6 are arranged in a circular array, with one end of each telescopic rod 6 hinged to the positioning ring seat 2 and the other end hinged to the depth self-locking assembly 5; The nerve stimulation needle 4 is inserted into the depth self-locking component 5 and driven by the depth self-locking component 5 to adjust the needle depth, and locked by the depth self-locking component 5 after being adjusted to the target depth. The nerve stimulator 1 is electrically connected to the nerve stimulating needle 4.

[0020] During implementation, in the positioning phase, the doctor places the positioning ring seat 2 above the area on the patient's skin to be needled. Subsequently, by activating the adsorption assembly 3 fixed below the positioning ring seat 2, the entire device can be adsorbed onto the skin surface, thereby establishing a stable external reference frame. Then, through the extension and retraction of multiple telescopic rods 6, the depth self-locking assembly 5 reaches the designated position. These telescopic rods can be any of the following: hydraulic telescopic cylinders, pneumatic cylinders, or mechanical telescopic rods with spring damping.

[0021] During the puncture phase, the depth-locking component 5 drives the nerve stimulation needle 4, which passes through it, to move axially, thus achieving needle insertion. During this process, the nerve stimulator 1 can apply electrical pulses to the nerve stimulation needle 4, and the doctor can determine whether the needle tip is close to the target nerve plexus by observing the contraction response of specific muscles in the patient.

[0022] In addition, the depth self-locking component 5 has a built-in locking function that can prevent needle displacement caused by patient movement, changes in tissue tension, or accidental contact, thereby ensuring the continuous accuracy of treatment or diagnosis.

[0023] It should also be explained that this method reduces the difficulty of operation and the fatigue of doctors. Doctors no longer need to laboriously maintain the stability of the needle by hand for extended periods, and depth adjustment is now automatic instead of manual. This makes the surgical procedure simpler, reduces reliance on the experience of senior doctors, and significantly alleviates the physiological burden on doctors during long surgeries.

[0024] In this embodiment, the positioning ring seat 2 includes a mounting ring 21 and a limiting ring 22 coaxially fixed below the mounting ring 21. The limiting ring 22 is used to limit and support the telescopic rod 6. Each of the telescopic rods 6 has a ball joint at both ends, one end of which is connected to the mounting ring 21 via a ball joint, and the other end is connected to the depth self-locking assembly 5 via a ball joint.

[0025] It should be explained that multiple telescopic rods 6 are arranged in a circumferential array. One end of each rod is connected to the mounting ring 21 via a ball joint, and the other end is also connected to the depth self-locking component 5 that needs to be moved via a ball joint. The ball joint allows the connector to swing at multiple angles in three-dimensional space. The function of the limiting ring 22 is to provide limiting support for these telescopic rods 6, thereby restricting the downward movement of the depth self-locking component 5 but not restricting its upward movement, ensuring the stability of the depth self-locking component 5. When the needle needs to be withdrawn, especially in an emergency, the design of the limiting ring 22 allows the telescopic rods 6 to move upward without obstruction. In other words, when the doctor grasps the depth self-locking component 5 and pulls it upward, the limiting ring 22 will not create any obstruction.

[0026] In this embodiment, the adsorption component 3 includes: outer cylinder 31; The inner rod 32 has external threads on its outer surface; The adsorption plate 33 is fixedly connected to the end of the inner rod 32; The inner rod 32 is inserted into the outer cylinder 31 and is screwed into it.

[0027] The surface of the adsorption plate 33 can be pre-adhered with multiple layers of adhesive tape, and each layer can be peeled off after each use.

[0028] In this embodiment, the depth self-locking component 5 includes: Installation compartment 51; The self-locking seat 56 is fixed inside the installation chamber 51, and the self-locking seat 56 has an axial channel in the center; The second limiting cylinder 55 is equipped with a limiting block 551 extending to the side. The second limiting cylinder 55 is slidably disposed in the axial channel of the self-locking seat 56 via the limiting block 551. The first limiting cylinder 53 has an external thread on its outer circumferential surface; The threaded cylinder 54 is fixedly connected inside the installation chamber 51. The inner circumferential surface of the threaded cylinder 54 is provided with an internal thread, and the external thread of the first limiting cylinder 53 engages with the internal thread of the threaded cylinder 54. Motor 57 is fixedly installed inside mounting compartment 51; Friction wheel 58 is fixedly installed on the output shaft of motor 57. The periphery of friction wheel 58 contacts the outer surface of first limiting cylinder 53 and can drive first limiting cylinder 53 to rotate under the drive of motor 57. The first limiting cylinder 53 is rotatably connected to the second limiting cylinder 55; The nerve stimulation needle 4 axially passes through the first limiting cylinder 53 and the second limiting cylinder 55, and is fixedly connected to the second limiting cylinder 55. The nerve stimulation needle 4 can rotate relative to the first limiting cylinder 53; When the first limiting cylinder 53 rotates, it moves axially through the threaded engagement with the threaded cylinder 54, and drives the second limiting cylinder 55 and the nerve stimulation needle 4 fixedly connected to it to move axially as a whole.

[0029] First, the power for the entire assembly comes from the motor 57 fixed inside the installation chamber 51. When the puncture depth needs to be adjusted, the motor 57 starts, driving the friction wheel 58 fixedly mounted on its output shaft to rotate together.

[0030] Next, the power is transmitted through friction drive. The rotating friction wheel 58 contacts and presses its periphery against the outer surface of the first limiting cylinder 53. Relying on the friction force generated between the two, the first limiting cylinder 53 is driven to rotate synchronously.

[0031] The first limiting cylinder 53 has an external thread on its outside, which meshes with the internal thread of the threaded cylinder 54 fixed in the installation chamber 51. Since the threaded cylinder 54 is fixed, when the first limiting cylinder 53 is driven to rotate, it cannot spin in place, but will move in a straight line along its own axis, just like a screw being screwed into a nut.

[0032] This linear motion is transmitted to the nerve stimulation needle 4. The first limiting cylinder 53 is rotatably connected to the second limiting cylinder 55, allowing them to move together axially but rotate relative to each other. The second limiting cylinder 55 is positioned within the axial channel of the self-locking seat 56, and its lateral limiting block 551 restricts its rotation, allowing it to slide axially only within the channel. The nerve stimulation needle 4 passes through both limiting cylinders and is fixedly connected to the second limiting cylinder 55. Therefore, when the first limiting cylinder 53 moves axially, it pushes or pulls the second limiting cylinder 55, thereby directly driving the nerve stimulation needle 4, which is fixed to it, to advance or retract axially. Simultaneously, because the nerve stimulation needle 4 can rotate relative to the first limiting cylinder 53, it does not rotate itself during the movement.

[0033] It is worth mentioning that the thread drive has very high transmission accuracy. For every rotation of the output shaft of the motor 57, the nerve stimulation needle 4 will move a precise and fixed distance (i.e., the lead of the thread).

[0034] In mechanical engineering, when the lead angle of a thread is less than the friction angle of the thread pair, the thread possesses a self-locking characteristic. In this design, the threaded engagement between the first limiting cylinder 53 and the threaded cylinder 54 utilizes this principle. When the motor stops rotating, any downward force acting on the nerve stimulation needle 4 will attempt to drive the first limiting cylinder 53 to rotate in the opposite direction, causing it to move axially. However, due to the self-locking characteristic of the thread, the rotational torque generated by this axial force is insufficient to overcome the friction between the threads. Therefore, even if the motor is de-energized or loses torque in the non-locked state, the first limiting cylinder 53 will still be locked by the thread.

[0035] In this embodiment, the tip of the nerve stimulation needle 4 is an exposed conductive part; The nerve stimulation needle 4 is covered with an insulating layer except for the needle tip.

[0036] When an electrical signal is conducted through the nerve stimulation needle 4, the current is confined inside the needle body due to the insulation of the needle and cannot escape midway. The current can only be released when it reaches the needle tip, the only exposed opening, forming a localized electric field, thereby precisely stimulating the nerve tissue adjacent to the needle tip.

[0037] The axial length of the exposed needle tip portion of the nerve stimulation needle 4 is 5 mm to 8 mm; The maximum outer diameter of the second limiting cylinder 55 is 5mm to 30mm.

[0038] The needle tip is the only area where the current is released; the longer the tip, the larger the tissue area affected by the current; conversely, the smaller the area. Therefore, the 5mm to 8mm range is a golden range derived from extensive clinical practice. It aims to provide a balance between effectively detecting the target nerve and not compromising localization accuracy due to an excessively large stimulation area.

[0039] Secondly, the maximum outer diameter of the second limiting cylinder 55 is set to be between 5mm and 30mm. This dimension is mainly related to the volume and strength of the entire drive and guide module.

[0040] In this embodiment, the depth self-locking component 5 further includes: Gear 59 is located below friction wheel 58 and is coaxially linked with friction wheel 58; The gear 59 has a toothed segment and at least one missing tooth arc segment on its periphery; The self-locking seat 56 has an accommodating groove inside; The rack 510 is movably disposed within the receiving groove; A clamping block 511 is fixedly connected to the first end of the rack 510, and the clamping block 511 is adapted to apply a restraining force to the second limiting cylinder 55 in the radial direction; The return spring 512 has one end connected to a relatively fixed part inside the receiving groove, and the other end connected to the second end of the rack 510; The tooth segment of the gear 59 meshes with the rack 510. When the rack 510 is driven to move towards the second limiting cylinder 55 against the resistance of the return spring 512, it drives the pressing block 511 to press the second limiting cylinder 55 to achieve axial locking. When the missing tooth arc of gear 59 corresponds to rack 510, reset spring 512 drives rack 510 to reset, and clamping block 511 disengages from second limit cylinder 55.

[0041] When the motor starts and drives the gear 59 to rotate, once the teeth on its periphery rotate to the position of meshing with the rack 510, the rotational motion of the gear 59 will push the rack 510 to move linearly in the receiving groove. This movement will overcome the elastic force of the return spring 512 and drive the clamping block 511 fixed at the first end of the rack 510 to press tightly against the second limiting cylinder 55 in the radial direction.

[0042] Gear 59 continues to rotate under the drive of the motor. When the tooth segment passes through and its missing tooth arc rotates to the position corresponding to rack 510, the meshing relationship between gear 59 and rack 510 disappears. At this time, return spring 512 releases energy, rack 510 returns to its initial position, clamping block 511 also disengages from second limiting cylinder 55, the locking state is released, and second limiting cylinder 55 and nerve stimulation needle 4 return to a freely movable state.

[0043] In other words, motor 57 does not rotate continuously, but rather in steps. Each time it rotates a specific angle, the nerve stimulation needle 4 advances a short distance and is immediately locked. After the doctor confirms the position, the next instruction is given, the motor rotates another angle, the nerve stimulation needle 4 advances another short distance, and is locked again. This cycle repeats, achieving step-by-step control of the puncture depth.

[0044] Furthermore, the clamping block 511 is made of an elastic material.

[0045] The clamping block 511 is preferably made of polyurethane. It exhibits excellent wear resistance, mechanical strength, and friction properties, meeting the requirements of this component for high reliability, long service life, and strong locking force.

[0046] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A peripheral nerve plexus stimulation needle with automatic locking of the penetration depth, characterized in that The utility model relates to a kind of nerve stimulator (1), electrically connected the nerve stimulating needle (4). The positioning ring seat (2) includes mounting ring (21) and coaxially fixedly connected to mounting ring (21) below limit ring (22), limit ring (22) is used to limit support the telescopic rod (6); Each telescopic rod (6) is respectively equipped with ball joint at both ends, and one end is connected to mounting ring (21) by ball joint, and the other end is connected to depth self-locking assembly (5) by ball joint. The suction assembly (3) includes: Outer cylinder (31); Inner rod (32), which is provided with external threads on the outer surface; Suction disc (33), fixedly connected to the end of inner rod (32); 2. The automatic lock-out of penetration depth peripheral nerve plexus stimulation needle of claim 1, wherein, Wherein, the inner rod (32) is threaded into the outer cylinder (31) and cooperates with it. The depth self-locking assembly (5) includes:

3. The automatic lock-out of penetration depth peripheral nerve plexus stimulation needle of claim 1, wherein, Mounting bin (51); Self-locking seat (56), fixed in mounting bin (51), the self-locking seat (56) is centrally provided with axial passage; Second limiting cylinder (55) is configured with lateral extending limiting block (551), the second limiting cylinder (55) is axially limitedly and slidably arranged in the axial passage of self-locking seat (56) by limiting block (551); First limiting cylinder (53), which is provided with external threads on the outer circumferential surface; Threaded cylinder (54), fixedly connected in mounting bin (51), the inner thread is provided on the inner circumferential surface of threaded cylinder (54), the external thread of first limiting cylinder (53) is engaged with the inner thread of threaded cylinder (54); 4. The automatic lock-out of penetration depth peripheral nerve plexus stimulation needle of claim 1, wherein, Motor (57), fixedly arranged in mounting bin (51); Friction wheel (58), fixedly installed on the output shaft of motor (57), the periphery of friction wheel (58) contacts the outer surface of first limiting cylinder (53) and can drive first limiting cylinder (53) to rotate under the drive of motor (57); Wherein, the first limiting cylinder (53) is rotatably connected with the second limiting cylinder (55); The nerve stimulating needle (4) axially penetrates the first limiting cylinder (53) and the second limiting cylinder (55), and is fixedly connected to the second limiting cylinder (55); The nerve stimulating needle (4) can rotate relative to the first limiting cylinder (53); When first limiting cylinder (53) rotates, axial movement occurs by thread cooperation with threaded cylinder (54), and drives second limiting cylinder (55) and nerve stimulating needle (4) fixedly connected therewith to move axially as a whole. The needle tip portion of the nerve stimulating needle (4) is a bare conductive part; The nerve stimulating needle (4) is covered with an insulating layer except the needle tip portion. ​ ​ ​ ​ 5. The automatic lock-out of penetration depth peripheral nerve plexus stimulation needle of claim 4, wherein, ​ ​ 6. The automatic lock-out of penetration depth peripheral nerve plexus stimulation needle of claim 4, wherein, The axial length of the exposed needle tip portion of the nerve stimulation needle (4) is 5mm to 8mm; The maximum outer diameter of the second limiting cylinder (55) is 5mm to 30mm.

7. The automatic lock-out of penetration depth peripheral nerve plexus stimulation needle of claim 4, wherein, The depth self-locking assembly (5) further comprises: A gear (59) is located below the friction wheel (58) and coaxially linked with the friction wheel (58); The periphery of the gear (59) has a toothed segment and at least one toothless arc segment; A receiving groove is formed in the interior of the self-locking seat (56); A rack (510) is movably arranged in the receiving groove; A pressing block (511) is fixedly connected to the first end of the rack (510), and the pressing block (511) is adapted to apply a restraining force to the second limiting cylinder (55) in the radial direction; A return spring (512) has one end connected to a relatively fixed position in the receiving groove and the other end connected to the second end of the rack (510); When the toothed segment of the gear (59) meshes with the rack (510) and drives the rack (510) to move against the resistance of the return spring (512) in the direction of the second limiting cylinder (55), the pressing block (511) is pressed against the second limiting cylinder (55) to achieve axial locking; When the toothless arc segment of the gear (59) corresponds to the rack (510), the return spring (512) drives the rack (510) to reset, and the pressing block (511) is separated from the second limiting cylinder (55).

8. The automatic lock-out of penetration depth peripheral nerve plexus stimulation needle of claim 7, wherein, The pressing block (511) is made of elastic material.

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