Musculoskeletal ultrasound puncture navigator

Abstract

This invention belongs to the field of medical device technology, and specifically discloses a musculoskeletal ultrasound puncture navigation device, comprising: an ultrasound probe with a slit on its side, and a laser for emitting infrared light disposed inside the slit; a glove detachably connected to the side of the ultrasound probe; and a tensioning device including a fixing ring, a pressure ring, a pushing assembly, and a resetting assembly, wherein the fixing ring is detachably fitted onto the ultrasound probe near its bottom end, and the pressure ring is horizontally located at the top of the fixing ring. This invention, by placing a laser within the slit of the ultrasound probe, allows the laser to emit a single line of infrared light that completely overlaps with the ultrasound imaging plane during puncture operations, thereby directly projecting the virtual imaging plane onto the body surface. This solves the problem of the disconnect between the screen image and the actual body surface, intuitively marking the puncture path, significantly reducing the operational threshold, shortening the learning curve for physicians, and enabling novices to quickly achieve accurate punctures.

Description

Technical Field

[0001] This invention belongs to the field of medical device technology, and in particular relates to a musculoskeletal ultrasound puncture navigation device. Background Technology

[0002] The musculoskeletal ultrasound-guided puncture system is a medical device that uses a portable ultrasound imaging system as its core, combined with mechanical guidance, optical positioning, or infrared projection and other auxiliary positioning technologies. It enables precise puncture, drug administration, aspiration, biopsy, and minimally invasive treatment of lesions in the human musculoskeletal system. It is widely used in clinical departments such as pain management, rehabilitation medicine, orthopedics, sports medicine, rheumatology and immunology, and emergency medicine. With the rapid development of minimally invasive medicine and visualization diagnostic and treatment technologies, ultrasound-guided musculoskeletal puncture has gradually replaced traditional blind puncture procedures, becoming the mainstream technique for clinical pain management, intra-articular injection, nerve blocks, soft tissue lesion treatment, and aspiration of effusions / pus.

[0003] In traditional musculoskeletal aspiration procedures, physicians primarily rely on anatomical knowledge, clinical experience, and tactile judgment to determine the puncture path, depth, and target location. The lack of real-time visual guidance and precise path marking leads to problems such as needle deviation from the lesion, needle tip obscuration in ultrasound images, repeated punctures causing tissue damage, and accidental injury to blood vessels, nerves, and important anatomical structures. This not only increases patient suffering and surgical risks but can also lead to serious complications such as ineffective treatment, local bleeding, hematoma formation, infection, and nerve damage. For young physicians and primary care clinicians, ultrasound image interpretation, probe stability, needle angle control, and hand-eye coordination all require extensive and long-term clinical practice. The learning curve is long, the operation is difficult, and accuracy is hard to improve quickly, making it impossible to reach the level of a skilled physician in a short period. This severely restricts the widespread adoption and application of visual puncture technology in primary healthcare institutions.

[0004] Therefore, it is necessary to invent a musculoskeletal ultrasound puncture navigation device to solve the above problems. Summary of the Invention

[0005] To address the aforementioned problems, this invention provides a musculoskeletal ultrasound puncture navigation device, thereby solving one of the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a musculoskeletal ultrasound puncture navigation device, comprising: An ultrasonic probe, wherein a slit is provided on the side of the ultrasonic probe and a laser for emitting infrared rays is provided inside the slit; The glove is detachably attached to the side of the ultrasound probe; The tensioning device includes a fixed ring, a pressure ring, a pushing assembly, and a resetting assembly. The fixed ring is detachably sleeved on the ultrasound probe near its bottom end. The pressure ring is horizontally located on top of the fixed ring and is slidably sleeved on the ultrasound probe. There are two pushing assemblies, which are symmetrically arranged on both sides of the pressure ring to tension the patient's skin in both directions when the pressure ring moves downward. There are multiple resetting assemblies connected between the fixed ring and the pressure ring to push the pressure ring upward and reset it after it moves downward.

[0007] Furthermore, the pushing assembly includes a deflecting rod, a push rod, a tension spring, and a pushing mechanism. The deflecting rod is hinged to the side of the pressure ring. The push rod is horizontally fixedly connected to the bottom end of the deflecting rod. The tension spring is fixedly connected to the side of the deflecting rod near the ultrasound probe. A fixing block is fixedly connected to the end of the tension spring away from the deflecting rod. The fixing block is fixedly connected to the bottom of the pressure ring. The pushing mechanism is located between the deflecting rod and the fixing ring and is used to push the bottom end of the deflecting rod to deflect away from the ultrasound probe during the downward movement of the pressure ring.

[0008] Furthermore, the jacking mechanism includes a jacking block and a support roller. The jacking block is fixedly connected to the side of the deflection rod near the ultrasonic probe, and the width of the jacking block gradually decreases from top to bottom. The support roller is horizontally arranged on the side of the jacking block near the ultrasonic probe. Both ends of the support roller are rotatably connected to fixed rods, and the fixed rods are fixedly connected to the side of the fixed ring.

[0009] Furthermore, the reset assembly includes a telescopic rod and a reset spring. The telescopic rod is vertically fixed between the pressure ring and the fixed ring, and the reset spring is sleeved on the telescopic rod, with its two ends respectively fixedly connected to the surfaces of the telescopic rod near its two ends.

[0010] Furthermore, the length of the support roller is greater than the thickness of the top block, and the top block can always be in contact with the support roller under the tension of the tension spring on the deflection rod.

[0011] Furthermore, a rotating ring is rotatably connected to the top of the pressure ring, and an L-shaped pressure rod is fixedly connected to the top of the rotating ring.

[0012] Furthermore, the width and height of the vertical section of the pressure rod are greater than the width and height of the slit, respectively, and an annular sealing ring is fixedly connected to the side of the pressure rod near the ultrasonic probe. The sealing ring can fit against the side of the ultrasonic probe and completely surround the inner area of ​​the slit.

[0013] Furthermore, a silicone protective sleeve is detachably fitted onto the outer side of the push rod. The surface of the silicone protective sleeve has an axially oriented notch that matches the deflection rod. The length of the silicone protective sleeve is greater than the length of the push rod, and several anti-slip protrusions are evenly arranged on the outer side of the silicone protective sleeve.

[0014] Furthermore, a control button is provided on the surface of the ultrasonic probe at the bottom of the slit, and in the initial state, the control button is offset from the pressure ring, the fixing ring, and the reset assembly.

[0015] Furthermore, in the initial state, the bottom of the push rod can be higher than the bottom of the ultrasonic probe under the pushing force of the return spring on the pressure ring, and the top of the pressure ring is always lower than the bottom of the slit.

[0016] The technical effects and advantages of this invention are as follows: 1. This invention sets up a laser inside the slit of the ultrasound probe, so that during the puncture operation, the laser can emit a line of infrared light that is completely superimposed on the ultrasound imaging plane, thereby directly projecting the virtual imaging plane onto the body surface, solving the problem of the disconnect between the screen image and the actual body surface, intuitively marking the puncture path, greatly reducing the operation threshold, shortening the learning curve for doctors, and enabling novices to quickly achieve accurate puncture. 2. The present invention is equipped with a tensioning device. Through the cooperation of the pressure ring, the pushing component and the jacking mechanism, the two push rods can move in opposite directions when the pressure ring is pressed, thereby tightening the patient's skin, preventing skin laxity, displacement or wrinkling, ensuring that the body surface mark and the subcutaneous lesion location are accurately corresponded, effectively reducing puncture deviation and improving puncture accuracy. 3. This invention features an L-shaped pressure rod. When the ultrasonic probe is not in use, the pressure rod drives the rotating ring to rotate, thereby rotating the sealing ring on the pressure rod to a position directly opposite the slit. This creates a sealed protection for the slit and the infrared emission window, preventing contamination or blockage of the slit by coupling agent, blood, or disinfectant, thus ensuring clear infrared light projection and extending the service life of the equipment.

[0017] It should be understood that both the foregoing general description and the following detailed description are for illustrative purposes and do not necessarily limit the scope of this disclosure. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate the subject matter of this disclosure. Furthermore, the specification and drawings serve to explain the principles of this disclosure. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the specific embodiments of this disclosure or the prior art, the accompanying drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. The illustrative embodiments of this application and their descriptions are used to explain this application and do not constitute an improper limitation of this application.

[0019] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a three-dimensional schematic diagram of the tensioning device in this invention; Figure 3 This is a three-dimensional schematic diagram of the rotating ring, pressure rod, and sealing ring in this invention.

[0020] In the diagram: 1. Ultrasonic probe; 2. Slit; 3. Hand glove; 4. Fixing ring; 5. Pressure ring; 6. Deflection rod; 7. Push rod; 8. Tension spring; 9. Fixing block; 10. Top block; 11. Support roller; 12. Fixing rod; 13. Telescopic rod; 14. Return spring; 15. Rotary ring; 16. Pressure rod; 17. Sealing ring; 18. Silicone protective sleeve; 19. Anti-slip protrusion; 20. Control button. Detailed Implementation

[0021] To make the technical solutions and advantages of the embodiments of this application clearer, the exemplary embodiments of this application will be described in further detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not an exhaustive list of all embodiments. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other. This invention provides, for example Figures 1 to 3The illustrated musculoskeletal ultrasound puncture navigation device includes: an ultrasound probe 1, a glove 3, and a tensioning device. The ultrasound probe 1 is a portable high-frequency linear array ultrasound probe with a working frequency of 5-15MHz, suitable for imaging and puncture guidance of superficial musculoskeletal tissue. A long, narrow slit 2 is provided on the side of the ultrasound probe 1, extending along its length. A laser for emitting infrared light is sealed inside the slit 2. The laser is an infrared laser diode with a wavelength of 808-850nm, emitting a single-line infrared light. The infrared light plane completely overlaps with the imaging plane of the ultrasound probe 1, allowing precise projection of the ultrasound imaging plane onto the patient's skin surface, forming a clear puncture path mark. The width of the single-line infrared light emitted by the laser is ≤1mm, the projection distance is ≥30cm, the light is clear, and the collimation is good. The overlap error between the path mark formed on the skin surface and the ultrasound imaging plane is ≤0.5mm, ensuring accurate puncture path. A laser control button 20 is located at the bottom of the slit 2 on the surface of the ultrasound probe 1. The control button 20 is a touch-sensitive, waterproof button, and in its initial state... The control button 20 is staggered from the pressure ring 5, the fixing ring 4, and the reset assembly to avoid accidental triggering. Pressing the control button 20 turns the laser on and off, making operation convenient. The glove 3 is detachably connected to the side of the ultrasound probe 1. The glove 3 is made of medical-grade silicone and is detachably fitted to the upper middle part of the side of the ultrasound probe 1. The surface is provided with anti-slip texture and finger groove structure, conforming to the ergonomic design, making it easy for doctors to hold and improve the stability of the probe grip, preventing slippage during operation. The detachable design also facilitates individual cleaning, disinfection, and replacement. The tensioning device includes the fixing ring 4, the pressure ring 5, the pushing assembly, and the reset assembly. The fixing ring 4 is detachably fitted to the ultrasound probe 1 near the bottom. The pressure ring 5 is horizontally located at the top of the fixing ring 4 and slides on the ultrasound probe 1. There are two pushing assemblies, symmetrically arranged on both sides of the pressure ring 5, used to tighten the patient's skin in both directions when the pressure ring 5 moves downward. The reset assembly is connected between the fixing ring 4 and the pressure ring 5. There are 4-6 reset assemblies. The set is evenly distributed in a ring between the fixed ring 4 and the pressure ring 5, so that the force is uniform and the reset is smooth. It ensures that the pressure ring 5 does not tilt or jam during the up and down sliding process. It is used to push the pressure ring 5 to reset upward after it moves downward. The reset assembly includes a telescopic rod 13 and a reset spring 14. The telescopic rod 13 is vertically fixedly connected between the pressure ring 5 and the fixed ring 4. The reset spring 14 is sleeved on the telescopic rod 13, and the two ends of the reset spring 14 are fixedly connected to the surfaces of the telescopic rod 13 near the two ends respectively. The pushing assembly includes a deflection rod 6, a push rod 7, a tension spring 8, and a pushing mechanism. The deflection rod 6 is hinged to the side of the pressure ring 5. The push rod 7 is horizontally fixed to the bottom end of the deflection rod 6. The tension spring 8 is fixedly connected to the side of the deflection rod 6 near the ultrasonic probe 1. A fixing block 9 is fixedly connected to the end of the tension spring 8 away from the deflection rod 6. The fixing block 9 is fixedly connected to the bottom of the pressure ring 5. The pushing mechanism is located between the deflection rod 6 and the fixing ring 4. It is used to push the bottom end of the deflection rod 6 to deflect away from the ultrasonic probe 1 during the downward movement of the pressure ring 5. In the initial state, the bottom of the push rod 7 can be higher than the bottom of the ultrasonic probe 1 under the pushing force of the return spring 14 on the pressure ring 5, and the top of the pressure ring 5 is always lower than the bottom end of the slit 2. The jacking mechanism includes a jacking block 10 and a support roller 11. The jacking block 10 is fixedly connected to the side of the deflection rod 6 near the ultrasonic probe 1, and the width of the jacking block 10 gradually decreases from top to bottom. The support roller 11 is horizontally arranged on the side of the jacking block 10 near the ultrasonic probe 1. Both ends of the support roller 11 are rotatably connected to a fixing rod 12. The fixing rod 12 is fixedly connected to the side of the fixing ring 4. The length of the support roller 11 is greater than the thickness of the jacking block 10, and the jacking block 10 can always be in contact with the support roller 11 under the tension of the tension spring 8 on the deflection rod 6. Before use, attach the tensioning device consisting of the fixing ring 4, the pressure ring 5, the pushing component and the reset component to the bottom of the portable ultrasonic probe 1, and put the glove 3 on the side of the ultrasonic probe 1 to complete the assembly of the device. In use, apply medical ultrasound coupling agent evenly to the bottom of the ultrasound probe 1. Then, turn on the ultrasound probe 1 and laser by controlling the device. Next, hold the glove 3 and place the bottom of the ultrasound probe 1 against the skin surface of the patient's puncture site. Then, gently press down on the pressure ring 5. At this time, the pressure ring 5 can slide down along the ultrasound probe 1 under pressure. During this process, the return spring 14 and the telescopic rod 13 can be gradually compressed. As the pressure ring 5 moves downward, it can drive the deflection rods 6 on both sides and the top block 10 to move downward synchronously. At the same time, the push rod 7 gradually maintains contact with the patient's skin. As the top block 10 moves downward along the support roller 11, the top block 10, being a wedge-shaped structure, can drive the deflection rod 6 to deflect outward around the hinge point under the support of the support roller 11. During this process, the tension spring 8 is further stretched. As the deflection rod 6 deflects, the bottom ends of the two deflection rods 6 can drive the two push rods 7 to move horizontally away from each other. As the two push rods 7 move, they can cooperate with each other to automatically tighten the skin at the puncture site to both sides, preventing skin laxity, displacement, or wrinkling, and ensuring that the skin below the probe is flat and fixed. Once the patient's skin is stretched taut, the laser inside slit 2 emits a line of infrared light, which passes through slit 2 and is projected onto the patient's stretched skin surface, forming a puncture path marker that completely overlaps with the ultrasound imaging plane. At this time, the doctor can observe the subcutaneous lesions, blood vessels, nerves, and anatomical structures in real time through the ultrasound screen, determine the puncture target point, depth, and needle insertion angle, and accurately insert the needle along the infrared path marker on the skin surface. The ultrasound screen can clearly display the position of the needle tip in real time, ensuring that the puncture needle accurately reaches the target point to complete operations such as drug administration, injection, aspiration, or biopsy. After the operation is completed, the pressure ring 5 is released, and the reset spring 14 can push the pressure ring 5 upward under its own elastic force. As the pressure ring 5 is reset, the deflection rod 6 and the push rod 7 can also be automatically reset. As the pressure ring 5 is reset, the push rod 7 can be retracted inward to release the skin tension. Then the ultrasound probe 1 is removed from the patient's skin to complete the puncture operation.

[0022] like Figures 1 to 3 As shown, a rotating ring 15 is rotatably connected to the top of the pressure ring 5, and an L-shaped pressure rod 16 is fixedly connected to the top of the rotating ring 15. By providing a pressure rod 16, the pressure ring 5 can be easily pressed downwards by the pressure rod 16, and the presence of the rotating ring 15 allows doctors to adjust the position of the pressure rod 16 according to different usage habits, thereby improving the convenience of using the present invention.

[0023] like Figure 3 As shown, the width and height of the vertical section of the pressure rod 16 are greater than the width and height of the slit 2, and an annular sealing ring 17 is fixedly connected to the side of the pressure rod 16 near the ultrasonic probe 1. The sealing ring 17 can fit against the side of the ultrasonic probe 1, and the sealing ring 17 can completely surround the slit 2 in its inner area.

[0024] When the ultrasonic probe 1 is not in use, the pressure rod 16 can drive the rotating ring 15 to rotate, thereby rotating the sealing ring 17 on the pressure rod 16 to a position directly opposite the slit 2. This forms a sealed protection for the slit 2 and the infrared emission window, preventing contamination or blockage of the slit 2 by coupling agent, bloodstains, or disinfectant, thus ensuring clear infrared light projection and extending the service life of the equipment.

[0025] like Figure 1 and Figure 2 As shown, a silicone protective sleeve 18 is detachably fitted on the outer side of the push rod 7. The surface of the silicone protective sleeve 18 has an axial notch that matches the deflection rod 6. The length of the silicone protective sleeve 18 is greater than the length of the push rod 7, and several anti-slip protrusions 19 are evenly arranged on the outer side of the silicone protective sleeve 18. By providing a silicone protective sleeve 18, the silicone protective sleeve 18 can protect the push rod 7 during the process of stretching the patient's skin with the push rod 7, thereby preventing the push rod 7 from directly contacting the patient's skin and substances such as coupling agent, bloodstains, and disinfectant on the skin. After the puncture is completed, the silicone protective sleeve 18 can be removed separately for cleaning and disinfection, which improves the cleaning efficiency of the present invention. The anti-slip protrusions 19 on the silicone protective sleeve 18 can increase the friction between the silicone protective sleeve 18 and the patient's skin, thereby better supporting the patient's skin through the push rod 7.

[0026] Based on the embodiments in this disclosure, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of this disclosure.

[0027] In the description of this disclosure, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this disclosure and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this disclosure. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0028] In the description of this disclosure, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linkage" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this disclosure based on the specific circumstances.

[0029] Although preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

[0030] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A musculoskeletal ultrasound puncture navigator, characterized by, include: An ultrasonic probe (1) has a slit (2) on its side, and a laser for emitting infrared rays is provided inside the slit (2). The glove (3) is detachably attached to the side of the ultrasound probe (1); The tensioning device includes a fixed ring (4), a pressure ring (5), a pushing assembly, and a resetting assembly. The fixed ring (4) is detachably sleeved on the ultrasound probe (1) near the bottom. The pressure ring (5) is horizontally located on the top of the fixed ring (4) and is slidably sleeved on the ultrasound probe (1). There are two pushing assemblies, which are symmetrically arranged on both sides of the pressure ring (5) to tension the patient's skin in both directions when the pressure ring (5) moves downward. There are multiple resetting assemblies, which are connected between the fixed ring (4) and the pressure ring (5) to push the pressure ring (5) upward to reset after it moves downward.

2. The musculoskeletal ultrasound puncture navigator of claim 1, wherein: The pushing assembly includes a deflection rod (6), a push rod (7), a tension spring (8), and a pushing mechanism. The deflection rod (6) is hinged to the side of the pressure ring (5). The push rod (7) is horizontally fixed to the bottom end of the deflection rod (6). The tension spring (8) is fixedly connected to the side of the deflection rod (6) near the ultrasonic probe (1). A fixing block (9) is fixedly connected to the end of the tension spring (8) away from the deflection rod (6). The fixing block (9) is fixedly connected to the bottom of the pressure ring (5). The pushing mechanism is located between the deflection rod (6) and the fixing ring (4) and is used to push the bottom end of the deflection rod (6) to deflect away from the ultrasonic probe (1) during the downward movement of the pressure ring (5).

3. The musculoskeletal ultrasound puncture navigator of claim 2, wherein: The jacking mechanism includes a jack (10) and a support roller (11). The jack (10) is fixedly connected to the deflection rod (6) on the side near the ultrasonic probe (1), and the width of the jack (10) gradually decreases from top to bottom. The support roller (11) is horizontally arranged on the side of the jack (10) near the ultrasonic probe (1). Both ends of the support roller (11) are rotatably connected to a fixing rod (12), and the fixing rod (12) is fixedly connected to the side of the fixing ring (4).

4. The musculoskeletal ultrasound puncture navigator of claim 3, wherein: The reset assembly includes a telescopic rod (13) and a reset spring (14). The telescopic rod (13) is vertically fixed between the pressure ring (5) and the fixed ring (4). The reset spring (14) is sleeved on the telescopic rod (13), and the two ends of the reset spring (14) are fixedly connected to the surfaces of the telescopic rod (13) near the two ends.

5. The musculoskeletal ultrasound puncture navigator of claim 4, wherein: The length of the support roller (11) is greater than the thickness of the top block (10), and the top block (10) is always in contact with the support roller (11) under the tension of the tension spring (8) on the deflection rod (6).

6. The musculoskeletal ultrasound puncture navigator of claim 5, wherein: The top of the pressure ring (5) is rotatably connected to a rotating ring (15), and the top of the rotating ring (15) is fixedly connected to an L-shaped pressure rod (16).

7. The musculoskeletal ultrasound puncture navigator of claim 6, wherein: The width and height of the vertical section of the pressure rod (16) are greater than the width and height of the slit (2), and an annular sealing ring (17) is fixedly connected to the side of the pressure rod (16) near the ultrasonic probe (1). The sealing ring (17) can fit against the side of the ultrasonic probe (1), and the sealing ring (17) can completely surround the slit (2) in its inner area.

8. The musculoskeletal ultrasound puncture navigator of claim 7, wherein: The outer side of the push rod (7) is detachably fitted with a silicone protective sleeve (18). The surface of the silicone protective sleeve (18) is axially provided with a notch that matches the deflection rod (6). The length of the silicone protective sleeve (18) is greater than the length of the push rod (7), and a number of anti-slip protrusions (19) are uniformly provided on the outer side of the silicone protective sleeve (18).

9. The musculoskeletal ultrasound puncture navigator of claim 8, wherein: The ultrasonic probe (1) has a control button (20) located at the bottom of the slit (2) on its surface. In the initial state, the control button (20) is offset from the pressure ring (5), the fixing ring (4), and the reset assembly.

10. The musculoskeletal ultrasound puncture navigation device according to claim 9, characterized in that: In the initial state, the bottom of the push rod (7) is higher than the bottom of the ultrasonic probe (1) under the pushing force of the reset spring (14) on the pressure ring (5), and the top of the pressure ring (5) is always lower than the bottom of the slit (2).

Images