A sealing ring performance detection device for injection needle

Abstract

The application provides a sealing ring performance detection device of an injection needle, which comprises a support, a moving frame, a driving mechanism, a first force receiving part, a second force receiving part and a tension meter; when the tension meter moves upward, the first force receiving part drives the needle core to move upward, and at this time, the data of the tension meter is observed to realize the detection of the friction; when the tension meter moves downward, the supporting force of the needle core on the first force receiving part is converted into the pulling force of the second force receiving part on the tension meter through the transmission mechanism, so that the detection of the friction generated by the tension meter during the process that the needle core is pushed into the needle cylinder is realized; therefore, during the reciprocating movement of the needle core on the needle cylinder, when the value displayed by the tension meter deviates from the threshold value too much, the number of reciprocating movements accumulated by the needle core is the reference value of the service life of the injection needle; the application realizes the detection of the service life of the sealing ring, reduces the maintenance and replacement frequency of the detection device and the cost of the detection device through the tension meter which is low in price and simple in structure.

Description

Technical Field

[0001] This invention relates to the field of dyeing and printing testing equipment technology, specifically to a device for testing the performance of the sealing ring of an injection needle. Background Technology

[0002] In the textile industry, the production of fabrics requires many processes, including the dyeing process. When dyeing fabrics, auxiliaries and dyes need to be mixed by injecting them into a dye cup through a dye injection needle to create the desired color or to facilitate stable dyeing of the fabric. Since the mixed color is greatly affected by the amount injected by the dye injection needle, it is necessary to test the performance of the dye injection needle to ensure that it can inject stably and accurately.

[0003] During the performance testing of dye injection needles, it is necessary to test the service life of the dye injection needle (i.e., the service life of the sealing ring at the piston of the needle core). The common method for testing the service life of dye injection needles is to use a push-pull force gauge to push and pull the needle core in the syringe to make continuous reciprocating motion. If, during the cumulative number of reciprocating motions, the friction force between the sealing ring and the syringe deviates too much from the threshold (identified by the push-pull force gauge) during the uniform motion phase, it indicates that the sealing ring has reached its service life, and the cumulative number of reciprocating motions at this time is taken as the reference value for the service life of the sealing ring.

[0004] Because the number of reciprocating movements of the sealing ring is often large during life testing, and the push-pull force gauge is usually more sophisticated in its design than the pull force gauge, it is more expensive and more prone to damage during use compared to a conventional pull force gauge. Therefore, the push-pull force gauge requires more frequent maintenance and replacement, which limits its effectiveness in sealing ring life testing. To address these issues, there is an urgent need for a sealing ring performance testing device that uses a lower-cost, simpler pull force gauge as the testing component. Summary of the Invention

[0005] The purpose of this invention is to design a device for testing the sealing ring performance of injection needles, thereby solving the problems raised in the background art. To achieve the above objective, this invention provides the following technical solution: a bracket for mounting a syringe and driving a movable frame to reciprocate, a force gauge fixed to the movable frame, and a transmission mechanism mounted on the movable frame. The force gauge has a first force-receiving part and a second force-receiving part on its detection end. The needle core is connected to the first force-receiving part, and the first force-receiving part and the second force-receiving part are connected through the transmission mechanism. When the movable frame moves the force gauge upward, the first force-receiving part generates a pulling force on the force gauge; when the movable frame moves the force gauge downward, the first force-receiving part causes the second force-receiving part to generate a pulling force on the force gauge through the transmission mechanism.

[0006] Furthermore, the first force-receiving part includes a transition block slidably connected to the moving frame and used to push the needle core. When the moving frame drives the tension gauge to move downward, the transition block is connected to the detection end through the transmission mechanism. The transition block converts the force exerted by the needle core on the transition block into the tension force exerted by the second force-receiving part on the tension gauge through the transmission mechanism.

[0007] Furthermore, the transmission mechanism includes a first rack fixed to the end of the transition block and slidably connected to the outer wall of the moving frame, a gear set meshing with the first rack and mounted on the mounting groove of the moving frame, and a second rack meshing with the output end of the gear set and slidably connected to the inner wall of the moving frame. The second force-bearing part includes a thrust plate fixed to the second rack and a tension plate fixed to the detection end. When the moving frame drives the tension gauge to move downward, the thrust plate generates a thrust on the tension plate.

[0008] Furthermore, a pull rod is fixedly connected to the detection end, a slot is provided on the transition block, a lifting platform is provided at the end of the pull rod away from the tension gauge, the lifting platform is located inside the slot and there is always a gap between the lifting platform and the bottom of the slot, the pull rod passes through the top of the transition block and the pull rod is slidably connected to the transition block, and the tension plate is fixedly connected to the pull rod passing through the transition block.

[0009] Furthermore, there is a gap between the thrust plate and the tension plate, and the gear set includes a rotating shaft rotatably connected to the mounting groove. A first gear meshing with the first rack is fixedly connected to the rotating shaft, and a second gear meshing with the second rack is also fixedly connected to the rotating shaft. The tip circle diameter of the second gear is larger than that of the first gear.

[0010] Further, let the initial distance between the tension plate and the top of the transition block be h1; let the initial distance between the tension plate and the thrust plate be h2; when the tension plate and the thrust plate undergo relative displacement, let the equivalent average velocity of the tension plate be V1 and the equivalent average velocity of the thrust plate be V2. Therefore, 0 < h2 < h1(V2 - V1) / V1.

[0011] Further, the transition block is provided with a weight-reducing groove and a reinforcing rib plate.

[0012] Further, a telescopic member is fixedly connected to the top plate of the bracket, the output end of the telescopic member is fixedly connected to a moving plate, a plurality of the moving frames are fixedly connected to the moving plate, and the output end of the telescopic member penetrates through the top plate.

[0013] Further, two positioning plates are further provided on the bracket, a plurality of gaps are provided on the positioning plates, two ends of the syringe barrel are respectively clamped on two gaps vertically aligned on the two positioning plates, and the axis of the syringe barrel coincides with the axis of the detection end.

[0014] Further, a guide rod is fixedly connected between the top plate and the positioning plate, a sleeve is fixedly connected to the moving plate, and the guide rod penetrates through the moving plate and is slidably connected to the sleeve.

[0015] Further, a liquid storage tank is provided at the bottom of the bracket, and the needle tube of the syringe barrel is inserted into the liquid storage tank.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: when the moving frame is driven to move upward, the tensiometer will move upward, so that the first force-receiving part will drive the needle core to move upward. At this time, observing the data of the tensiometer can realize the detection of the frictional force; when the moving frame is driven to move downward, the frictional force between the sealing ring and the inner wall of the syringe barrel is the same as the supporting force of the needle core on the first force-receiving part, and the supporting force of the first force-receiving part is converted into the pulling force of the second force-receiving part on the tensiometer through the transmission mechanism, so as to realize the detection of the frictional force generated during the process of the tensiometer pushing the needle core into the syringe barrel; therefore, during the process of the needle core reciprocating on the syringe barrel, when the value displayed by the tensiometer deviates too much from the threshold value, the number of reciprocating movements accumulated by the needle core is the reference value of the service life of the injection needle. The present invention realizes the detection of the service life of the sealing ring while reducing the maintenance and replacement frequency of the detection device and the cost of the detection device by using a tensiometer with a relatively low price and a relatively simple structure. Description of the Drawings

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0019] Figure 2 This is an enlarged schematic diagram of the overall structure of the moving frame;

[0020] Figure 3 This is a magnified view of a portion of the moving frame;

[0021] Figure 4 This is a partial cross-sectional view of the moving frame.

[0022] The components are: 1. Moving plate; 2. Needle core; 3. Syringe; 4. Tension gauge; 5. Bracket; 6. Moving frame; 7. Telescopic component; 8. Second rack; 9. Push plate; 10. Pull plate; 11. Pull rod; 12. Groove; 13. Transition block; 14. Lifting platform; 15. First rack; 16. Mounting groove; 17. Slide rail; 18. Second gear; 19. First gear; 20. Rotating shaft. Detailed Implementation

[0023] To further illustrate the technical means and effects of the present invention in achieving its intended purpose, the following detailed description of the specific implementation methods, structures, features, and effects of the present invention, in conjunction with the accompanying drawings and preferred embodiments, is provided below.

[0024] Example: Common methods for testing the lifespan of injection needles typically involve using a push-pull force gauge to continuously push and pull the needle core in a reciprocating motion. If, during the cumulative number of push-pull cycles, the frictional force between the sealing ring and the syringe deviates significantly from a threshold value (the degree of deviation can be determined empirically and is not specifically limited here), it indicates that the sealing ring has reached its lifespan. The cumulative number of reciprocating cycles at this point is considered a reference value for the sealing ring's lifespan. However, push-pull force gauges are generally more complex and precise in design than pull force gauges. Therefore, compared to conventional pull force gauges, push-pull force gauges are more expensive and more prone to damage during use, requiring more frequent maintenance and replacement. Furthermore, the number of reciprocating cycles during lifespan testing is usually large, which limits the effectiveness of push-pull force gauges in testing the lifespan of sealing rings. Therefore, to reduce the frequency of maintenance and replacement and lower costs, this invention provides a sealing ring performance testing device that uses a lower-cost, simpler pull force gauge as the measuring element.

[0025] Please refer to Figures 1-4The present invention includes a bracket 5 for mounting a syringe 3 and driving a movable frame 6 to reciprocate, a force gauge 4 fixed to the movable frame 6, and a transmission mechanism mounted on the movable frame 6. The force gauge 4 has a first force-receiving part and a second force-receiving part on its detection end. The needle core 2 is connected to the first force-receiving part, and the first force-receiving part and the second force-receiving part are connected through the transmission mechanism. When the movable frame 6 moves the force gauge 4 upward, the first force-receiving part generates a pulling force on the force gauge 4; when the movable frame 6 moves the force gauge 4 downward, the first force-receiving part, through the transmission mechanism, generates a pulling force on the force gauge 4. The actuator causes the second force-receiving part to generate a pulling force on the tension gauge 4. Therefore, when it is necessary to detect the frictional force between the sealing ring and the inner wall of the syringe 3 during the process of the needle core 2 being withdrawn from the syringe 3, it is only necessary to drive the moving frame 6 upward. At this time, the tension gauge 4 will move upward, and the first force-receiving part will drive the needle core 2 upward. Observing the data of the tension gauge 4 at this time can realize the detection of frictional force. When it is necessary to detect the frictional force between the sealing ring and the inner wall of the syringe 3 during the process of the needle core 2 being pushed into the syringe 3, it is only necessary to drive the moving frame 6 downward. At this time, the first force-receiving part... The needle core 2 is pushed downwards. When the needle core 2 moves downwards at a constant speed, the frictional force between the sealing ring and the inner wall of the syringe 3 is the same as the supporting force of the needle core 2 on the first force-bearing part. The supporting force on the first force-bearing part is converted into the pulling force of the second force-bearing part on the tension gauge 4 through the transmission mechanism, thereby realizing the detection of the frictional force generated by the tension gauge 4 during the process of pushing the needle core 2 into the syringe 3. Therefore, in this invention, the tension gauge 4 can simultaneously detect the frictional force of the needle core 2 in both the withdrawal and insertion states of the syringe 3. Thus, when the value displayed by the tension gauge 4 deviates too much from the specified threshold during the reciprocating motion of the needle core 2 on the syringe 3, the cumulative number of reciprocating motions of the needle core 2 is the reference value for the service life of the injection needle. In addition, the number of reciprocating motions can be recorded by counting using an infrared counting sensor. Therefore, this invention realizes the detection of the sealing ring life while reducing the maintenance and replacement frequency of the detection device through the lower price and simpler structure of the tension gauge 4, and also reduces the cost of the detection device.

[0026] In this embodiment, the first force-bearing part includes a transition block 13 slidably connected to the movable frame 6 and used for pushing the needle core 2. When the movable frame 6 drives the tension gauge 4 to move downward, the transition block 13 is connected to the detection end through a transmission mechanism. The transition block 13 converts the force exerted by the needle core 2 on the transition block 13 into the pulling force of the second force-bearing part on the tension gauge 4 through the transmission mechanism. When the movable frame 6 moves upward, the tension gauge 4 moves upward, thereby driving the transition block 13 to move upward, and then driving the needle core 2 to move upward. At this time, the friction force can be detected by observing the data of the tension gauge 4. When the movable frame 6 is driven downward, the transition block 13 pushes the end of the needle core 2 downward. The supporting force of the needle core 2 on the transition block 13 is converted into the pulling force of the second force-bearing part on the tension gauge 4 through the transmission mechanism, thereby realizing the detection of the friction force generated by the tension gauge 4 during the process of pushing the needle core 2 into the syringe 3.

[0027] The transmission mechanism includes a first rack 15 fixed to the end of the transition block 13 and slidably connected to the outer wall of the moving frame 6, a gear set meshing with the first rack 15 and mounted on the mounting groove 16 of the moving frame 6, and a second rack 8 meshing with the output end of the gear set and slidably connected to the inner wall of the moving frame 6. The second force-bearing part includes a push plate 9 fixed to the second rack 8 and a pull plate 10 fixed to the detection end. When the moving frame 6 drives the tension gauge 4 to move downward, the push plate 9 generates a thrust on the pull plate 10. The connection can be made using a slider and a slide rail 17. Both the first rack 15 and the second rack 8 are equipped with sliders, and the inner and outer walls of the moving frame 6 are equipped with slide rails 17. Therefore, when the transition block 13 moves downward at a constant speed, the supporting force of the needle core 2 on the transition block 13 is applied to the tension plate 10 through the first rack 15, the gear set, the second rack 8 and the push plate 9, thereby generating a tension force on the tension plate 10, which in turn generates a tension force at the detection end of the tension gauge 4. At this time, the reading of the tension gauge 4 can reflect the magnitude of the friction force.

[0028] Furthermore, in the detection of friction when the needle core 2 is pushed back into the syringe 3, in order to make the reading of the tension gauge 4 as close as possible to the magnitude of the friction between the sealing ring and the syringe 3, an injection needle with a known friction force F1 can be introduced in advance to find the error between the reading and the friction force. Let the reading of the tension gauge 4 when the injection needle with the known friction force F1 is tested be F2, then the error value is F = F1 - F2 (when the needle core 2 is pushed back into the syringe 3, the tension gauge reading is less than the actual friction force). Therefore, after measuring the error value, when the injection needle with unknown friction force is placed in the bracket 5 and the friction force when the needle core 2 is pushed back into the syringe 3 is tested, then only the error value F needs to be added to the reading to obtain the actual friction force, thereby achieving accurate detection of the friction force when the needle core 2 is pushed back into the syringe 3. In addition, when testing the friction between the sealing ring and the inner wall of the syringe 3 during the process of the needle core 2 being withdrawn from the syringe 3, the same error value test can also be performed, thereby improving the measurement accuracy of the tension gauge 4 and improving the accuracy of the life test.

[0029] In this embodiment, a pull rod 11 is fixedly connected to the detection end, and a slot 12 is provided on the transition block 13. A lifting platform 14 is provided at the end of the pull rod 11 away from the tension gauge 4. The lifting platform 14 is located inside the slot 12, and there is always a gap between the lifting platform 14 and the bottom of the slot 12. The pull rod 11 passes through the top of the transition block 13 and is slidably connected to the transition block 13. The tension plate 10 is fixedly connected to the pull rod 11 that passes through the transition block 13, thereby realizing the conversion between the detection of the two frictional forces when the tension gauge 4 pushes back the needle core 2 and pulls out the syringe 3. In addition, in other embodiments, the pull rod 11 can be replaced by a non-elastic rope. In this case, the tension plate 10 is fixed on the non-elastic rope, and the gap between the lifting platform 14 and the bottom of the slot 12 can also be eliminated, that is, the lifting platform 14 abuts against the bottom of the slot 12, thereby improving the compactness of the overall structure and improving the response speed of the tension gauge 4, thereby improving the accuracy of the life test.

[0030] In this embodiment, a telescopic component 7 is fixedly connected to the top plate of the support 5. A movable plate 1 is fixedly connected to the output end of the telescopic component 7. Five movable frames 6 are fixedly connected to the movable plate 1, which can simultaneously detect five injection needles. The output end of the telescopic component 7 passes through the top plate, thereby realizing the lowering and raising of the movable frames 6. The support 5 is also provided with two positioning plates. The positioning plates have several notches. The two ends of the syringe 3 are respectively snapped into the two notches aligned vertically on the two positioning plates. The axis of the syringe 3 coincides with the axis of the detection end, thereby realizing the quick disassembly of the injection needle. The specific structure of the notches will not be elaborated in this article. It is only necessary to realize the snapping of the two ends of the syringe 3. A guide rod is fixedly connected between the top plate and the positioning plate. A sleeve is fixedly connected to the movable plate 1. The guide rod passes through the movable plate 1 and is slidably connected to the sleeve, ensuring the stability of the movement of the movable frames 6.

[0031] In this embodiment, in order to reduce the detection influence caused by the weights of the transmission mechanism and the transition block 13, their materials are both materials with low material density and high strength, such as aluminum profiles or plastics with high strength; and the transition block 13 is provided with a weight reduction groove and a reinforcing rib plate to further reduce the weight of the transition block 13 while ensuring its structural strength; in order to prevent the influence between states during the detection conversion of the two frictional forces when the needle core 2 is pushed back into the syringe barrel 3 and pulled out of the syringe barrel 3, usually there is a small gap between the thrust plate 9 and the tension plate 10. At this time, the gear set needs to adopt the form of a speed increasing gear set, that is, the gear set includes a rotating shaft 20 rotatably connected to the mounting groove 16. A first gear 19 meshing with the first rack 15 is fixedly connected to the rotating shaft 20. A second gear 18 meshing with the second rack 8 is also fixedly connected to the rotating shaft 20. The pitch circle diameter of the second gear 18 is larger than the pitch circle diameter of the first gear 19; in the initial state when the needle core 2 is pushed back into the syringe barrel 3 and the needle core 2 does not move (the frictional force is less than the maximum static frictional force), under the action of the gear set, the distance that the first rack 15 moves per unit time is less than the distance that the second rack 8 moves. At this time, the gap between the thrust plate 9 and the tension plate 10 will decrease. When the gap is zero and the transition block 13 moves downward at a constant speed, the magnitude of the frictional force will be reflected in the tensiometer 4;

[0032] And when the needle core 2 is pulled out of the syringe barrel 3 and before the needle core 2 overcomes the maximum static frictional force, that is, within a short time when the reading of the tensiometer 4 starts from zero, the transition block 13 moves downward relative to the tensiometer 4, and the first rack 15 also moves downward relative to the moving frame 6. Therefore, at this time, under the action of the gear set, the second rack 8 will move upward, so that the thrust plate 9 moves upward (when the needle core 2 slides, there is still a gap between the thrust plate 9 and the bottom of the tensiometer 4). At this time, although the tension plate 10 and the tensiometer 4 also move upward synchronously, as long as the transmission ratio of the gear set is greater than 1, the upward moving speed of the tension plate 10 will be less than the upward moving speed of the thrust plate 9. At this time, the gap between the thrust plate 9 and the tension plate 10 will increase. Therefore, there is no force acting on the tension plate 10 by the thrust plate 9 during this process. Subsequently, when the needle core 2 moves at a constant speed, the numerical value of the tensiometer 4 can reflect the magnitude of the frictional force between the sealing ring and the syringe barrel 3; in addition, let the initial distance between the tension plate 10 and the top of the transition block 13 be h1; let the initial distance between the tension plate 10 and the thrust plate 9 be h2; when the tension plate 10 and the thrust plate 9 have a relative displacement, let the equivalent average speed of the tension plate 10 be V1, and the equivalent average speed of the thrust plate 9 be V2. Among them, V1 is a controllable speed, that is, the telescopic speed of the telescopic rod, and V2 can be obtained according to the transmission ratio of the speed increasing gear set. Therefore, on the basis of known V1 and V2, when h1 and h2 satisfy 0 < h2 < h1(V2 - V1) / V1, it can be realized that before the tension plate 10 reaches the top of the transition block 13, the tension plate 10 and the thrust plate 9 have already abutted and a force acts, so that the detection of the frictional force when the needle core 2 is pushed back into the syringe barrel 3 can be realized.

[0033] Compared to the traditional method of using a push-pull force gauge 4 to test the service life of a sealing ring, using a force gauge 4 combined with a speed-increasing gear set can improve the accuracy of service life testing. The reasons are as follows: When using a push-pull force gauge 4 to test the service life of a sealing ring, because the testing of injection needles is done batch by batch, and each batch of injection needles is sampled from multiple products, the overall usage intensity of the push-pull force gauge 4 is relatively high. Therefore, when testing multiple batches or when the sampled quantity in a single batch is large, the push-pull force gauge 4 is prone to fatigue. This reduces the movement range of the needle core 2, leading to... The total distance the sealing ring travels in one reciprocating motion decreases. Since the total number of reciprocating motions (Z times) is generally large when the sealing ring reaches its service life, when the push-pull force gauge 4 becomes fatigued (it will not be replaced immediately because the accuracy requirement for the reading is not high, after all, cost reduction is the priority), the actual number of reciprocating motions the sealing ring travels after Z times of accumulation is actually less than Z, which will affect the life detection of the sealing ring. Moreover, this error will be more obvious when the syringe 3 is shorter, and the life detection effect will be worse.

[0034] (The specific explanation for the reduced movement range of the needle core 2 after the push-pull force gauge 4 becomes fatigued is as follows: During normal reciprocating motion, the moving frame 6 generally moves a fixed distance, that is, the moving frame 6 drives the push-pull force gauge 4 to move, thereby causing the sealing ring to reciprocate from the highest point to the lowest point of the syringe 3. When no fatigue deformation occurs, the sealing ring can reciprocate between the complete highest and lowest points. However, when fatigue occurs, taking the lowest point as the starting point, when the push-pull force gauge 4 moves upward, it must first overcome the maximum static friction before driving the sealing ring to move. Due to fatigue, the push-pull force gauge 4 will need to move upward a greater distance than when it is not fatigued before driving the sealing ring to move. At this time, there is a situation that reduces the total movement length, thereby reducing the range of movement of the needle core 2.) The sealing ring may not return to its highest point during subsequent movements. Similarly, during the downward push, the force gauge 4 needs to move downwards a further distance before moving the sealing ring. This also reduces the total distance traveled, preventing the sealing ring from returning to its lowest point. Therefore, during fatigue, the total distance traveled by the sealing ring in a reciprocating motion will decrease. After repeated accumulations, the lifespan may fall below Z, affecting lifespan detection. Furthermore, after multiple reciprocating motions, the contact area between the sealing ring and the syringe 3 becomes rough, potentially increasing the maximum static friction. This further causes the force gauge 4 to move upwards or downwards a further distance before moving the sealing ring, further impacting the accuracy of lifespan detection.

[0035] Therefore, when testing multiple batches or a large quantity of samples in a single batch, using the push-pull force gauge 4 can affect the detection of the sealing ring's lifespan. Based on this, this embodiment uses a combination of a speed-increasing gear set and the force gauge 4 to reduce the aforementioned inaccuracies in lifespan detection, thereby improving the accuracy of the sealing ring's lifespan detection. The reason is as follows: Due to the use of the speed-increasing gear set, during the process of the needle core 2 being pushed into the syringe 3, when the frictional force has not reached the maximum static frictional force, i.e., the transition block 13 is stationary; during this process, when the moving frame 6 moves downwards, the force gauge 4 also moves, i.e., the tension plate 10 moves downwards. Since the transition block 13 is stationary, the speed-increasing gear set causes the push plate 9 to move downwards, resulting in the downward speed of the push plate 9 being greater than the speed of the tension plate 10. When the push plate 9 contacts the tension plate 10, the push plate 9 will push the tension plate 10, and then the needle core 2 will begin to be pushed into the syringe 3; when the force gauge 4 also experiences fatigue, due to the presence of the speed-increasing gear... When the transmission ratio is greater than 2, compared to the case of directly using the push-pull force gauge 4, after the moving frame 6 descends a distance of L, the tension plate 10 moves down a distance greater than 2L, thereby increasing the relative displacement between the tension plate 10 and the push plate 9 by a distance greater than L. This causes the detection end of the force gauge 4 to be stretched downward by a distance greater than L, thus reducing the movement error. Specifically, if the push-pull force gauge 4 is used, its detection end needs to move a distance of L to overcome the maximum static friction and thus push the sealing ring to move. However, with the introduction of the speed-increasing gear set in this invention, the force gauge 4 does not need to move a distance of L to push the sealing ring to move. Moreover, the effect is more obvious when the transmission ratio of the speed-increasing gear set is large, thereby eliminating the problem of inaccurate lifespan caused by fatigue of the push-pull force gauge 4. As for the case where the maximum static friction of the needle core 2 increases after multiple reciprocating movements, the speed-increasing gear set in this application can still effectively eliminate its impact on lifespan detection.

[0036] Furthermore, as can be seen from the above analysis, when the speed-increasing gear set is introduced in this invention, the sealing ring will move when the needle core 2 moves less than L. Therefore, compared with the form of using a push-pull force gauge 4, the force gauge 4 in this application has higher sensitivity and can more timely reflect the entire actual movement process of the sealing ring.

[0037] In other embodiments, the bottom of the support 5 is provided with a liquid storage tank, and the needle tube of the syringe 3 is inserted into the liquid storage tank. Therefore, the present invention can also pour the dye that the injection needle needs to draw and push into the liquid storage tank, thereby detecting the friction between the sealing ring and the inner wall of the syringe 3 during actual use.

[0038] Working principle: When it is necessary to detect the friction between the sealing ring and the inner wall of the syringe 3 during the process of needle core 2 being withdrawn from the syringe 3, it is only necessary to drive the moving frame 6 upward through the telescopic component 7. At this time, the tension gauge 4 will move upward, thereby driving the transition block 13 upward, and then driving the needle core 2 upward. The friction can be detected by observing the data of the tension gauge 4. When it is necessary to detect the friction between the sealing ring and the inner wall of the syringe 3 during the process of needle core 2 being pushed into the syringe 3, it is only necessary to drive the moving frame 6 downward through the telescopic component 7. At this time, the transition block 13 will move downward against the end of the needle core 2. When the transition block 13 moves downward at a constant speed, the supporting force of the needle core 2 on the transition block 13 is transmitted through the first rack 15, the gear set, and the second rack 8. The push plate 9 acts on the pull plate 10, thereby generating a pulling force on the pull plate 10, which in turn generates a pulling force on the detection end of the force gauge 4. At this time, the reading of the force gauge 4 can reflect the magnitude of the friction force, thus realizing the detection of the friction force generated by the force gauge 4 during the process of the needle core 2 being pushed into the syringe 3. Therefore, during the reciprocating motion of the needle core 2 on the syringe 3, if the value displayed by the force gauge 4 deviates too much from the threshold, then the cumulative number of reciprocating motions of the needle core 2 is the reference value for the service life of the injection needle. Therefore, this invention realizes the life detection of the sealing ring while reducing the maintenance and replacement frequency of the detection device through the low-cost and simple structure of the force gauge 4, thereby reducing the cost of the detection device.

[0039] It should be noted that when a component is said to be "fixed to" another component, it can be directly attached to the other component or there may be an intervening component. When a component is said to be "connected to" another component, it can be directly connected to the other component or there may be an intervening component. The terms "upper," "lower," "left," "right," "front," "back," and similar expressions used in this document are for illustrative purposes only.

[0040] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A device for testing the performance of the sealing ring of an injection needle, characterized in that, The device includes a bracket (5) for mounting a syringe (3) and driving a movable frame (6) to reciprocate, a force gauge (4) fixed to the movable frame (6), and a transmission mechanism mounted on the movable frame (6). The force gauge (4) has a first force-receiving part and a second force-receiving part on its detection end. The needle core (2) is connected to the first force-receiving part, and the first force-receiving part and the second force-receiving part are connected through the transmission mechanism. When the movable frame (6) moves the force gauge (4) upward, the first force-receiving part generates a pulling force on the force gauge (4). When the frame (6) moves the force gauge (4) downward, the first force-receiving part causes the second force-receiving part to generate a pulling force on the force gauge (4) through the transmission mechanism; the first force-receiving part includes a transition block (13) slidably connected to the moving frame (6) and used to push the needle core (2); when the moving frame (6) moves the force gauge (4) downward, the transition block (13) is connected to the detection end through the transmission mechanism; the transition block (13) transfers the force of the needle core (2) on the transition block (13) through the transmission mechanism. The force is converted into the pulling force of the second force-bearing part on the tension gauge (4); the transmission mechanism includes a first rack (15) fixed to the end of the transition block (13) and slidably connected to the outer wall of the moving frame (6), a gear set meshing with the first rack (15) and installed on the mounting groove (16) of the moving frame (6), and a second rack (8) meshing with the output end of the gear set and slidably connected to the inner wall of the moving frame (6). The second force-bearing part includes a thrust plate (9) fixed to the second rack (8) and a thrust plate (9) fixed to the detection end. The tension plate (10) is moved downward by the moving frame (6) and the tension gauge (4), and the thrust plate (9) generates a thrust on the tension plate (10); the gear set includes a rotating shaft (20) rotatably connected to the mounting groove (16), the rotating shaft (20) is fixedly connected to a first gear (19) meshing with the first rack (15), and the rotating shaft (20) is also fixedly connected to a second gear (18) meshing with the second rack (8), the tip circle diameter of the second gear (18) is larger than the tip circle diameter of the first gear (19).

2. The device for testing the sealing ring performance of an injection needle according to claim 1, characterized in that, A pull rod (11) is fixedly connected to the detection end. A slot (12) is provided on the transition block (13). A lifting platform (14) is provided at the end of the pull rod (11) away from the tension gauge (4). The lifting platform (14) is located inside the slot (12) and there is always a gap between the lifting platform (14) and the bottom of the slot (12). The pull rod (11) passes through the top of the transition block (13) and the pull rod (11) is slidably connected to the transition block (13). The tension plate (10) is fixedly connected to the pull rod (11) that passes through the transition block (13).

3. The device for testing the sealing ring performance of an injection needle according to claim 2, characterized in that, The transition block (13) is provided with a weight-reducing groove and a reinforcing rib.

4. The device for testing the sealing ring performance of an injection needle according to claim 1, characterized in that, A telescopic component (7) is fixedly connected to the top plate of the bracket (5). A movable plate (1) is fixedly connected to the output end of the telescopic component (7). Several movable frames (6) are fixedly connected to the movable plate (1). The output end of the telescopic component (7) passes through the top plate.

5. The device for testing the sealing ring performance of an injection needle according to claim 4, characterized in that, The bracket (5) is also provided with two positioning plates, and the positioning plates are provided with several notches. The two ends of the syringe (3) are respectively engaged with the two notches of the two positioning plates aligned in the vertical direction. The axis of the syringe (3) coincides with the axis of the detection end.

6. The device for testing the sealing ring performance of an injection needle according to claim 5, characterized in that, A guide rod is fixed between the top plate and the positioning plate, and a sleeve is fixed on the moving plate (1). The guide rod passes through the moving plate (1) and is slidably connected to the sleeve.

7. The device for testing the sealing ring performance of an injection needle according to claim 1, characterized in that, The bottom of the support (5) is provided with a liquid storage tank, and the needle tube of the syringe (3) is inserted into the liquid storage tank.

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