Automatic limiting detection device

Abstract

The invention relates to an automatic limiting detection device, and belongs to the field of medical instrument detection. The automatic limiting detection device comprises a water tank, a movable net racket used for limiting a detected sample in the water tank, a movable frame, a lifting mechanism used for driving the movable frame to ascend and descend, and a water level sensor module, wherein the water level sensor module comprises a water level sensor. The automatic limiting detection device is used for detecting the integrity of the initial package of the sterile medical instrument, the problem that the experimental position of a detected sample in water, especially the detected sample with a large expansion coefficient, is not uniform can be well solved, the experimental water depth of the detected sample can be dynamically adjusted by utilizing the automation of the device in the air inflation process of the experiment, and the detection accuracy is improved. And measurement errors caused by water level changes in the experiment process are avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of medical device detection, and specifically to an automatic limit detection device. Background Art

[0002] The basic characteristic of the primary packaging system of sterile medical devices is the ability to prevent microorganisms outside the packaging from entering the interior. The sealed packaging material provides a sterile and clean environment for the medical devices contained inside, maintaining the sterile state of the devices before use. Therefore, the primary packaging is regarded as a microbial barrier system. The integrity of the primary packaging material is fundamental to ensuring the safety of the finally sterilized medical devices during their shelf life. Therefore, the primary packaging is regarded as a component of sterile medical devices.

[0003] National Standard GB / T 19633.1—2015 "Final Sterilization of Medical Devices - Part 1: Requirements for Materials, Sterile Barrier Systems, and Packaging Systems" stipulates the requirements and test methods for primary packaging materials, preformed primary packaging systems, sterile barrier systems, and packaging systems that maintain the sterility of finally sterilized medical devices before intended use. YY / T 0681 is a series of standards for "Test Methods for Packaging Materials of Sterile Medical Devices" and can be used to verify the standard test methods and procedures that meet the requirements of Part 1 of GB / T 19633.

[0004] YY / T 0681.5 "Test Methods for Packaging of Sterile Medical Devices - Part 5: Detection of Gross Leaks by the Internal Pressure Method (Bubble Method)". This test method injects gas into the interior of the packaging to form a certain positive pressure condition, and checks whether there are signs of leakage on the surface of the packaging, that is, to prove whether there are risk defects in the tested packaging bag. Typical signs of leakage are the appearance of a bubble flow on the surface of the packaging material. Therefore, during the experiment, the sample needs to be completely immersed in the medium water for observation. Defect holes on the surface of the packaging material will generate bubbles under a certain internal pressure, and the pressure point when the first bubble is generated is the breathing point pressure of the air hole. According to the liquid pressure formula P = ρgh, the interfering factor affecting the breathing point pressure of the same air hole is the longitudinal position h of the test sample in the medium water. The closer the air hole is to the water surface, the smaller h is, and the smaller the reaction force of the water pressure on the breathing point pressure; when the distance from the air hole to the water surface is deeper, the reaction force of the pressure generated by the medium water on the breathing point pressure of the air hole is greater.

[0005] According to the theoretical pressure formula, good control of the position of the sample in water during the experiment can reduce the uncertainty of the measurement result and reduce the measurement error.

[0006] At present, the measure for fixing the position of the sample in water during this detection work is one-time limit fixing. When the test is inflated, the packaging will expand underwater. As the specifications of different samples or the expansion volume coefficients are different, the initial water level height will change, making it difficult to control the sample at the water depth required by the standard, or it is difficult to control the underwater depth uniformly among parallel samples, which becomes an uncertain factor in the test results.

[0007] Based on this, the present invention is proposed. Summary of the Invention

[0008] In view of the deficiencies of the prior art, the present invention provides an automatic limit detection device, and its technical solution is as follows:

[0009] An automatic limit detection device includes a water tank, a movable net racket for limiting the sample to be tested in the water tank, a moving frame for connecting the movable net racket, a lifting mechanism for driving the moving frame to lift and lower, and a water level sensor module for controlling the lifting mechanism. The water level sensor module includes a water level sensor installed on the moving frame.

[0010] As a further solution of the present invention, the lifting mechanism includes a stepping motor, a synchronous shaft driven by the stepping motor to rotate, and two lead screws. A bevel gear transmission or a worm and worm gear combination is used between the stepping motor and the synchronous shaft; a bevel gear transmission is used between the synchronous shaft and the lead screw, and a ball screw is formed between the lead screw and the moving frame by installing a ball nut.

[0011] As a further solution of the present invention, it further includes multiple guide rods. Through holes matching the guide rods are provided at the ends of the moving frame, and the ends of the moving frame are slidably connected to the guide rods.

[0012] As a further solution of the present invention, a moving marking needle is slidably connected to the guide rod.

[0013] As a further solution of the present invention, the movable net racket includes a net-shaped net plate. A fixed shaft is fixedly connected to the tail end of the net plate, a lock is provided at the head end of the net plate, the tail end of the net plate is hinged to the moving frame through the fixed shaft, and the head end of the net plate is connected to the moving frame through the lock.

[0014] As a further solution of the present invention, a water level scale is slidably connected to the moving frame. The water level sensor is fixed on the water level scale, and the lower end of the water level sensor is aligned with the zero scale line of the water level scale.

[0015] As a further solution of the present invention, the water level sensor includes a columnar sensor body. A confluent end in the shape of "︸" is arranged at the lower end of the sensor body. A hydrophobic line array is arranged on the outer side wall of the sensor body. The hydrophobic line array is composed of a plurality of linear hydrophobic coatings arranged along the height direction of the sensor body, and the hydrophobic coatings are arranged at equal intervals. An electrode one is arranged on one side of the confluent end at the lower part of the sensor body, and an electrode two is arranged on the other side of the confluent end.

[0016] As a further solution of the present invention, a wave-proof ring is also sleeved on the lower part of the sensor body, and the electrode one, the electrode two and the confluent end are all located inside the wave-proof ring.

[0017] When conducting the integrity detection of the primary packaging of sterile medical devices in the current laboratory, the technical shortcoming lies in the position control of the tested sample in water. The stability of manual control by the operator is the most unfavorable. For such non-fixed constraints, the detection data is significantly affected by the pressure change of the water level of the tested sample, and the existing operation errors are relatively prominent. For the fixed constraint method, although it can solve the measurement error caused by the water level deviation of the tested sample during the experiment, this form of processing method fails to fully solve the influence of the inflation expansion of the tested sample on the water level in the water tank. As the tested sample in the water expands, the water level in the water tank rises. Although the position of the tested sample marked before the experiment remains unchanged, the immersion depth of the tested sample deviates due to the change of the water level in the water tank, resulting in such measurement errors.

[0018] Applying the automatic limit detection device of the present invention can avoid a type of error caused by manual operation and a type of error of the fixed type. Through the fixation and dynamic adjustment of the tested sample, the tested sample always remains at a constant water level during the experiment, solving the uncertainty caused by water pressure during the experiment, thereby improving the accuracy of the experimental measurement results.

[0019] Compared with the prior art, the beneficial effects of the present invention are:

[0020] The automatic limit detection device of the present invention is used for the integrity detection of the primary packaging of sterile medical devices, and can preferably solve the problem that the experimental positions of the tested samples in water are not unified. Especially for the tested samples with a relatively large expansion coefficient, during the inflation process of the experiment, by using the automation of the device, the experimental water depth of the tested sample can be dynamically adjusted to avoid measurement errors caused by water level changes during the experiment. Description of the Drawings

[0021] Figure 1 It is a structural schematic diagram of an automatic limit detection device of the present invention;

[0022] Figure 2 It is a structural schematic diagram of the movable net racket of the present invention;

[0023] Figure 3 Schematic diagram of the distribution of the water level sensor and water level scale of the present invention;

[0024] Figure 4 Schematic diagram of the structure of the water level sensor of the present invention;

[0025] Figure 5 Schematic diagram of the structure of the sensor body of the present invention. Specific embodiments

[0026] The present invention will be described in detail below in conjunction with specific embodiments. The following described embodiments are only a part of the embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative efforts fall within the scope of protection of the present invention.

[0027] Embodiment 1

[0028] As Figure 1 shown, an automatic limit detection device includes a water tank 1, a movable net racket 6 for limiting the measured sample in the water tank 1, a moving frame 9 for connecting the movable net racket 6, a lifting mechanism for driving the moving frame 9 to lift and lower, and a water level sensor module for controlling the lifting mechanism. The water level sensor module includes a water level sensor 5 installed on the moving frame 9.

[0029] As Figure 3 shown, the lifting mechanism includes a stepping motor 4, a synchronous shaft 7 driven by the stepping motor 4 to rotate, and two lead screws 2. A bevel gear transmission or a worm and worm gear combination is used between the stepping motor 4 and the synchronous shaft 7; a bevel gear transmission is used between the synchronous shaft 7 and the lead screws 2, and a ball screw is formed between the lead screws 2 and the moving frame 9 by installing ball nuts.

[0030] The automatic limit detection device further includes a plurality of guide rods 3. Through holes matching the guide rods 3 are provided at the ends of the moving frame 9, and the ends of the moving frame 9 are slidably connected to the guide rods 3.

[0031] A moving marking needle 8 is slidably connected to the guide rod 3.

[0032] During operation, the water level sensor module converts the signal of the water level sensor 5 into a working instruction to drive the stepping motor 4. The driving force of the stepping motor 4 is transmitted to the lead screw 2 through the synchronous shaft 7. The rotation of the ball screw composed of the lead screw 2 is used to control the displacement of the moving frame 9. The sample to be measured is limited by the movable net racket 6 on the moving frame 9, so as to control the water level depth of the sample to be measured in the water tank 1 through the moving frame 9. The guide rod 3 is used to strengthen the stability of the moving frame 9 and is fixed in parallel to avoid the problem of insecure single-axis fixation when the lead screw 2 moves. At the same time, the guide rod 3 is also the carrier of the moving marking needle 8.

[0033] Embodiment 2

[0034] As Figure 2 shown, the movable net racket 6 includes a net-shaped net plate 61. The tail end of the net plate 61 is fixedly connected with a fixed shaft 62. The head end of the net plate 61 is provided with a lock catch 63. The tail end of the net plate 61 is hinged to the moving frame 9 through the fixed shaft 62, and the head end of the net plate 61 is connected to the moving frame 9 through the lock catch 63.

[0035] The net plate 61 is of a hollow structure, and the sample to be measured can be pre-fixed if necessary; the net plate 61 can be locked on the moving frame 9 through the lock catch 63 to overcome the buoyancy generated by the sample to be measured during the experiment and ensure the constancy of the net plate 61 during the experiment.

[0036] A water level scale 11 is slidably connected to the moving frame 9. The water level sensor 5 is fixed on the water level scale 11, and the lower end of the water level sensor 5 is aligned with the zero scale line of the water level scale 11.

[0037] The water level scale 11 is slidably connected to the moving frame 9, and the locking between the two can be tightened by a locking bolt; the horizontal section of the net plate 61 and the scale of the water level scale 11 are the water level control depths of the sample to be measured in the experiment, that is, the depth of the sample to be measured in the water in the water tank 1 is controlled by controlling this scale value. For the case where the expansion coefficient of the sample to be measured is relatively large, the sample to be measured can be pre-inflated. After confirming the highest water level in the water tank 1 after the sample to be measured expands, use the moving marking needle 8 on the guide rod 3 to mark on both sides of the water tank. The formed marking line is the zero line of the experimental water level. The relative experimental position of the water level scale 11 can be preset by using this zero line, avoiding continuous adjustment due to the expansion of the sample to be measured during the experiment, reducing unnecessary adjustment actions that have been predicted during the experiment, and improving the coherence of the test process and the efficiency of the experimental progress.

[0038] Embodiment 3

[0039] As Figure 4 、 5As shown, the water level sensor 5 includes a columnar sensor body 51. A “︺”-shaped current collecting end 511 is provided at the lower end of the sensor body 51. A hydrophobic line array is provided on the outer side wall of the sensor body 51. The hydrophobic line array is composed of a plurality of linear hydrophobic coatings 512 arranged along the height direction of the sensor body 51. The hydrophobic coatings 512 are arranged at equal intervals. An electrode one 52 is provided on one side of the current collecting end 511 at the lower part of the sensor body 51, and an electrode two 53 is provided on the other side of the current collecting end 511. A wave-proof ring 10 is further sleeved on the lower part of the sensor body 51. The electrode one 52, the electrode two 53 and the current collecting end 511 are all located inside the wave-proof ring 10.

[0040] The function of the wave-proof ring 10 is to shield the interference of the disturbance ripples generated on the water surface by the underwater sample to be measured during the inflation process to the water level sensor 5, ensure that the water surface around the water level sensor 5 is always in a static state, and avoid the intermittent interference caused by water ripples.

[0041] The working principle of the water level sensor 5 is the electrode method. Utilizing the conductivity of the medium water, when the electrode one 52 and the electrode two 53 contact the water surface, a circuit is formed and recognized by the water level sensor module. Then, a working signal is sent to the stepping motor 4 to move the movable net racket 6 upward. After the electrode one 52 and the electrode two 53 are separated from the water surface, the circuit is disconnected. After being recognized by the water level sensor module, the driving of the stepping motor 4 stops working, and the horizontal section of the movable net racket 6 is maintained at the expected position in the water.

[0042] The hydrophobic line array can accelerate the downward diversion of the liquid water invading the surface of the water level sensor 5 to the current collecting end 511. The special structure of the end cross-section of the current collecting end 511, combined with the fact that the end of the current collecting end 511 is lower than the cross-sections of the electrode one 52 and the electrode two 53, such a design is more conducive to the separation of the liquid that converges into drops, thus avoiding the short circuit between the electrodes caused by the runoff on the surface of the water level sensor 5 and sending a wrong signal to the water level sensor module.

[0043] In addition, it should be understood that those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. An automatic limit detection device, characterized in that: The invention comprises a water tank (1), a movable net rack (6) for limiting the position of a sample to be tested in the water tank (1), a mobile frame (9) for connecting the movable net rack (6), a lifting mechanism for driving the mobile frame (9) to move up and down, and a water level sensor module for controlling the lifting mechanism, wherein the water level sensor module comprises a water level sensor (5) mounted on the mobile frame (9).

2. An automatic limit detection device according to claim 1, characterized in that: The lifting mechanism comprises a stepping motor (4), a synchronous shaft (7) driven to rotate by the stepping motor (4), and two screw rods (2); a bevel gear transmission is adopted between the stepping motor (4) and the synchronous shaft (7) or a worm wheel and a worm gear cooperate to rotate; a bevel gear transmission is adopted between the synchronous shaft (7) and the screw rod (2); a ball screw is formed by installing a ball nut between the screw rod (2) and the moving frame (9).

3. The automatic limit detection device according to claim 1, characterized in that: It also comprises a plurality of guide rods (3), the ends of the movable frame (9) are provided with through holes matching the guide rods (3), and the ends of the movable frame (9) are slidably connected to the guide rods (3).

4. The automatic limit detection device according to claim 3, characterized in that: A movable marking needle (8) is slidably connected to the guide rod (3).

5. The automatic limit detection device according to claim 1, characterized in that: The movable net racket (6) comprises a mesh-shaped net plate (61), the rear end of the net plate (61) is fixedly connected to a fixed shaft (62), the front end of the net plate (61) is provided with a lock (63), the rear end of the net plate (61) is hinged to a movable frame (9) via the fixed shaft (62), and the front end of the net plate (61) is connected to the movable frame (9) via the lock (63).

6. The automatic limit detection device according to claim 1, characterized in that: A water level scale (11) is slidably connected to the movable frame (9), the water level sensor (5) is fixed on the water level scale (11), and the lower end of the water level sensor (5) is aligned with the zero point scale line of the water level scale (11).

7. The automatic limit detection device according to claim 1, characterized in that: The water level sensor (5) comprises a columnar sensor body (51), the lower end of the sensor body (51) is provided with a "︸"-shaped confluence end (511), the outer side wall of the sensor body (51) is provided with a hydrophobic line array, the hydrophobic line array is composed of a plurality of linear hydrophobic coatings (512) arranged along the height direction of the sensor body (51), and the hydrophobic coatings (512) are arranged at equal intervals; the lower part of the sensor body (51) is provided with an electrode 1 (52) located on one side of the confluence end (511) and an electrode 2 (53) located on the other side of the confluence end (511).

8. An automatic limit detection device according to claim 7, characterized in that: The lower part of the sensor body (51) is also sleeved with a wave-breaking ring (10), and the electrode 1 (52), the electrode 2 (53) and the confluence end (511) are all located inside the wave-breaking ring (10).

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