Pathological microtome based on air cushion assistance

Abstract

The invention discloses a pathological slicing machine based on air cushion assistance, relates to the technical field of slicing machines, and aims to solve the problem that when an ultrathin sample is cut, a cut slice is extremely easy to curl. According to the technical scheme, the device is characterized by comprising a rack; the clamping device is installed on the machine frame and comprises a sample frame support, a negative pressure cavity is formed in the sample frame support, a plurality of through holes communicated with the negative pressure cavity are formed in the surface of the sample frame support, and a negative pressure generator is communicated with the negative pressure cavity and used for generating and maintaining continuous negative pressure airflow; the slicing device comprises a knife rest and a blade; the air cushion anti-curling device is arranged on the rear side of the cutting edge of the blade and comprises an air cavity and a nozzle. A lifting force can be applied to the section through a uniform and stable laminar flow air cushion generated by the flow stabilizing mechanism and the flow guide lip, so that the cut pathological section can be flatly separated from a sample, the tissue section which is just cut can be uniformly supported, and the success rate and the flatness rate of the section are improved.

Description

Technical Field

[0001] This invention relates to the field of microtome technology, and more specifically, to a pathological microtome based on air cushion assistance. Background Technology

[0002] Pathological sectioning is a crucial step in histological and pathological diagnosis and research, and its quality directly affects the accuracy of subsequent observation and diagnosis. Paraffin-embedded tissue sections are one of the most commonly used techniques. Traditional pathological microtome machines mainly use mechanical sample feeding and blade cutting to prepare thin-layer sections from tissue blocks.

[0003] However, when cutting ultra-thin samples, due to the physical properties of paraffin and the friction between the microtome and the tissue block, the cut slices are very prone to curling, wrinkling, or even breaking. This curling phenomenon affects the integrity of the slices, and operators need to spend a lot of time and effort manually flattening the slices with a brush or pen. This is not only inefficient, but also very easy to damage the slices due to improper operation.

[0004] Therefore, a new solution is needed to address this problem. Summary of the Invention

[0005] In view of the shortcomings of the existing technology, the purpose of this invention is to provide a pathological slicer based on air cushion assistance, which has the advantage of improving the sample success rate.

[0006] The above-mentioned technical objective of the present invention is achieved through the following technical solution: a pathological slide machine based on air cushion assistance, comprising: frame; The clamping device, mounted on the frame, includes a sample holder with a negative pressure chamber inside. The sample holder has several through holes communicating with the negative pressure chamber on its surface. A negative pressure generator is connected to the negative pressure chamber to generate and maintain a continuous negative pressure airflow. The sample holder is made of a thermally conductive material and has an integrated semiconductor cooling chip inside to control the sample temperature. The through holes on the surface of the sample holder are non-uniformly distributed, with the density of through holes at the center being lower than that at the edge. A slicing device, comprising a blade holder and a blade; An air cushion anti-curling device is located on the rear side of the blade edge, including an air chamber and a nozzle. The nozzle is strip-shaped with a uniform slit width of 0.05-0.15mm to ensure uniform air output along the entire blade edge length. The air chamber is connected to the air inlet of the nozzle, and the air outlet of the nozzle is parallel to the blade surface. The air chamber is equipped with a flow stabilizing mechanism for converting the airflow from the air inlet into a stable static pressure flow. The flow stabilizing mechanism includes a pressure stabilizing chamber and a flow equalization plate. The pressure stabilizing chamber is located inside the air chamber and is positioned near the air inlet side of the nozzle. The cross-sectional area of ​​the pressure stabilizing chamber is larger than the cross-sectional area of ​​the air outlet of the nozzle. The flow equalization plate has several mesh holes and is fixedly connected inside the pressure stabilizing chamber.

[0007] The present invention is further configured such that: the clamping device further includes clamping plates disposed on both sides of the sample holder, the clamping plates being slidably connected to the surface of the sample holder by bolts.

[0008] The present invention is further configured such that: a constant temperature water bath is provided on the frame, and the inlet of the constant temperature water bath faces the side of the blade.

[0009] The invention is further configured to include a guide lip, which is disposed on the upper and lower sides of the nozzle near its outlet. The inner surface roughness Ra of the guide lip is not greater than 0.8 micrometers, and its outline is a smooth tapering curve, used to smoothly accelerate and guide the rectified airflow to the outlet of the nozzle.

[0010] The present invention is further configured such that: at least two parallel flow equalization plates are provided in the pressure stabilizing cavity, and the mesh aperture of each flow equalization plate decreases sequentially along the airflow direction.

[0011] The present invention is further configured such that the mesh on the flow equalization plate is a tapered hole, and the diameter of the inlet end hole is larger than the diameter of the outlet end hole.

[0012] The present invention is further configured such that: the negative pressure generator includes a vacuum pump, a negative pressure regulating valve and a pressure sensor, the pressure sensor is used to monitor the pressure value in the negative pressure chamber in real time, and the suction port of the vacuum pump is connected to the bottom of the sample holder.

[0013] The present invention is further configured such that the guide lip is made of stainless steel or hard anodized aluminum alloy.

[0014] In summary, the present invention has the following beneficial effects: The uniform and stable laminar air cushion generated by the flow stabilizing mechanism and the flow guide lip can apply a lifting force to the slide, ensuring that the cut pathological slide can be separated from the sample flatly. It can evenly support the freshly cut tissue slide, improving the success rate and flatness of the slide. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of the present invention. Figure 1 ; Figure 2 This is a schematic diagram of the structure of the present invention. Figure 2 ; Figure 3 This is a cross-sectional view of the present invention; Figure 4 for Figure 3 Enlarged view of point A in the image; Figure 5 for Figure 3 Enlarged view of point B in the image.

[0016] In the diagram: 1. Frame; 2. Sample holder; 3. Negative pressure chamber; 4. Through hole; 5. Knife holder; 6. Blade; 7. Gas chamber; 8. Nozzle; 9. Pressure stabilizing chamber; 10. Flow equalization plate; 11. Mesh; 12. Guide lip; 13. Clamping plate; 14. Constant temperature water bath; 15. Semiconductor cooling chip; 16. Vacuum pump; 17. Negative pressure regulating valve. Detailed Implementation

[0017] To enable those skilled in the art to better understand the technical solutions of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of this application can be combined with each other.

[0018] In the description of this invention, it should be noted that the terms "upper", "lower", "inner", "outer", "top / bottom", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention 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. Therefore, they should not be construed as limiting this invention.

[0019] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installed," "equipped with," "sleeved / connected," "connected," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or a bulk connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0020] A pathological microtome based on air cushion assistance, such as Figures 1-5As shown, the device includes a frame 1, a clamping device, a slicing device, and an air cushion anti-curling device. The frame 1 serves as the overall support structure and is made of rigid materials such as aluminum alloy to ensure stable installation of all components. The clamping device is mounted on the frame 1 and is used to fix the sample. Generally, the sample is a paraffin-embedded pathological tissue block. The sample holder 2 is used to hold the sample. The sample holder 2 has a negative pressure chamber 3 inside, and a negative pressure generator is connected to the negative pressure chamber 3 to generate and maintain a continuous negative pressure airflow. Generally, thin samples can be directly processed using the airflow inside the negative pressure chamber 3. The generated negative pressure effect adheres to the sample holder 2. The negative pressure generator includes a vacuum pump 16, a negative pressure regulating valve 17, and a pressure sensor. The pressure sensor is used to monitor the pressure value in the negative pressure chamber 3 in real time. The suction port of the vacuum pump 16 is connected to the bottom of the sample holder 2. For most thin tissue samples, this strong adsorption force can make them adhere firmly and flatly to the surface of the sample holder 2, effectively preventing the samples from loosening, shifting, or deforming during high-speed slicing, thus laying a solid foundation for obtaining high-quality thin-layer sections.

[0021] The negative pressure generator is not simply a vacuum generator, but a closed-loop controller with real-time monitoring and feedback. Its core components include a vacuum pump 16 that provides power, a negative pressure regulating valve 17 that finely adjusts the adsorption force, and a pressure sensor that monitors the pressure value inside the negative pressure chamber 3 in real time. The suction port of the vacuum pump 16 is directly connected to the bottom of the sample holder 2, efficiently drawing air from the negative pressure chamber 3 to establish negative pressure. The pressure sensor feeds back the monitored real-time pressure data to the negative pressure generator, which then dynamically controls the pumping efficiency of the vacuum pump 16 through the negative pressure regulating valve 17, thereby stabilizing the pressure value inside the negative pressure chamber 3 within a preset ideal range. For samples of different sizes, textures, or embedding conditions, operators can set different negative pressure values ​​to ensure that fragile samples are not damaged by excessive adsorption while ensuring that tough samples are firmly fixed. This precise management of adsorption force is a prerequisite for achieving high-quality, non-destructive slides.

[0022] In one embodiment, the clamping device is mounted on the frame 1 and includes a sample holder 2. The sample holder 2 has several through holes 4 communicating with the negative pressure chamber 3 on its surface. The sample holder 2 is positioned on the sliding guide rail of the pathology slider to ensure stable and precise up-and-down movement during the slicing process. When the negative pressure generator is activated, a continuous negative pressure is generated within the negative pressure chamber 3. This strong adsorption force, through the through holes 4 distributed throughout the surface, can evenly adsorb most thin, flat paraffin-embedded tissue samples onto the surface of the sample holder 2. This fixation method provides comprehensive adsorption force, effectively preventing minute displacement, jumping, or deformation of the sample under the high-speed, sharp blade 6 cutting, thus laying a solid foundation for obtaining continuous, flat, and uniformly thick slices.

[0023] Furthermore, the clamping device also includes clamping plates 13 disposed on both sides of the sample holder 2. The clamping plates 13 are slidably connected to the surface of the sample holder 2 by bolts. When dealing with samples that are large in volume, irregular in shape, or particularly fragile in texture, and whose stability may not be guaranteed by negative pressure adsorption alone, the bolts can be tightened to allow the two clamping plates 13 to be smoothly clamped from the left and right sides of the sample. This mechanical clamping method provides a strong lateral constraint force, which perfectly complements the vertical adsorption force of the sample generated by negative pressure adsorption, forming a three-dimensional, double-protection fixing method.

[0024] In one embodiment, the slicing device includes a blade holder 5 and a blade 6. The blade holder 5 provides a firm clamp for the blade 6, ensuring that it does not experience minor displacement or vibration when subjected to cutting stress. It also integrates a blade advance / retreat mechanism with an angle adjustment mechanism, allowing the operator to fine-tune the entry angle and tilt angle of the blade 6 relative to the sample to achieve the best cutting effect. An air cushion anti-curling device is located on the rear side of the blade edge of the blade 6, including an air chamber 7 and a nozzle 8. The nozzle 8 is strip-shaped with a uniform slit width of 0.05-0.15 mm to ensure uniform air output along the entire length of the blade edge. The air chamber 7 is connected to the air inlet of the nozzle 8, and the air outlet of the nozzle 8 is parallel to the blade surface of the blade 6. This ensures that when compressed air is ejected from this narrow nozzle 8, it can form a continuous, stable, and uniform airflow curtain along the entire working surface of the same length as the blade edge of the blade 6, effectively supporting the slice and preventing it from curling locally.

[0025] The air chamber 7 is equipped with a flow stabilizing mechanism to convert the airflow from the inlet into a stable static pressure flow. The inlet of the air chamber 7 is connected to an external air blower via a duct. The air blown out by the air blower is purified before entering the air chamber 7. The flow stabilizing mechanism includes a pressure stabilizing chamber 9 and a flow equalizing plate 10. The pressure stabilizing chamber 9 is located inside the air chamber 7 and is positioned near the inlet of the nozzle 8. The cross-sectional area of ​​the pressure stabilizing chamber 9 is larger than the cross-sectional area of ​​the outlet of the nozzle 8. The flow equalizing plate 10 has several mesh holes 11 and is fixedly connected to the pressure stabilizing chamber 7. Inside the pressure chamber 9, at least two parallel flow equalization plates 10 are arranged. The aperture of the mesh 11 on each flow equalization plate 10 decreases sequentially along the airflow direction. The mesh 11 on the flow equalization plate 10 is a conical hole, with the inlet diameter larger than the outlet diameter. The inlet of the air chamber 7 is relatively spacious. Then, the airflow enters the pressure equalization chamber 9, where it is initially stabilized. According to the basic principles of fluid mechanics, when airflow enters a narrow channel from a wide channel, the velocity in the wide channel will decrease significantly, and its dynamic pressure will be converted into static pressure. This increased static pressure area means that the air pressure becomes more uniform and stable, effectively buffering and absorbing pressure fluctuations and turbulence from the upstream air source. Next, the airflow enters the flow equalization plate 10. The flow equalization plate 10 avoids being covered with a sieve-like structure of dense mesh 11, separating and sorting the large airflow streams to form a large number of fine streams, further eliminating internal eddies and velocity differences.

[0026] Furthermore, the aperture of the mesh 11 of each flow equalizer 10 is set to decrease sequentially along the direction of airflow. When the airflow passes through the relatively large aperture of the first layer of mesh 11, the larger vortices inside are initially dispersed. Then, the airflow enters the second layer of mesh 11 with smaller aperture, and the finer turbulent structure is further eliminated. This cascaded design with decreasing aperture ensures that the airflow is gradually stabilized. Finally, before reaching the nozzle 8, the energy distribution inside is fully homogenized, and the velocity difference is minimized. Moreover, each mesh 11 on the flow equalizer 10 is processed such that the aperture at the air inlet is larger than the aperture at the air outlet. When the airflow enters from the larger inlet and is forced out from the smaller outlet, it will undergo a smooth acceleration process inside the hole. This can effectively prevent the airflow from separating on the hole wall and generating new vortices, thus ensuring the adhesion and stability of the flow.

[0027] In one embodiment, a guide lip 12 is also included. The guide lip 12 is made of stainless steel or hard anodized aluminum alloy, possessing extremely high hardness, excellent wear resistance, and dimensional stability, effectively resisting wear. The guide lip 12 is disposed on the upper and lower sides of the nozzle 8 near its outlet. The inner surface roughness Ra value of the guide lip 12 is no greater than 0.8 micrometers, and its profile is a smooth, tapering curve. This is used to smoothly accelerate and guide the rectified airflow to the outlet of the nozzle 8. This roughness reduces the frictional resistance between the airflow and the wall surface, allowing the airflow to adhere tightly to the profile of the guide lip 12. The smooth, tapering curve of the guide lip 12's profile simulates some characteristics of a high-efficiency Laval nozzle. When the airflow, after being fully rectified by the front flow stabilizing mechanism and with stable pressure, enters this tapering channel, according to Bernoulli's principle, as the cross-sectional area of ​​the flow channel steadily decreases, the static pressure of the airflow will gradually be converted into dynamic pressure, thereby achieving a controllable and uniform acceleration process. The airflow velocity is controlled between 0.5 and 2.0. Within the range of m / s, this ensures that when the airflow leaves the outlet, it not only meets the required speed, but more importantly, it forms a laminar air curtain with uniform thickness, stable pressure, and consistent direction, which can evenly support the freshly cut tissue slices and provide them with comprehensive and gentle support.

[0028] In one embodiment, a constant temperature water bath 14 is provided on the frame 1, with the feed port of the constant temperature water bath 14 facing the side of the blade 6. On the frame 1 of the pathology slide machine, a constant temperature water bath 14 is provided behind the blade 6 after it has completed the cutting action. The moment the blade 6 separates the extremely thin paraffin tissue section from the sample, it is lifted by the airflow generated by the nozzle 8, thus quickly separating it from the blade 6. The tissue section is generally a continuous sheet structure. The lifted tissue section can move along the blade 6 towards the constant temperature water bath 14 and is guided to the liquid surface of the constant temperature water bath 14. The constant temperature water bath 14 maintains the deionized water or special developing solution at a constant and suitable temperature through its internal temperature control system. The section floats on the warm liquid surface, and the paraffin it carries will slightly soften due to the heat. At the same time, the surface tension of the water will gently and evenly act on the entire lower surface of the section, effectively smoothing out any tiny wrinkles or curls that may have occurred during the cutting and transport process. Then it can be picked up and transferred to a glass slide, providing a uniform sample for subsequent staining and pathological diagnosis.

[0029] In one embodiment, the sample holder 2 is made of a thermally conductive material, such as aluminum alloy or copper alloy, which ensures rapid and uniform energy conduction within the sample holder 2. The sample holder 2 also integrates a semiconductor cooling chip 15 for controlling sample temperature. The semiconductor cooling chip 15 has bidirectional temperature control capability; by changing the direction of the direct current, it can switch between cooling and heating modes. Based on the ambient temperature and sample characteristics, the semiconductor cooling chip 15 can pre-cool or preheat the sample to achieve optimal cutting hardness. Simultaneously, during the slicing process, the sample temperature is monitored in real time. When the ambient temperature is high or heat is generated due to the high-speed cutting friction of the blade 6, the sample temperature may rise, causing the paraffin to soften or the tissue toughness to decrease, thereby increasing the risk of slice adhesion or tearing. In this case, the semiconductor cooling chip 15 can activate the cooling mode to quickly cool the sample through the sample holder 2, maintaining the hardness of the paraffin and the rigidity of the tissue, ensuring smooth cutting. Conversely, in cold environments, it can be appropriately heated to prevent excessive embrittlement of the paraffin, improving the applicability of the pathology slide machine in various environments.

[0030] In one embodiment, the through holes 4 on the surface of the sample holder 2 are not uniformly distributed, with the density of through holes 4 at the center being lower than that at the edge. When negative pressure is established, the adsorption force acts on the lower surface of the sample through the through holes 4. If the through holes 4 are uniformly distributed, the strong negative pressure generated below the central region of the sample may cause excessive concentrated stress on the soft or fragile tissue sample center, which can easily damage the tissue sample. Similarly, the area around the tissue sample is most likely to lose its adsorption seal due to air leakage. By reducing the density of through holes 4 in the central region, the adsorption force in the central region is dispersed, avoiding excessive stress concentration and thus protecting the integrity of the sample.

[0031] The usage method is as follows: First, the operator clamps the paraffin-embedded tissue sample according to its size and characteristics, placing the sample on the sample holder 2. The negative pressure generator is then activated, using uniform negative pressure adsorption to initially fix the sample. For large or irregular samples, the clamping plates 13 on both sides can be slid and locked to apply lateral clamping force, forming a dual fixation effect of negative pressure and mechanical force. Simultaneously, depending on the ambient temperature and sample characteristics, the sample can be pre-cooled or pre-heated using a semiconductor cooling chip 15 integrated within the sample holder 2 to achieve optimal cutting hardness. Subsequently, the sectioning parameters are set, and the pathology procedure is initiated. At the moment the blade 6 cuts, the air cushion anti-curling device behind it is activated simultaneously. The uniform laminar flow, rectified and accelerated by the pressure stabilizing chamber 9, the flow equalizing plate 10 and the guide lip 12, is ejected from the nozzle 8, forming a stable air cushion parallel to the blade surface. This air cushion immediately supports and guides the cut slice, effectively preventing it from curling. Finally, the slice, which is smoothly transported by the air cushion, floats onto the liquid surface of the constant temperature water bath 14. Under the action of suitable temperature and surface tension of water, the tiny wrinkles on the slice are completely flattened, making it easier to retrieve with a glass slide for subsequent staining and observation.

[0032] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A pathological microtome based on air cushion assistance, characterized in that, include: frame; The clamping device, mounted on the frame, includes a sample holder with a negative pressure chamber inside. The sample holder has several through holes communicating with the negative pressure chamber on its surface. A negative pressure generator is connected to the negative pressure chamber to generate and maintain a continuous negative pressure airflow. The sample holder is made of a thermally conductive material and has an integrated semiconductor cooling chip inside to control the sample temperature. The through holes on the surface of the sample holder are non-uniformly distributed, with the density of through holes at the center being lower than that at the edge. A slicing device, comprising a blade holder and a blade; An air cushion anti-curling device is located on the rear side of the blade edge, including an air chamber and a nozzle. The nozzle is strip-shaped with a uniform slit width of 0.05-0.15mm to ensure uniform air output along the entire blade edge length. The air chamber is connected to the air inlet of the nozzle, and the air outlet of the nozzle is parallel to the blade surface. The air chamber is equipped with a flow stabilizing mechanism for converting the airflow from the air inlet into a stable static pressure flow. The flow stabilizing mechanism includes a pressure stabilizing chamber and a flow equalization plate. The pressure stabilizing chamber is located inside the air chamber and is positioned near the air inlet side of the nozzle. The cross-sectional area of ​​the pressure stabilizing chamber is larger than the cross-sectional area of ​​the air outlet of the nozzle. The flow equalization plate has several mesh holes and is fixedly connected inside the pressure stabilizing chamber.

2. A pathological slicer based on air cushion assistance according to claim 1, characterized in that: The clamping device also includes clamping plates disposed on both sides of the sample holder, the clamping plates being slidably connected to the surface of the sample holder by bolts.

3. A pathological slicer based on air cushion assistance according to claim 1, characterized in that: The frame is equipped with a constant temperature water bath, and the inlet of the constant temperature water bath faces the blade side.

4. A pathological slicer based on air cushion assistance according to claim 1, characterized in that: It also includes a guide lip, which is disposed on the upper and lower sides of the nozzle near its outlet. The inner surface roughness Ra value of the guide lip is no greater than 0.8 micrometers, and its outline is a smooth tapering curve, which is used to smoothly accelerate and guide the rectified airflow to the outlet of the nozzle.

5. A pathological slicer based on air cushion assistance according to claim 1, characterized in that: The pressure stabilizing chamber is provided with at least two parallel flow equalization plates, and the mesh aperture of each flow equalization plate decreases sequentially along the airflow direction.

6. A pathological slicer based on air cushion assistance according to claim 5, characterized in that: The mesh on the flow equalization plate is tapered, with the inlet diameter being larger than the outlet diameter.

7. A pathological slicer based on air cushion assistance according to claim 1, characterized in that: The negative pressure generator includes a vacuum pump, a negative pressure regulating valve, and a pressure sensor. The pressure sensor is used to monitor the pressure value inside the negative pressure chamber in real time, and the suction port of the vacuum pump is connected to the bottom of the sample holder.

8. A pathological slicer based on air cushion assistance according to claim 4, characterized in that: The guide lip is made of stainless steel or hard anodized aluminum alloy.

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