A transformer oil batch automatic quantitative sample dispensing device and a sample feeding method

Abstract

The application provides a transformer oil batch automatic quantitative sample distribution device and a sample feeding method. The device comprises a sample placing support arranged at a base. A sampling component comprising a plurality of sampling units is arranged at the sample placing support. The sampling unit comprises, from top to bottom, a micro-elastic positive pressure component, a syringe component and an adapter component. The adapter component comprises a sampling needle rod. An oil inlet nozzle is communicated with a converging pipe of the distribution device through an oil inlet electromagnetic valve. When the distribution device works, the micro-elastic positive pressure component applies pressure to the top of the syringe body of the syringe component to make the syringe body in a micro-positive pressure state. The sampling needle rod is inserted into the bottom of the syringe body, so that the sample in the syringe body can flow out to the oil inlet nozzle through the sampling needle rod. The distribution device extracts the sample in different sampling units through the converging pipe by selecting the oil inlet electromagnetic valves of different oil inlet nozzles to be turned on. The application can ensure multiple sample feeding, avoid the problem of mutual interference of multiple samples, and achieve the purposes of micro-positive pressure storage of the sample and quantitative feeding of the sample.

Description

Technical Field

[0001] This invention relates to the field of measuring equipment technology, and in particular to an automatic quantitative sample dispensing device and injection method for transformer oil in batches. Background Technology

[0002] Transformer oil plays a vital role, serving not only for electrical insulation but also for cooling, arc extinguishing, and corrosion prevention. Therefore, regular analysis and monitoring of transformer oil provides crucial information about the transformer's health status and potential faults. The "Preventive Testing Regulations for Power Equipment" details the test items and cycles for transformer oil, requiring regular analysis of parameters including chromatographic analysis, trace moisture detection, acid value detection, withstand voltage testing, and dielectric loss testing. Transformer oil sample analysis involves multiple steps, including sampling, pretreatment, quantification, and analysis. Currently, most transformer oil sample analyses involve independent analysis of each parameter. Most equipment requires manual sample injection, hindering automated analysis.

[0003] The "Sampling Method for Power Generation Oils (Transformer Oil, Turbine Oil)" stipulates that the determination of water content and analysis of dissolved gases in oil require sampling using a syringe. A 100mL glass syringe is generally used. After the sample is collected from the field and brought to the laboratory, it needs to be quantified before being injected into the analytical equipment for analysis.

[0004] 2.1 During chromatographic analysis, excess sample is manually dispensed according to the syringe markings. This method processes one sample at a time, requiring manual reading to determine the sample volume. The accuracy of syringe markings varies significantly between different batches and manufacturers, leading to substantial variability in transformer oil chromatographic analysis data.

[0005] 2.2 Existing devices also utilize robotic arms in conjunction with syringes to achieve chromatographic analysis of samples. This type of equipment can automate the chromatographic analysis of transformer oil, but it suffers from complex structure, high equipment cost, and limited analytical capabilities. (CN 109765323 A, CN110243975B, CN105424846 A)

[0006] 2.3 Some devices also use diaphragm pumps or plunger pumps to quantify and inject samples. During the sample transfer process, the concentration of characteristic gases in the sample may change.

[0007] This invention proposes an apparatus and method for automatic quantitative distribution of transformer oil batch samples, relating to the field of automatic detection and analysis of transformer oil. This apparatus solves the following technical problems in traditional technologies:

[0008] 1. Most existing testing devices are manual analysis equipment, generally lacking automatic sample sequence analysis functions, and can only test one sample at a time, thus failing to achieve the purpose of multi-sample testing.

[0009] 2. Most devices that can perform multi-sample testing use robotic arms and syringes to dispense samples, resulting in complex overall structures, large equipment size, and high costs.

[0010] 3. Existing testing devices generally do not have separate sealing and protection measures for the samples to be tested. During the sample transfer process, the use of pumps or other methods can easily create negative pressure, causing characteristic gases in the transformer to escape, or poor needle sealing can cause negative pressure to seep in air, affecting the accuracy of the insulating oil chromatographic analysis results and the test results. Summary of the Invention

[0011] This invention proposes an automatic quantitative sample distribution device and injection method for transformer oil in batches, which can ensure the injection of multiple samples, avoid the problem of mutual interference between multiple samples, and simultaneously achieve the purpose of micro-positive pressure storage of samples and quantitative injection of samples.

[0012] The present invention adopts the following technical solution.

[0013] An automatic quantitative sample dispensing device for transformer oil in batches, the dispensing device includes a sample placement bracket (2) located at a base (1); the sample placement bracket is provided with a sampling component (3) containing multiple sampling units; the sampling unit includes a positive pressure part (33), a syringe component (31), and an adapter component (32) arranged from top to bottom.

[0014] The sample dispensing end of the dispensing device is connected to an external device. The syringe component is a syringe array consisting of multiple syringe bodies arranged in rows and columns for storing samples. The adapter component is an adapter array consisting of multiple adapters below the syringe array that are connected to the sample dispensing end. Each syringe body corresponds to each adapter. When the dispensing device is working, the positive pressure part is connected to the top of the syringe body with its elastic element. By applying pressure, the sharp input end of the adapter component penetrates the elastic sealing cap at the bottom of the syringe body. When the oil inlet of a certain adapter is connected to the sample dispensing end, the sample in the syringe body corresponding to that adapter flows out through the sample dispensing end.

[0015] When the sharp input end of the adapter component disengages from the sealing cap, the sealing cap retracts with its elasticity and seals the bottom of the syringe body.

[0016] The adapter component includes a sampling rod (325) of a sampling needle (34); the tip of the sampling needle points to the bottom of the syringe body, and the needle tail is connected to the oil inlet (3211) of the adapter component; the oil inlet is connected to the manifold (8) of the distribution device via an oil inlet solenoid valve (322); when the distribution device is working, the positive pressure part applies pressure to the top of the syringe body (311) of the syringe component to make it in a positive pressure state; the sampling needle pierces the bottom of the syringe body, so that the sample in the syringe body can flow out to the oil inlet through the sampling needle; the distribution device extracts samples from different sampling units through the manifold by selecting and opening the oil inlet solenoid valves at different oil inlets.

[0017] The adapter component is fixed on the base, and the syringe component is inserted into the adapter component to form a clearance fit. The base is provided with a vertical guide rail bracket (4). The positive pressure part is driven by the driving device (5) to move vertically along the guide rail bracket. When it moves downward to the syringe component, it contacts the top of the syringe body.

[0018] The positive pressure part is a micro-elastic positive pressure component including a top pressure spring. When sampling, when the positive pressure part descends, its top pressure spring (332) moves downward to press the syringe body (311) to generate positive pressure inside, so as to prevent external air from entering, and to make the plunger of the syringe body press the sample inside to be discharged under the pressure of the top pressure spring, so as to avoid manual pushing of the tube.

[0019] When sampling is complete and the syringe component needs to be replaced, the stepper motor drives the lead screw nut to move the positive pressure part upward away from the syringe component, so that the syringe body of the syringe component can be removed and replaced.

[0020] The driving device includes a stepper motor, a ball screw, a screw nut, a connecting plate, a slide rail, and a slider; wherein the slide rail is installed at the guide rail bracket, one side of the slider is slidably connected to the slide rail, the other side of the slider and the connecting plate are fixed on the outer shell of the positive pressure part, and the connecting plate is also connected to the screw nut, so that the positive pressure part (33) moves up and down through the screw nut transmission.

[0021] When sampling, the positive pressure part moves downward to the syringe component and contacts the top of the syringe body. The outer shell of the positive pressure part presses the upper pressure cylinder (334) of the positive pressure part to continue moving downward, compressing the top pressure spring (332) of the guide groove (333). The elastic force of the compressed top pressure spring is applied to the top of the syringe body through the lower pressure cylinder (331) of the positive pressure part.

[0022] The sampling needle is inserted into the oil inlet in the middle of the adapter body (321) of the adapter component; the lower part of the sampling rod is connected to the sampling spring (324) placed in the sampling positioning seat (323) of the adapter component, and the top of the sampling positioning seat is threadedly connected to the sampling cap (326); the sampling rod is inserted through the sampling cap, and when the sampling rod is pressed down, the spring force of the sampling spring buffers and absorbs the shock.

[0023] The positioning seat is placed inside the adapter body and is coaxial with it. The sampling needle passes through the sampling spring and extends into the center hole of the sampling rod.

[0024] The output end of the syringe body is fitted with a replaceable sealing cap (312). When the syringe body, together with the sealing cap, passes through the circular through hole on the sample holder and is inserted into the center hole of the sampling rod, the tip of the sampling needle pierces the sealing cap. At this time, the liquid sample in the syringe body enters the oil inlet along the sampling needle. The other end of the oil inlet is connected to the inlet of the oil inlet solenoid valve.

[0025] The outlet of the oil inlet solenoid valve (322) is connected to one end of the oil outlet pipe (3212) of the adapter component, and the other end of the oil outlet pipe extends into the manifold box (7) through the manifold (8).

[0026] The oil inlet solenoid valve is a normally closed solenoid valve. When it is energized, its inlet and outlet are connected, allowing the sample in the syringe body located above the oil inlet solenoid valve to flow through the manifold to the manifold box under the action of the positive pressure spring. The sample in the manifold box is then exported to external equipment through the output port of the manifold box.

[0027] The manifold is composed of several pipes connected together, wherein a quick-connect pipe purging connector (81) is provided at the initial end of the pipes; an inclined box partition is provided inside the manifold box, and a quick-connect box purging connector (82) is connected to the higher end of the box partition. A quick-connect sample outlet is provided at the lower end of the box partition for sample outlet from the manifold box.

[0028] A sampling method for an automatic quantitative batch sample dispensing device for transformer oil, the aforementioned automatic quantitative batch sample dispensing device for transformer oil, is characterized by comprising the following steps;

[0029] Step S1: After drawing the transformer oil to be tested into the syringe body, seal it with a sealing cap;

[0030] Step S2: Insert one end of the sealing cap of the syringe into the center hole of the sampling rod. At this time, the sampling needle will pierce the sealing cap.

[0031] Step S3: The stepper motor is powered on, and the positive pressure part is pressed down under the action of the lead screw nut. At this time, the top pressure spring presses the main body of each syringe and contracts, so that positive pressure is generated inside each syringe.

[0032] Step S4: Select the sample to be tested. At this time, the corresponding oil inlet solenoid valve is energized. The sample inside the corresponding syringe is led out through the manifold to the manifold box under the action of the top pressure spring. Then, it is sent to the corresponding detection device through the flow sensor at the output end of the manifold box. After the flow reaches the set value, the corresponding oil inlet solenoid valve is de-energized.

[0033] Step S5: Introduce carrier gas and blank oil through the pipeline purging quick connector and the box purging quick connector to purge the manifold and manifold box. After cleaning, proceed with the next sample injection.

[0034] In step S3, the amount of contraction deformation generated by each top pressure spring pressing the syringe body can push out all the samples in the corresponding syringe body when it is extended and released.

[0035] This invention relates to an automatic batch quantitative sample dispensing device and injection method for transformer oil. The device can simultaneously accommodate multiple samples while maintaining a slight positive pressure on each. Combined with a quick-connect sample connector, sample dispensing switch, purging mechanism, and quantitative device, it enables separate quantitative injection of multiple samples while preventing cross-interference. The patent also provides an injection method that, in conjunction with the device, avoids sample cross-interference. This invention utilizes a spring-loaded needle device to maintain a slight positive pressure throughout the sample storage and transfer process. This device integrates quick-connect sample connectors, sample storage, sample dispensing switch, purging and cleaning, and quantitative sample injection functions into a novel sample dispensing and injection system. This system ensures multiple sample injections while avoiding mutual interference, achieving both positive pressure sample storage and quantitative sample injection.

[0036] This invention enables precise quantification and transfer of samples under positive pressure, and, in conjunction with automated analysis equipment, enables automated analysis of batch samples. In this invention, the sample switching device uses a miniature solenoid valve as the switching device, and a reliable purging process is designed in the common pipeline, thereby avoiding cross-interference in the batch analysis of different samples.

[0037] This invention can be used for the chromatographic detection of transformer oil. When used in conjunction with a portable insulating oil chromatograph, the downstream equipment of this invention can be used as an automated transformer oil analysis device, providing expanded batch sample processing capabilities for portable, fully automated chromatography. This achieves automated analysis of batch samples.

[0038] This invention enables automated batch multi-parameter analysis of insulating oil samples and avoids the traditional sampling method that uses complex motion mechanisms such as robotic arms, thus offering a cost advantage. This device integrates functions such as quick sample connection connectors, sample storage, sample distribution and switching, purging and cleaning, and sample quantification, forming a new sample distribution and injection device. This ensures the injection of multiple samples while avoiding the problem of mutual interference between multiple samples, and simultaneously achieves the purpose of positive pressure sample storage and quantitative sample injection.

[0039] The advantages of this invention are:

[0040] (1) The present invention designs a syringe batch sample dispensing device based on spring as driving force. It can automatically dispense multiple samples at one time.

[0041] (2) In this invention, a micro-positive pressure pusher device is used to maintain a micro-positive pressure throughout the sample preservation and transfer process. Automatic micro-positive pressure output of the sample can be achieved without the need for a tubular pump. At the same time, this micro-positive pressure can also achieve the purpose of positive pressure storage of the sample to prevent external air from entering.

[0042] (3) In order to be compatible with existing ordinary 100mL syringes, a syringe adapter was designed, which, together with a micro solenoid valve, achieved a reliable seal during the sample analysis process.

[0043] (4) The functions of sample collection, purging and cleaning are integrated into one, which can achieve multiple sample collection while avoiding cross-contamination of samples, and has a cost advantage.

[0044] (5) This device is automatically programmed and controlled, and with the help of spring force and micro flow sensor, it can meet the precision injection volume requirements of different types of tests and has strong versatility. Attached Figure Description

[0045] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments:

[0046] Appendix Figure 1 This is a three-dimensional schematic diagram of the present invention;

[0047] Appendix Figure 2 This is a planar schematic diagram of the sampling component;

[0048] Appendix Figure 3 This is an exploded schematic diagram of the sampling component;

[0049] Appendix Figure 4 This is a partial sectional three-dimensional schematic diagram of the adapter body;

[0050] Appendix Figure 5 This is a cross-sectional view of the sampling needle piercing the syringe component;

[0051] Appendix Figure 6 This is a three-dimensional schematic diagram of the positive pressure section;

[0052] Appendix Figure 7 This is a schematic diagram showing the connection between the manifold and the manifold box;

[0053] Appendix Figure 8 This is a schematic diagram of the control principle of the present invention;

[0054] Appendix Figure 9 This is a schematic diagram of the pipeline connection of the present invention;

[0055] In the diagram: 1-Base; 2-Sample placement bracket; 3-Sampling component; 4-Guide rail bracket; 5-Drive device; 6-Electrical control box; 7-Combiner box; 8-Combiner pipe;

[0056] 31-Injector component; 32-Adapter component; 81-Purge quick connector for pipeline; 82-Purge quick connector for housing;

[0057] 324 - Sampling spring; 325 - Sampling rod; 326 - Sampling cap; 33 - Positive pressure part; 331 - Lower pressure cylinder; 332 - Top pressure spring; 333 - Guide groove; 334 - Upper pressure cylinder; 34 - Sampling needle;

[0058] 311-Injector body; 312-Sealing cap; 321-Adapter body; 322-Inlet solenoid valve; 323-Sampling positioning seat;

[0059] 3211 - Adapter inlet nozzle; 3212 - Adapter outlet pipe; 3213 - Solenoid valve threaded hole. Detailed Implementation

[0060] like Figure 1 As shown, an automatic quantitative sample dispensing device for transformer oil in batches includes a sample placement bracket 2 located at a base 1; a sampling component 3 containing multiple sampling units is provided at the sample placement bracket; the sampling unit includes a positive pressure part 33, a syringe component 31, and an adapter component 32 arranged from top to bottom.

[0061] The sample dispensing end of the dispensing device is connected to an external device. The syringe component is a syringe array consisting of multiple syringe bodies arranged in rows and columns for storing samples. The adapter component is an adapter array consisting of multiple adapters below the syringe array that are connected to the sample dispensing end. Each syringe body corresponds to each adapter. When the dispensing device is working, the positive pressure part is connected to the top of the syringe body with its elastic element. By applying pressure, the sharp input end of the adapter component penetrates the elastic sealing cap at the bottom of the syringe body. When the oil inlet of a certain adapter is connected to the sample dispensing end, the sample in the syringe body corresponding to that adapter flows out through the sample dispensing end.

[0062] When the sharp input end of the adapter component disengages from the sealing cap, the sealing cap retracts with its elasticity and seals the bottom of the syringe body.

[0063] The adapter component includes a sampling rod 325 of a sampling needle 34; the tip of the sampling needle points to the bottom of the syringe body, and the tail of the needle communicates with the oil inlet 3211 of the adapter component; the oil inlet communicates with the manifold 8 of the distribution device via an oil inlet solenoid valve 322; when the distribution device is working, the positive pressure part applies pressure to the top of the syringe body 311 of the syringe component to make it in a positive pressure state; the sampling needle pierces the bottom of the syringe body, so that the sample in the syringe body can flow out to the oil inlet through the sampling needle; the distribution device extracts samples from different sampling units through the manifold by selecting and opening the oil inlet solenoid valves at different oil inlets.

[0064] The adapter component is fixed on the base, and the syringe component is inserted into the adapter component to form a clearance fit. The base is provided with a vertical guide rail bracket 4. The positive pressure part is driven by the driving device 5 to move vertically along the guide rail bracket. When it moves downward to the syringe component, it contacts the top of the syringe body.

[0065] The positive pressure part is a micro-elastic positive pressure component including a top pressure spring. When sampling, when the positive pressure part descends, its top pressure spring 332 moves downward to press the syringe body 311 to generate positive pressure inside, so as to prevent external air from entering, and to make the plunger of the syringe body press the sample inside to be discharged under the pressure of the top pressure spring, so as to avoid manual pushing of the tube.

[0066] When sampling is complete and the syringe component needs to be replaced, the stepper motor drives the lead screw nut to move the positive pressure part upward away from the syringe component, so that the syringe body of the syringe component can be removed and replaced.

[0067] The driving device includes a stepper motor, a ball screw, a screw nut, a connecting plate, a slide rail, and a slider; wherein the slide rail is installed at the guide rail bracket, one side of the slider is slidably connected to the slide rail, the other side of the slider and the connecting plate are fixed to the outer shell of the positive pressure part, and the connecting plate is also connected to the screw nut, and the positive pressure part 33 is moved up and down through the screw nut transmission.

[0068] When sampling, the positive pressure part moves downward to the syringe component and contacts the top of the syringe body. The outer cover of the positive pressure part presses the upper pressure cylinder 334 of the positive pressure part to continue moving downward, compressing the top pressure spring 332 of the guide groove 333. The elastic force of the compressed top pressure spring is applied to the top of the syringe body through the lower pressure cylinder 331 of the positive pressure part.

[0069] The sampling needle is inserted into the oil inlet in the middle of the adapter body 321 of the adapter component; the lower part of the sampling rod is connected to the sampling spring 324 placed in the sampling positioning seat 323 of the adapter component, and the top of the sampling positioning seat is threadedly connected to the sampling cap 326; the sampling rod is inserted through the sampling cap, and when the sampling rod is pressed down, the spring force of the sampling spring buffers and absorbs the shock.

[0070] The positioning seat is placed inside the adapter body and is coaxial with it. The sampling needle passes through the sampling spring and extends into the center hole of the sampling rod.

[0071] The output end of the syringe body is fitted with a replaceable sealing cap 312. When the syringe body, together with the sealing cap, passes through the circular through hole on the sample holder and is inserted into the center hole of the sampling rod, the tip of the sampling needle pierces the sealing cap. At this time, the liquid sample in the syringe body enters the oil inlet along the sampling needle. The other end of the oil inlet is connected to the inlet of the oil inlet solenoid valve.

[0072] The outlet of the oil inlet solenoid valve 322 is connected to one end of the oil outlet pipe 3212 of the adapter component, and the other end of the oil outlet pipe extends into the manifold box 7 through the manifold 8.

[0073] The oil inlet solenoid valve is a normally closed solenoid valve. When it is energized, its inlet and outlet are connected, allowing the sample in the syringe body located above the oil inlet solenoid valve to flow through the manifold to the manifold box under the action of the positive pressure spring. The sample in the manifold box is then exported to external equipment through the output port of the manifold box.

[0074] The manifold is composed of several pipes connected together, wherein a quick-connect pipe purging connector 81 is provided at the initial end of the pipes; the manifold box is provided with an inclined box partition, and a quick-connect box purging connector 82 is connected to the higher end of the box partition. A quick-connect sample outlet is provided at the lower end of the box partition for exporting samples from the manifold box.

[0075] A sampling method for an automatic quantitative batch sample dispensing device for transformer oil, the aforementioned automatic quantitative batch sample dispensing device for transformer oil, is characterized by comprising the following steps;

[0076] Step S1: After drawing the transformer oil to be tested into the syringe body, seal it with a sealing cap;

[0077] Step S2: Insert one end of the sealing cap of the syringe into the center hole of the sampling rod. At this time, the sampling needle will pierce the sealing cap.

[0078] Step S3: The stepper motor is powered on, and the positive pressure part is pressed down under the action of the lead screw nut. At this time, the top pressure spring presses the main body of each syringe and contracts, so that positive pressure is generated inside each syringe.

[0079] Step S4: Select the sample to be tested. At this time, the corresponding oil inlet solenoid valve is energized. The sample inside the corresponding syringe is led out through the manifold to the manifold box under the action of the top pressure spring. Then, it is sent to the corresponding detection device through the flow sensor at the output end of the manifold box. After the flow reaches the set value, the corresponding oil inlet solenoid valve is de-energized.

[0080] Step S5: Introduce carrier gas and blank oil through the pipeline purging quick connector and the box purging quick connector to purge the manifold and manifold box. After cleaning, proceed with the next sample injection.

[0081] In step S3, the amount of contraction deformation generated by each top pressure spring pressing the syringe body can push out all the samples in the corresponding syringe body when it is extended and released.

[0082] In this example, the syringe body is a standard 100mL syringe.

[0083] In this example, the top pressure spring of the positive pressure section can be connected to the syringe body. After the dispensing device finishes dispensing the sample, the positive pressure section rises and the top pressure spring pulls up each syringe body, causing the sharp input end of the adapter component to disengage from the sealing cap. The sealing cap contracts with its elasticity and seals the bottom of the syringe body, thus isolating the sample in the inner cavity of the syringe body from the outside.

[0084] In this example, when the dispensing device is not dispensing a sample, the positive pressure section also applies a small pressure to the syringe body with its top pressure spring. This small pressure is less than the pressure that causes the sample to flow out from the puncture site of the sealing cap, so that the inner cavity of the syringe body is in a slightly positive pressure state to prevent external air from entering.

Claims

1. An automatic quantitative sample dispensing device for transformer oil in batches, characterized in that: The dispensing device includes a sample placement bracket (2) located at the base (1); the sample placement bracket is provided with a sampling component (3) containing multiple sampling units; the sampling unit includes a positive pressure part (33), a syringe component (31), and an adapter component (32) arranged from top to bottom. The sample dispensing end of the dispensing device is connected to an external device. The syringe component is a syringe array consisting of multiple syringe bodies arranged in rows and columns for storing samples. The adapter component is an adapter array consisting of multiple adapters below the syringe array that are connected to the sample dispensing end. Each syringe body corresponds to each adapter. When the dispensing device is working, the positive pressure part is connected to the top of the syringe body with its elastic element. By applying pressure, the sharp input end of the adapter component penetrates the elastic sealing cap at the bottom of the syringe body. When the oil inlet of a certain adapter is connected to the sample dispensing end, the sample in the syringe body corresponding to that adapter flows out through the sample dispensing end. When the sharp input end of the adapter component disengages from the sealing cap, the sealing cap retracts with its elasticity and seals the bottom of the syringe body; The adapter component includes a sampling rod (325) of a sampling needle (34); the tip of the sampling needle points to the bottom of the syringe body, and the tail of the needle communicates with the oil inlet (3211) of the adapter component; the oil inlet communicates with the manifold (8) of the dispensing device via an oil inlet solenoid valve (322); when the dispensing device is working, the positive pressure part applies pressure to the top of the syringe body (311) of the syringe component to make it in a positive pressure state; the sampling needle pierces the bottom of the syringe body, so that the sample in the syringe body can flow out to the oil inlet through the sampling needle; the dispensing device extracts samples from different sampling units through the manifold by selecting and opening the oil inlet solenoid valves at different oil inlets; The adapter component is fixed on the base, and the syringe component is inserted into the adapter component to form a clearance fit. The base is provided with a vertical guide rail bracket (4). The positive pressure part is driven by the driving device (5) to move vertically along the guide rail bracket. When it moves downward to the syringe component, it contacts the top of the syringe body. The positive pressure part is a micro-elastic positive pressure component including a top pressure spring. When sampling, when the positive pressure part descends, its top pressure spring (332) moves downward to press the syringe body (311) to generate positive pressure inside, so as to prevent external air from entering, and to make the plunger of the syringe body press the sample inside to be discharged under the pressure of the top pressure spring, so as to avoid manual pushing of the tube. When the sampling is completed and the syringe component needs to be replaced, the stepper motor drives the lead screw nut to move the positive pressure part upward away from the syringe component, so that the syringe body of the syringe component can be removed and replaced. The sampling needle is inserted into the oil inlet in the middle of the adapter body (321) of the adapter component; the lower part of the sampling rod is connected to the sampling spring (324) placed in the sampling positioning seat (323) of the adapter component, and the top of the sampling positioning seat is threadedly connected to the sampling cap (326); the sampling rod is inserted through the sampling cap, and when the sampling rod is pressed down, the spring force of the sampling spring buffers and absorbs the shock. The positioning seat is placed inside the adapter body and is coaxial with it. The sampling needle passes through the sampling spring and extends into the center hole of the sampling rod.

2. The automatic quantitative sample dispensing device for transformer oil in batches according to claim 1, characterized in that: The driving device includes a stepper motor, a ball screw, a screw nut, a connecting plate, a slide rail, and a slider; wherein the slide rail is installed at the guide rail bracket, one side of the slider is slidably connected to the slide rail, the other side of the slider and the connecting plate are fixed on the outer shell of the positive pressure part, and the connecting plate is also connected to the screw nut, so that the positive pressure part (33) moves up and down through the screw nut transmission. When sampling, the positive pressure part moves downward to the syringe component and contacts the top of the syringe body. The outer shell of the positive pressure part presses the upper pressure cylinder (334) of the positive pressure part to continue moving downward, compressing the top pressure spring (332) of the guide groove (333). The elastic force of the compressed top pressure spring is applied to the top of the syringe body through the lower pressure cylinder (331) of the positive pressure part.

3. The automatic quantitative sample dispensing device for transformer oil in batches according to claim 2, characterized in that: The output end of the syringe body is fitted with a replaceable sealing cap (312). When the syringe body, together with the sealing cap, passes through the circular through hole on the sample holder and is inserted into the center hole of the sampling rod, the tip of the sampling needle pierces the sealing cap. At this time, the liquid sample in the syringe body enters the oil inlet along the sampling needle. The other end of the oil inlet is connected to the inlet of the oil inlet solenoid valve.

4. The automatic quantitative sample dispensing device for transformer oil in batches according to claim 3, characterized in that: The outlet of the oil inlet solenoid valve (322) is connected to one end of the oil outlet pipe (3212) of the adapter component, and the other end of the oil outlet pipe extends into the manifold box (7) through the manifold (8).

5. The automatic quantitative sample dispensing device for transformer oil in batches according to claim 4, characterized in that: The oil inlet solenoid valve is a normally closed solenoid valve. When it is energized, its inlet and outlet are connected, allowing the sample in the syringe body located above the oil inlet solenoid valve to flow through the manifold to the manifold box under the action of the positive pressure spring. The sample in the manifold box is then exported to external equipment through the output port of the manifold box.

6. The automatic quantitative sample dispensing device for transformer oil in batches according to claim 5, characterized in that: The manifold is composed of several pipes connected together, wherein a quick-connect pipe purging connector (81) is provided at the initial end of the pipes; an inclined box partition is provided inside the manifold box, and a quick-connect box purging connector (82) is connected to the higher end of the box partition. A quick-connect sample outlet is provided at the lower end of the box partition for sample outlet from the manifold box.

7. A sampling method for an automatic quantitative batch sample dispensing device for transformer oil, using the automatic quantitative batch sample dispensing device for transformer oil as described in claim 6, characterized in that: Includes the following steps; Step S1: After drawing the transformer oil to be tested into the syringe body, seal it with a sealing cap; Step S2: Insert one end of the sealing cap of the syringe into the center hole of the sampling rod. At this time, the sampling needle will pierce the sealing cap. Step S3: The stepper motor is powered on, and the positive pressure part is pressed down under the action of the lead screw nut. At this time, the top pressure spring presses the main body of each syringe and contracts, so that positive pressure is generated inside each syringe. Step S4: Select the sample to be tested. At this time, the corresponding oil inlet solenoid valve is energized. The sample inside the corresponding syringe is led out through the manifold to the manifold box under the action of the top pressure spring. Then, it is sent to the corresponding detection device through the flow sensor at the output end of the manifold box. After the flow reaches the set value, the corresponding oil inlet solenoid valve is de-energized. Step S5: Introduce carrier gas and blank oil through the pipeline purging quick connector and the box purging quick connector to purge the manifold and manifold box. After cleaning, proceed with the next sample injection.

8. The sampling method of the automatic quantitative sample dispensing device for transformer oil batches according to claim 7, characterized in that: In step S3, the amount of contraction deformation generated by each top pressure spring pressing the syringe body can push out all the samples in the corresponding syringe body when it is extended and released.

Images