Automatic blood sampling equipment and control method thereof

Abstract

The invention provides automatic blood sampling equipment and a control method thereof. The device comprises a machine shell, a control unit, a driving mechanism, a needle head, a positioning mechanism, a blood collecting device and a blood collection amount detection sensor. The driving mechanism comprises a first electromagnet and a linear module and is used for achieving puncturing and retreating of a needle head. The positioning mechanism comprises a second electromagnet and a retainer and is used for locking the needle after the needle returns; the blood collecting device comprises a three-way fluid connector, a blood collecting test tube, a waste blood test tube, a first vacuum pump and a second vacuum pump and is used for collecting waste blood and detected blood samples step by step. According to the control method, through sequential control of deep puncturing, back-off and locking, the needle head is driven to puncture into a first preset depth, back to a second preset depth and then locked, and then the second vacuum pump and the first vacuum pump are started in sequence to complete blood sampling. The puncture depth is precisely and dynamically controlled, the blood sample quality is improved, and the core technical problems that in an existing peripheral blood sampling technology, depth control is not accurate, the blood sample is prone to being polluted, the pain feeling of a patient is high, and professionals depend on the existing peripheral blood sampling technology are effectively solved.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, and in particular to an automated peripheral blood collection device and its control method that can precisely control the puncture depth and automatically complete blood collection. Background Technology

[0002] Peripheral blood sampling is a common clinical technique that involves puncturing the capillary network in the superficial layer of the skin to collect a small blood sample. Compared with traditional venous blood sampling, it has the advantages of being convenient, minimally invasive, less painful, and having a faster recovery. However, current peripheral blood sampling procedures, whether using manual or semi-automatic lancets, still heavily rely on the operator's personal skills and experience, and there are still many unresolved challenges:

[0003] Poor precision in depth control: Puncture depth is crucial for successful peripheral blood collection. Insufficient depth results in insufficient blood volume, requiring repeated punctures and increasing patient discomfort; excessive depth can damage subcutaneous nerve endings or touch the periosteum, causing severe pain and even tissue damage and infection. This is especially problematic for individuals with vastly different skin thicknesses, such as newborns, children, adults, the elderly, and obese or underweight individuals, where operators struggle to precisely control the depth by touch, leading to inconsistent results.

[0004] The application of negative pressure is crude: In existing technologies, after the skin is broken, the operator usually relies on manually squeezing or massaging the blood collection site to obtain a sufficient amount of blood sample. This external squeezing causes tissue fluid to mix into the blood sample, severely diluting the blood sample and potentially damaging blood cells, affecting the accuracy of the test results. At the same time, the rough squeezing method itself can also exacerbate the patient's pain and cause local tissue damage.

[0005] Unstable success rate and patient experience: Due to the reasons mentioned above, capillary blood sampling, especially for individuals with thin blood vessels and low tolerance, has a high failure rate and repeat puncture rate. This not only increases the workload and stress of medical staff but also causes unnecessary physical pain and psychological fear for patients.

[0006] High dependence on professional medical personnel: Although fingertip blood glucose monitoring technology has successfully enabled home testing, its detection range is limited. For more complex blood tests such as complete blood counts, a relatively large amount of capillary blood still needs to be collected and the sample quality ensured. However, the existing capillary blood collection technology still requires a high level of expertise from medical personnel, let alone ordinary users, who simply cannot master it. Therefore, patients must go to medical institutions in person and go through a series of cumbersome steps such as registration and queuing. This is not only time-consuming and laborious, but also increases the risk of cross-infection among patients, and brings great inconvenience to patients with limited mobility, those undergoing long-term monitoring of chronic diseases, and residents in remote areas.

[0007] To address the aforementioned issues, the field has been seeking an automated peripheral blood collection solution. This involves not simply mechanizing the "puncture" action, but rather fundamentally and systematically solving the three core challenges of "precise depth control," "gentle and contamination-free blood collection," and "safe operation by non-professionals." Summary of the Invention

[0008] The purpose of this invention is to overcome the shortcomings of existing technologies and provide an automated capillary blood collection device and its control method that integrates puncture, blood collection, and waste blood separation. It not only boasts a high degree of automation but also accurately and intelligently controls the puncture depth and automatically separates waste blood from the blood sample, thereby greatly improving the success rate of blood collection and the quality of the blood sample. Even non-professionals can operate it safely.

[0009] To achieve the above-mentioned objectives, the present invention adopts the following technical solution:

[0010] On one hand, this invention provides an automated blood collection device, including a housing, a control unit, a drive mechanism, a needle, a positioning mechanism, a blood collection device, and a blood volume detection sensor. The drive mechanism includes a first electromagnet and a linear module driven by the first electromagnet to perform linear motion, used to achieve precise puncture and retraction of the needle. The positioning mechanism includes a second electromagnet and a stop driven by the second electromagnet, used to mechanically lock the needle when it retracts to a preset depth, ensuring the stability of the blood collection process. The blood collection device includes a three-way fluid connector, a blood collection tube, a waste blood tube, a first vacuum pump, and a second vacuum pump, and achieves stepwise collection of waste blood and standard blood samples through a flow path design. The blood volume detection sensor is used to monitor the blood volume in the blood collection tube to achieve automatic termination of blood collection.

[0011] Preferably, a first limit switch and a second limit switch can be respectively provided at both ends of the linear module's travel to limit the movement range of the linear module and improve the safety and stability of the equipment operation.

[0012] Preferably, the openings of the blood collection tube and the waste blood tube can be sealed with a three-way tube cap to simplify the flow path connection and improve the sealing and reliability of the system.

[0013] Preferably, the control unit can be configured to dynamically adjust the first preset depth and the second preset depth based on user input or a preset blood collection mode, so as to adapt to the specific needs of different populations and blood collection sites.

[0014] On the other hand, the present invention provides a control method for the aforementioned automated blood collection device. This method, executed by the control unit, includes the following steps: First, the control drive mechanism pushes the needle into the skin to a first preset depth; then, the control drive mechanism resets, causing the needle to retract; when the needle retracts to a second preset depth, the positioning mechanism is activated to stably lock the needle in that position; next, the second vacuum pump is activated to draw the initial blood sample into the waste blood tube; after a predetermined time, the second vacuum pump is stopped; subsequently, the first vacuum pump is activated to draw subsequent blood samples into the blood collection tube; when the blood volume detection sensor detects that the blood volume in the blood collection tube has reached a set value, the first vacuum pump is stopped and a blood collection completion signal is issued; finally, all components of the control device are reset, and the needle is safely withdrawn from the skin.

[0015] As a further optimization of the present invention, when it is determined that the needle has retracted to the second preset depth, it can be achieved by timing or by a signal from a position sensor, thus balancing cost and accuracy requirements.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0017] It achieves precise and adaptive control of puncture depth: through the timing control and adjustable parameters of "deep puncture-retraction-locking", it systematically solves the problem of depth control caused by differences in skin thickness and human feel, ensuring the consistency and success rate of operation.

[0018] It fundamentally improves blood sample quality: Through the design of dual vacuum pumps and dual test tubes, it realizes automatic and physical separation of waste blood and test blood samples, effectively avoiding blood sample contamination or hemolysis caused by tissue fluid mixing and manual squeezing, and ensuring the reliability of test results.

[0019] Significantly improved patient experience and ease of use: The fully automated process and precise control greatly reduce patient pain and fear. "One-button" operation and built-in safety mechanisms (such as limit switches) significantly lower the barrier to entry, enabling non-professionals to complete blood collection safely and efficiently.

[0020] It possesses high integration and scalability: the modular design (such as the three-way test tube cap) simplifies assembly and use. At the same time, this architecture easily integrates various sensors, enabling advanced functions such as closed-loop control, intelligent diagnostics, and data traceability, demonstrating its enormous potential as a platform-based invention. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the casing of the automatic blood collection device of the present invention.

[0022] Figure 2This is a schematic diagram of the internal structure of the automatic blood collection device of the present invention.

[0023] Figure 3 This is a schematic diagram of the internal structure of the automatic blood collection device of the present invention.

[0024] Figure 4 This is a partial structural diagram of the automatic blood collection device of the present invention during the non-blood collection stage.

[0025] Figure 5 This is a partial structural diagram of the automatic blood collection device of the present invention during the blood collection stage.

[0026] Explanation of the labels in the diagram:

[0027] 11-Housing; 111-Blood collection port; 112-Charging port; 113-Data transmission port; 114-Strap fixing hole; 12-Power supply module; 13-Display screen; 14-Button; 20-Control unit; 31-First electromagnet; 311-Reset spring; 312-Push rod; 32-Linear module; 321-Slider; 322-Linear guide rail; 33-First limit switch; 34-Second limit switch; 41-Second electromagnet; 42-Stop; 51-Needle; 52-Needle seat; 61-First vacuum pump; 62-Second vacuum pump; 71-T-connector; 72-Blood collection tube; 73-Waste blood tube; 80-Blood volume detection sensor. Detailed Implementation

[0028] The present invention will now be described in detail with reference to the accompanying drawings and by way of several embodiments, which are intended to fully disclose the present invention and provide multi-level and comprehensive support for the claims. Example 1: Standard blood collection device based on timing control and mechanical locking

[0029] This embodiment provides an automated blood collection device that is compact, cost-controllable, and meets medical device safety standards, aiming to provide a reliable peripheral blood collection solution for primary healthcare institutions, health check centers, and qualified home users.

[0030] Core structure implementation:

[0031] Housing and Control Unit: The housing 11 houses all components, including a power supply module 12, a display screen 13, operation buttons 14, a blood collection port 111, a charging port 112, a data transmission port 113, and a strap fixing hole 114. Users can select blood collection modes, check status, and start the blood collection process via the display screen 13 and buttons 14. Additionally, for areas that are difficult to fix, such as the forearm or upper arm, the device can be securely attached to the skin via the strap fixing hole 114. For fingertip blood collection, users can simply place their hand on a table and press the blood collection port 111 against the fingertip.

[0032] Drive Mechanism: The drive mechanism employs a push-type first electromagnet 31, whose push rod 312 houses a return spring 311. When energized, the push rod 312 overcomes the spring force and rapidly ejects towards the direction where the needle 51 is mounted, causing the needle 51 to extend beyond the housing 11; when de-energized, the push rod 312 retracts under the action of the return spring 311. The end of the push rod 312 is machined with a threaded hole and directly connected to the slider 321 of the linear module 32 via a set screw, thus forming a rigid linkage mechanism. A key insight of this invention lies in fully utilizing the excellent speed repeatability of the reset process of such standard electromagnets; the rigid direct connection between the push rod and the slider ensures backlash-free and highly consistent power transmission. The spring constant of the return spring 311 and the total mass of the entire moving assembly together determine the highly predictable average speed of the retraction motion. This physical characteristic is the core foundation and basis for subsequently employing a low-cost, high-reliability "timing method" to accurately determine the needle retraction depth.

[0033] Needle: The needle 51 is mounted on the slider 321 via a medical-grade plastic needle holder 52, and the needle holder 52 is in fluid communication with the needle 51; wherein, the drive mechanism is configured to completely retract the needle 51 into the housing 10 when not in operation.

[0034] Positioning Mechanism: The second electromagnet 41 drives an L-shaped stainless steel stop 42. A V-shaped groove with a precise fit is provided on the side of the slider 321. When the second electromagnet 41 is activated, the stop 42 precisely engages in this groove. This "over-positioning" mechanical locking design ensures the absolute stability of the needle 51's position during blood collection, guaranteeing the stability of blood collection from a mechanical structural perspective.

[0035] Blood collection device: The blood collection device includes a three-way fluid connector 71, a blood collection tube 72, a waste blood tube 73, a first vacuum pump 61, and a second vacuum pump 62. The first port of the three-way fluid connector 71 is in fluid communication with the needle hub 52, the second port is in fluid communication with the blood collection tube 72, and the third port is in fluid communication with the waste blood tube 73. The first vacuum pump 61 is in fluid communication with the blood collection tube 72, and the second vacuum pump 62 is in fluid communication with the waste blood tube 73. The needle 51, needle hub 52, three-way fluid connector 71, blood collection tube 72, waste blood tube 73, and all connecting tubing together constitute a pre-assembled, sterile, disposable assembly. This design strictly adheres to the hygiene standards for medical devices, achieving "one person, one use, one disposal," fundamentally eliminating the risk of cross-infection and greatly simplifying user operation.

[0036] Control process, parameter basis, and creative embodiment:

[0037] Intelligent puncture (Step S1): After the user selects the blood collection mode via the display screen 13 and the button 14, the control unit 20 sends a pulse signal of a specific width to the first electromagnet 31. This pulse width is pre-calibrated to ensure that the needle 51 penetrates the skin with optimal kinetic energy and reaches a first preset depth H1. For example, in 'adult fingertip' mode, the pulse width t = 20ms is set to ensure that the needle reliably penetrates the epidermis to a depth of H1 = 3.0mm.

[0038] Retraction and Locking (Steps S2 and S3): After the pulse ends, the first electromagnet 31 is de-energized, and the needle 51 retracts under the action of the return spring 311. Simultaneously, the control unit 20 starts a timer. The goal is to stabilize the needle tip from a first preset depth H1 to a second preset depth H2. The retraction distance is H1-H2. Based on a pre-calibrated average retraction speed v (e.g., 0.1 mm / ms), the retraction time T1 = (H1-H2) / v is calculated. When the timer reaches T1, the control unit 20 immediately triggers the second electromagnet 41, driving the stop 42 to complete the locking. This "deep puncture-retraction-locking" timing sequence is the inventive aspect of this invention. It uses a simple timing method to simulate, at low cost and with high reliability, the skillful technique of a skilled nurse's "fine-tuning after skin puncture," achieving accurate and repeatable judgment of the critical state of "retraction to the second depth."

[0039] Step-by-step negative pressure blood collection:

[0040] Step S4: Collect waste blood; control the second vacuum pump 62 to start and run for a predetermined time T2 (e.g., 0.5 seconds) to draw the initial blood sample, which may contain tissue fluid or skin contaminants, into the waste blood test tube 73.

[0041] Step S5: Control the second vacuum pump 62 to stop.

[0042] Step S6: Collect and test blood samples; control the first vacuum pump 61 to start and run for a predetermined time T3 (e.g., 2 seconds) to draw the subsequent pure blood sample into the blood collection tube 72.

[0043] Step S7: When the blood volume detection sensor 80 detects that the blood volume in the blood collection tube 72 has reached the set value (e.g., 100-200 μL), it controls the first vacuum pump 61 to stop and sends a blood collection completion signal.

[0044] Step S8 (Safety Reset): After the entire blood collection process is completed, the control unit 20 performs a reset operation in sequence: the second electromagnet 41 is de-energized to retract the stop 42 and unlock it; subsequently, the entire drive mechanism returns to its original position under the action of the reset spring 311, the needle 51 is safely withdrawn from the skin, and an audible and visual prompt is issued to notify the user.

[0045] Multi-scenario application parameters (examples): Blood collection mode First preset depth H1 (mm) Second preset depth H2 (mm) Target blood volume V (μL) adult fingertips 3.0 2.0 100-200 adult forearm 2.5 1.5 150-250 Children's fingertips 2.2 1.5 100-150 Newborn heel 1.5 1.0 50-100

[0046] Based on Example 1, this embodiment addresses scenarios with extremely high requirements for safety and accuracy, such as neonatal intensive care, high-end medical examination centers, and clinical research. By introducing sensor technology, it achieves performance improvement and functional expansion.

[0047] Core upgrades and optimizations:

[0048] High-precision depth closed-loop control: A high-precision linear optical encoder is integrated on the linear module 32, which can provide real-time and continuous feedback on the absolute position of the slider 321 with a resolution of 0.01mm. This position sensor provides a direct and accurate means of determining the retraction depth.

[0049] Pressure feedback system: As a preferred extension function, this embodiment can also integrate a micro-pressure sensor for real-time monitoring of pressure changes in the negative pressure flow path, for advanced safety monitoring and diagnostics.

[0050] Work process and its advanced features:

[0051] Millimeter-level puncture accuracy: In steps S1 and S3, the control unit 20 continuously reads encoder data; when it detects that the needle 51 has precisely reached the first preset depth, it immediately cuts off the power supply to the first electromagnet 31; when it precisely reaches the second preset depth during retraction, it immediately triggers locking. This improves the depth control accuracy to within ±0.02mm, providing an extremely high-precision implementation scheme for the core depth control method of this invention.

[0052] Process safety monitoring and intelligent diagnostics: Pressure sensors are used for intelligent diagnostics. If the pressure fails to drop normally after startup, it is determined that the flow path is blocked or there is a leak; if the pressure curve is abnormal during blood collection, it can be determined that blood collection is not smooth. Once the above abnormal conditions are detected, the control unit 20 will immediately stop the blood collection process and issue an audible and visual alarm to prompt the user to intervene and check, thereby greatly improving the safety of the equipment.

[0053] Data recording and traceability: The device can record data such as the depth, blood volume, pressure curve, and mode used for each blood collection, and upload it to the medical information system via Bluetooth or the data transmission port 113, meeting the strict requirements for quality control and sample traceability in high-end medical scenarios.

[0054] Creative Summary: Example 2 demonstrates the high scalability of the core technical architecture of this invention. By integrating position sensors, a higher-precision implementation path is provided for the core control method; by integrating pressure sensors, etc., advanced safety monitoring functions are added. This proves that the "deep piercing-retreating-locking" core architecture of this invention is a platform-type invention, capable of achieving a smooth upgrade from "basic" to "enhanced" without changing its basic working principle and protection scope, demonstrating its outstanding substantive features and significant progress.

Claims

1. An automated blood collection device, characterized in that, include: chassis; The control unit is located inside the housing; A drive mechanism is disposed inside the housing and electrically connected to the control unit. The drive mechanism includes a first electromagnet and a linear module driven by the first electromagnet to perform linear motion. The needle is mounted on the linear module via a needle holder; wherein the drive mechanism is configured to fully retract the needle into the housing when not in operation; A positioning mechanism is disposed inside the housing and electrically connected to the control unit. The positioning mechanism includes a second electromagnet and a stop driven by the second electromagnet. The blood collection device, housed within the casing, includes a three-way fluid connector, a blood collection tube, a waste blood tube, a first vacuum pump, and a second vacuum pump. The first port of the three-way fluid connector is in fluid communication with the needle hub, the second port is in fluid communication with the blood collection tube, and the third port is in fluid communication with the waste blood tube. The first vacuum pump is in fluid communication with the blood collection tube and is used to allow blood to flow through the three-way fluid connector and be drawn into the blood collection tube when it is started. The second vacuum pump is in fluid communication with the waste blood test tube and is used to allow blood to flow through the three-way fluid connector and be drawn into the waste blood test tube when it is started. A blood volume detection sensor is located near the blood collection tube and is signal-connected to the control unit. The control unit is configured to perform the control method as described in claim 2.

2. A control method for the automated blood collection device as described in claim 1, characterized in that, The method includes the following steps: Step S1: Control the drive mechanism to push the needle out and reach a first preset depth; Step S2: Control the drive mechanism to reset, causing the needle to retract; Step S3: When the needle retracts to the second preset depth, control the positioning mechanism to lock the linear module or needle through the stop to fix the needle position; Step S4: Control the second vacuum pump to start, and draw the initial blood sample into the waste blood test tube; Step S5: After a predetermined time has elapsed, control the second vacuum pump to stop; Step S6: Control the first vacuum pump to start, and draw subsequent blood samples into the blood collection tube; Step S7: When the blood collection volume detection sensor detects that the blood collection volume in the blood collection tube has reached the set value, it controls the first vacuum pump to stop and sends a blood collection completion signal. Step S8: After blood collection is completed, the following steps are executed in sequence: control the second electromagnet to reset so that the stop can be retracted and unlocked, thereby allowing the needle to be completely withdrawn from the blood collection site.

3. The automated blood collection device according to claim 1, characterized in that, The linear module is equipped with a first limit switch and a second limit switch at both ends of its travel to limit the range of motion of the linear module.

4. The automated blood collection device according to claim 1, characterized in that, The linear module includes a linear guide rail and a slider. The push rod of the first electromagnet is fixedly connected to the slider through a connector, and the needle is mounted on the slider through a needle holder.

5. The automated blood collection device according to claim 1, characterized in that, The stop is an L-shaped pin or a claw structure. When the second electromagnet is activated, the stop extends and abuts against the side of the slider or the component connected to the needle.

6. The automated blood collection device according to claim 1, characterized in that, The blood collection tube and the waste blood tube are each sealed with a three-way cap; the other two ports of the three-way cap of the blood collection tube are respectively fluidly connected to the second port of the three-way fluid connector and the first vacuum pump; the other two ports of the three-way cap of the waste blood tube are respectively fluidly connected to the third port of the three-way fluid connector and the second vacuum pump.

7. The automated blood collection device according to claim 1, characterized in that, The control unit is configured to dynamically adjust the first preset depth and the second preset depth based on user input or a preset blood collection mode.

8. The control method according to claim 2, characterized in that, In step S3, the needle is determined to have retracted to the second preset depth by timing or by a signal from a position sensor.

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