Double-path pulse counting-based low-power-consumption self-checking bubble sensor and method

Abstract

The invention discloses a double-path pulse counting-based low-power-consumption self-checking bubble sensor, which comprises a control chip MCU (Microprogrammed Control Unit) module, a double-pulse ultrasonic wave generation driving circuit, an ultrasonic wave transmitting terminal, an ultrasonic wave receiving terminal, a signal amplification circuit and a signal comparator, and is characterized in that the control chip MCU module is connected with the double-pulse ultrasonic wave generation driving circuit; the double-pulse ultrasonic generation driving circuit is connected with the ultrasonic transmitting terminal, the ultrasonic transmitting terminal and the ultrasonic receiving terminal are oppositely arranged, the ultrasonic receiving terminal is connected with the signal amplifying circuit, the signal amplifying circuit is connected with the comparator, and the comparator is connected with the control chip MCU module. By adopting the technical scheme, the low-power-consumption self-checking bubble sensor and method based on double-path pulse counting have the advantages of low power consumption, high real-time performance, self-checking function, high accuracy and product miniaturization.

Description

Technical Field

[0001] The invention relates to the field of bubble sensors, and in particular to a low-power self-checking bubble sensor based on dual-path pulse counting and a method thereof. Background Art

[0002] In the use of existing medical infusion pumps, in order to prevent bubbles in the pipeline from being infused into the human body during the infusion process, which may cause adverse reactions, a bubble sensor is usually used to detect the bubbles in the pipeline.

[0003] Generally, portable infusion pumps are powered by 2 AA alkaline dry batteries. For portable infusion pumps or electronic injection pumps used for analgesia or chemotherapy, the clinical administration time is required to be able to maintain continuous operation for at least 48 hours, which makes the power consumption requirements of the product very high. Traditional bubble sensors require a relatively high power supply voltage and high power consumption during operation, which affects the use time of portable infusion pumps or electronic injection pumps.

[0004] In addition, a malfunction of a traditional bubble sensor may cause a false alarm or fail to identify bubbles, and there is no self-detection method, which poses a great risk to the clinical use of medical infusion pumps and poses an obvious safety hazard. Summary of the invention

[0005] In order to solve the above problems, the present invention provides a low-power self-checking bubble sensor and method based on dual-path pulse counting.

[0006] The present invention discloses a low-power self-checking bubble sensor based on dual-path pulse counting, comprising a control chip MCU module, a dual-pulse ultrasonic wave generating drive circuit, an ultrasonic wave transmitting terminal, an ultrasonic wave receiving terminal, a signal amplifying circuit, and a signal comparator. The control chip MCU module is connected to the dual-pulse ultrasonic wave generating drive circuit, the dual-pulse ultrasonic wave generating drive circuit is connected to the ultrasonic wave transmitting terminal, the ultrasonic wave transmitting terminal and the ultrasonic wave receiving terminal are arranged opposite to each other, the ultrasonic wave receiving terminal is connected to the signal amplifying circuit, the signal amplifying circuit is connected to the comparator, and the comparator is connected to the control chip MCU module.

[0007] In the above solution, the double-pulse ultrasonic wave generating driving circuit is connected to the signal amplifying circuit.

[0008] In the above solution, the control chip MCU module generates an excitation pulse of 2 MHz.

[0009] In the above solution, the control chip MCU module generates adjustable PWM pulses.

[0010] A low-power self-checking bubble sensor method based on dual-path pulse counting includes the following steps:

[0011] S1: System startup;

[0012] S2: Send out excitation pulse and shaping pulse;

[0013] S3: The rising edge interrupt of the shaping pulse starts counting the excitation pulses;

[0014] S4: The falling edge of the shaping pulse interrupts the reading of the number of excitation pulses;

[0015] S5: Does the number of pulses exceed the threshold? If yes, go to S6; if no, go to S9;

[0016] S6: no bubble counting;

[0017] S7: Is the continuous no-bubble count less than the set value? If yes, go to S8; if not, go to S2;

[0018] S8: Send a bubble-free message; go to S2;

[0019] S9: Bubble counting;

[0020] S10: Is the continuous no-bubble count greater than or equal to the set value? If yes, go to S11; if not, go to S2;

[0021] S11: Sending bubble information;

[0022] S12: Stop sending pulse signals.

[0023] The advantages and beneficial effects of the present invention are as follows: the present invention provides a low-power self-checking bubble sensor and method based on dual-path pulse counting, which has the following advantages:

[0024] 1. Low power consumption. First, the characteristics of the ultrasonic transmitter and the ultrasonic receiver are matched. Under the same conditions, the signal output by the ultrasonic receiving terminal 4 is very stable. Secondly, the unique circuit design can amplify the ultrasonic receiving signal while reducing the driving power of the ultrasonic transmitting terminal 3. After passing through the amplifier, it can still meet our design requirements. The overall power consumption of the new bubble sensor circuit is less than 15mW. Referring to the common bubble sensors on the market, which generally consume more than 90mW, the power consumption of the bubble sensor is greatly reduced, which has obvious power consumption advantages for battery-powered portable infusion pumps or electronic injection pumps.

[0025] 2. High real-time performance. The control chip MCU module 1 is used to directly control the double pulse output detection. There is no device that causes delay in the circuit, and the control is processed by interrupt reception. Compared with the traditional hardware counter delay, the detection real-time performance is high, and there is almost no delay effect, which is very effective for application scenarios with high requirements for bubble detection real-time performance.

[0026] 3. Self-test function. The control chip MCU module 1 of the bubble sensor controls the dual-pulse ultrasonic drive circuit 2 to output a simulated intermittent pulse group by controlling the self-test control signal. The simulated intermittent pulse group is input to the control chip MCU module 1 through the signal amplification circuit 5 and the comparator 6 to form a detection loop. The control chip MCU module 1 determines whether the entire circuit loop is abnormal by counting. The self-test function of the bubble sensor can solve the risk of harm caused by bubbles during the clinical use of medical infusion pumps.

[0027] 4. High accuracy. The characteristics of the ultrasonic transmitter and the ultrasonic receiver are matched, and the signal output by the ultrasonic receiving terminal 4 is very stable under the same conditions. At the same time, by counting the pulses of the captured ultrasonic intermittent pulse group and performing multiple consecutive same-state detection and judgment, accurate judgment of bubble detection is achieved.

[0028] 5. Product miniaturization. After optimizing the circuit, a simpler circuit design is adopted, which reduces the cost of the product and improves the stability of the product. It can be controlled on a PCB with an area of ​​10mm×15mm, reducing the occupied space, which is conducive to the miniaturization and lightweight of the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0030] Figure 1 is a system block diagram of the present invention;

[0031] Figure 2 It is a flow chart of the present invention.

[0032] In the figure: 1. Control chip MCU module 2. Double pulse ultrasonic generation drive circuit

[0033] 3. Ultrasonic transmitting terminal 4. Ultrasonic receiving terminal

[0034] 5. Signal amplification circuit 6. Signal comparator DETAILED DESCRIPTION

[0035] The specific implementation of the present invention is further described below in conjunction with the accompanying drawings and embodiments. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the protection scope of the present invention.

[0036] like Figure 1As shown, the present invention is a low-power self-checking bubble sensor based on dual-path pulse counting, comprising a control chip MCU module 1, a dual-pulse ultrasonic generating drive circuit 2, an ultrasonic transmitting terminal 3, an ultrasonic receiving terminal 4, a signal amplifying circuit 5, and a signal comparator 6. The control chip MCU module 1 is connected to the dual-pulse ultrasonic generating drive circuit 2, the dual-pulse ultrasonic generating drive circuit 2 is connected to the ultrasonic transmitting terminal 3, the ultrasonic transmitting terminal 3 and the ultrasonic receiving terminal 4 are arranged opposite to each other, the ultrasonic receiving terminal 4 is connected to the signal amplifying circuit 5, the signal amplifying circuit 5 is connected to the comparator 6, and the comparator 6 is connected to the control chip MCU module 1.

[0037] The double-pulse ultrasonic wave generation and driving circuit 2 is connected to the signal amplifying circuit 5 .

[0038] The control chip MCU module 1 generates a 2MHz excitation pulse.

[0039] The control chip MCU module 1 generates adjustable PWM pulses.

[0040] Functions of components: The control chip MCU module 1 is used to generate and output 2MHz excitation pulses and adjustable PWM pulses (40K frequency, adjustable duty cycle) and receive feedback signals.

[0041] The driving circuit 2 for generating double-pulse ultrasonic waves drives the ultrasonic transmitting terminal to emit ultrasonic signals by controlling two pulse signals of the chip MCU module 1.

[0042] The ultrasonic transmitting terminal 3 emits an ultrasonic pulse signal under the drive of the driving circuit.

[0043] The ultrasonic receiving terminal 4 receives the ultrasonic pulse signal passing through the pipeline.

[0044] The signal amplifying circuit 5 amplifies the received ultrasonic pulse signal.

[0045] The comparator 6 compares the pulse signal amplified by the signal amplifying circuit 5 with a set threshold value, so as to obtain a pulse signal that can be recognized by the control chip MCU module 1.

[0046] like Figure 2 As shown, a low-power self-checking bubble sensor method based on dual-path pulse counting includes the following steps;

[0047] S1: System startup;

[0048] S2: Send out excitation pulse and shaping pulse;

[0049] S3: The rising edge interrupt of the shaping pulse starts counting the excitation pulses;

[0050] S4: The falling edge of the shaping pulse interrupts the reading of the number of excitation pulses;

[0051] S5: Does the number of pulses exceed the threshold? If yes, go to S6; if no, go to S9;

[0052] S6: no bubble counting;

[0053] S7: Is the continuous no-bubble count less than the set value? If yes, go to S8; if not, go to S2;

[0054] S8: Send a bubble-free message; go to S2;

[0055] S9: Bubble counting;

[0056] S10: Is the continuous no-bubble count greater than or equal to the set value? If yes, go to S11; if not, go to S2;

[0057] S11: Sending bubble information;

[0058] S12: Stop sending pulse signals.

[0059] This product applies the bubble detection design principle as follows:

[0060] 1) Output 2MHz excitation pulse and shaped pulse with adjustable duty cycle through control chip MCU module 1.

[0061] 2) The 2 MHz excitation pulse and the high level of the shaped pulse with adjustable duty cycle are combined by the double-pulse ultrasonic drive circuit 2 to generate an interval pulse group with a frequency of 2 MHz.

[0062] 3) The 2MHz interval pulse group drives the ultrasonic transmitting end 3 to emit interval ultrasonic waves through the double-pulse ultrasonic driving circuit 2, and the ultrasonic waves pass through the infusion pipeline.

[0063] 4) The ultrasonic receiving terminal 4 receives the signal passing through the infusion pipeline and samples the signal.

[0064] 5) The signal amplifying circuit 5 amplifies the sampled signal passing through the infusion pipeline.

[0065] 6) The amplified pulse signal is compared with the set voltage level threshold by the comparator 6 and converted into a PWM waveform that can be recognized by the control chip MCU module 1.

[0066] 7) The control chip MCU module 1 captures the rising and falling edge interrupt signals of the adjustable shaped pulse 8, uses the timer to start counting the PWM waveform processed by the comparator 6 at the rising edge interrupt, and reads the count number at the falling edge interrupt. The count is for the number of pulses of the intermittent ultrasonic pulse group passing through the infusion pipeline. If the number of pulses of the intermittent ultrasonic pulse group received by the control chip MCU module 1 is greater than or equal to the pulse setting value, the control chip MCU module 1 receives the ultrasonic signal and outputs a bubble-free state signal. If the number of pulses of the intermittent ultrasonic pulse group received by the control chip MCU module 1 is less than the pulse setting value, the control chip MCU module 1 does not receive the ultrasonic signal or receives an ultrasonic signal with an insufficient number of pulses, indicating that there is a steam drum in the infusion pipeline, and the control chip MCU module 1 outputs a bubble state signal.

[0067] 8) The control chip MCU module 1 performs multiple consecutive same-state judgments on the output bubble status signal described in step 7 to eliminate interference signals and ensure the accuracy of the final output bubble status.

[0068] 9) The bubble sensor self-test function is implemented as follows. The control chip MCU module 1 controls the dual-pulse ultrasonic drive circuit 2 to output a simulated intermittent pulse group by controlling the self-test control signal. The simulated intermittent pulse group is input to the control chip MCU module 1 through the signal amplification circuit 5 and the comparator 6 to form a detection loop. The control chip MCU module 1 determines whether the entire circuit loop is abnormal by counting. The control process of the self-test control chip MCU module is the same as step 7 and step 8.

[0069] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A low-power self-checking bubble sensor based on dual-channel pulse counting, characterized in that: It includes a control chip MCU module, a double-pulse ultrasonic generation drive circuit, an ultrasonic transmitting terminal, an ultrasonic receiving terminal, a signal amplifying circuit, and a signal comparator. The control chip MCU module is connected to the double-pulse ultrasonic generation drive circuit, the double-pulse ultrasonic generation drive circuit is connected to the ultrasonic transmitting terminal, the ultrasonic transmitting terminal and the ultrasonic receiving terminal are arranged opposite to each other, the ultrasonic receiving terminal is connected to the signal amplifying circuit, the signal amplifying circuit is connected to the comparator, and the comparator is connected to the control chip MCU module.

2. According to claim 1, a low-power self-checking bubble sensor based on dual-path pulse counting is characterized in that: The double-pulse ultrasonic wave generating and driving circuit is connected to the signal amplifying circuit.

3. The low-power self-checking bubble sensor based on dual-path pulse counting according to claim 2 is characterized in that: The control chip MCU module generates an excitation pulse of 2 MHz.

4. The low-power self-checking bubble sensor based on dual-path pulse counting according to claim 2 is characterized in that: The control chip MCU module generates adjustable PWM pulses.

5. The method of a bubble sensor based on dual-path pulse counting, low power consumption and self-checking according to claim 1 is characterized in that: The steps include: S1: System startup; S2: Send out excitation pulse and shaping pulse; S3: The rising edge interrupt of the shaping pulse starts counting the excitation pulses; S4: The falling edge of the shaping pulse interrupts the reading of the number of excitation pulses; S5: Does the number of pulses exceed the threshold? If yes, go to S6; if no, go to S9; S6: no bubble counting; S7: Is the continuous no-bubble count less than the set value? If yes, go to S8; if not, go to S2; S8: Send a bubble-free message; Go to S2; S9: Bubble counting; S10: Is the continuous no-bubble count greater than or equal to the set value? If yes, go to S11; if not, go to S2; S11: Sending bubble information; S12: Stop sending pulse signals.

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