CN108478902A - A flow detection device of a medical infusion pump quality detector - Google Patents

Abstract

The invention relates to a flow detection device of a medical infusion pump quality detector, which comprises a controller, two infusion systems and a liquid supply system, wherein the two infusion systems are arranged, the infusion systems are connected with a liquid storage tank through infusion pipelines, a first one-way valve and a second one-way valve are arranged in the pipelines, the infusion systems can output and suck liquid periodically, the liquid suction time and the liquid output time of the infusion systems are the same, the liquid suction time or the liquid output time of the infusion systems are all in a uniform speed state, and the phase difference of the relation curves of the liquid flow and the time of the two infusion systems is half a period. The device can provide test liquid for the medical infusion pump quality detector in an unlimited way by outputting the liquid flow with small pulsation and high precision, and has stable and reliable work.

Description

A flow detection device of a medical infusion pump quality detector

technical field

The invention relates to the field of medical detection equipment, in particular to a flow detection device for a medical infusion pump quality detector.

Background technique

Infusion pumps and syringe pumps are instruments that control the flow rate of infusion and injection through electronic control devices and mechanical devices. They are often used to achieve high-precision, stable and non-pulsating liquid transmission, and the quantitative liquid medicine is accurate, small, uniform and continuous. It can be pumped into the human body to maintain the effective blood concentration of the drug in the body, rescue critically ill patients, improve the efficiency and flexibility of clinical drug administration operations, and reduce the workload of nursing.

Infusion pumps and syringe pumps are medical devices with a high risk level in clinical use. Human error operation or equipment performance problems will cause serious medical accidents. At present, there are a large number of infusion pump machines used clinically in my country, and the number is growing rapidly. According to data, by 2010, the number of infusion pumps and injection pumps equipped with various medical machinery in my country has exceeded 200,000 units, and the annual growth rate has exceeded 35%. Therefore, the quality and safety of infusion pumps is particularly important. Use the infusion pump quality detector to regularly measure the infusion pumps and syringe pumps to ensure the safe use of infusion pumps in hospitals.

In clinical use, the commonly used flow output range of infusion pumps is 5~150ml/h, which belongs to the measurement range of small flow, and it is difficult to measure this flow range. At present, one method of micro-flow calibration for infusion pump quality detectors is by weighing method. The calibration process requires high-precision electronic stopwatches, electronic balances and volumetric bottles. The flow is calculated by measuring the weight of the liquid flowing out within a period of time. Although this method is simple, it requires a constant temperature and humidity operating environment, the evaporation of liquid, the measurement accuracy of time interval measurement, etc. are important factors affecting the flow measurement results, the condition requirements are relatively high, and there are many factors affecting the measurement accuracy.

Another method is to use a high-precision syringe pump, and a high-precision stepping motor drives the liquid output, such as the PHD22/2000 precision syringe pump produced by Harvard Apparatus, which will provide a stable flow source through the high-precision syringe pump , Disadvantages: The volume of the syringe is limited, and the liquid must be re-added after each injection of the liquid in the syringe. The state after re-adding the liquid may not be exactly the same as the previous one.

When performing quality inspection on syringe pumps, a syringe pump quality detector with high precision is required. When calibrating the syringe pump quality detector, a calibration instrument that can provide stability and little interference is required. Through the small output pulsation, the precision High liquid flow enables calibration of syringe pump quality detectors.

Contents of the invention

The technical problem to be solved by the present invention is to provide a flow detection device for a medical infusion pump quality detector, which can output liquid flow with small pulsation and high precision, and its performance is stable and reliable. In the state of little interference and low cost of use, a calibration result as close as possible to the standard value can be obtained, and the application area is relatively wide.

In order to solve the problems of the technologies described above, the technical solution adopted in the present invention is:

A flow detection device for a medical infusion pump quality detector, characterized in that it includes a controller, an infusion system and a liquid supply system, the infusion system is provided with two groups, and the infusion end of the infusion system is connected with an infusion pipeline , the infusion pipeline is provided with a first one-way valve, the conduction direction of the first one-way valve is consistent with the infusion direction of the infusion system, and the infusion pipeline is connected to one end of the suction pipeline, so The connection between the suction pipeline and the infusion pipeline is set between the infusion end of the infusion system and the first one-way valve, the other end of the suction pipeline is connected to the liquid storage tank, and the suction pipeline is provided with The second one-way valve, when the liquid flows from the liquid storage tank to the infusion line, the second one-way valve conducts;

The infusion system can periodically output and inhale liquid, the inhalation time of the infusion system is the same as the time for output liquid, the infusion system inhales liquid or the output liquid is in a constant state, the two groups of infusion systems The liquid flow versus time curves are out of phase by half a cycle.

In order to optimize the above invention, the specific measures taken also include:

The infusion system includes a driver, the signal input end of the driver is connected to the signal control of the driver, the signal output end of the driver is connected to the signal control of the stepping motor, and the output shaft of the stepping motor is connected to the camshaft for transmission , the camshaft is fixedly mounted with a cam, the cam is connected to the piston rod in transmission, and the end of the piston rod away from the cam is fixedly equipped with a sealing piston, and the sealing piston is arranged in the micropump. When the camshaft rotates, the piston rod can be driven to slide in the axial direction of the piston rod, thereby controlling the micropump to suck or output liquid.

The end of the piston rod close to the cam is fixed with a driven wheel, the driven wheel can rotate freely around the axis, the side of the driven wheel is in contact with the side of the cam, and the piston rod is provided with an elastic return Position mechanism, the elastic return mechanism can ensure the contact of the driven wheel and the cam.

The elastic return mechanism includes a spring, the spring is sleeved on the piston rod, one end of the spring is fixed on the baffle, and the other end is fixed on the piston rod handle, and the baffle is fixed on the miniature At the tail of the pump, the piston rod handle is fixedly installed at the end of the piston rod, and the spring is in a compressed state.

The camshaft is eccentrically arranged in the cam.

The liquid flow versus time curve of the infusion system is a square wave.

The specifications of the first one-way valve and the second one-way valve are the same, that is, the flow rate after conduction is the same, and the material and inner diameter of the suction pipeline and the infusion pipeline are the same.

The beneficial effects that the flow detection device of the medical infusion pump quality detector can achieve are as follows:

First, the two sets of infusion systems absorb and infuse alternately, which ensures the continuity of the infusion state and the continuous infusion volume, which reduces the trouble of replacing the infusion pump body many times in traditional infusion pumps.

Second, the two sets of infusion systems can use the same set of power systems to ensure that the infusion cycles of the two sets of infusion systems are the same and the infusion status is constant with a difference of half a cycle.

Third, the controller controls the number of revolutions of the stepping motor to control the infusion volume of the infusion, so that the infusion volume can be accurately detected.

Fourth, the elastic return mechanism arranged around the piston rod can press the driven wheel tightly so that it is in close contact with the cam, ensuring that the piston can move stably with the rotation of the cam.

Fifth, the calibration of the syringe pump quality detector is realized by outputting liquid flow with small pulsation and high precision, and at the same time, any volume of liquid can be output according to demand.

Description of drawings

Fig. 1 is a structural principle diagram of a flow detection device of a medical infusion pump quality detector according to the present invention.

Fig. 2 is a graph showing the relationship between flow rate and time when a single infusion system supplies liquid in a flow detection device of a medical infusion pump quality detector according to the present invention.

Fig. 3 is a graph showing the relationship between flow rate and time when the two groups of infusion systems supply liquid in a flow detection device of a medical infusion pump quality detector according to the present invention.

Legend: 1. Controller; 2. Driver; 3. Stepping motor; 4. Cam; 5. Camshaft; 6. Micro pump; 7. Piston rod; 8. Driven wheel; 9. Spring; 10. Piston rod Handle; 11, baffle; 12, first one-way valve; 13, second one-way valve; 14, liquid storage tank; 15, suction pipeline; 16, infusion pipeline.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings and specific preferred embodiments.

A kind of medical infusion pump quality detector flow detection device as shown in Figure 1, comprises controller 1, infusion system and liquid supply system, described infusion system is provided with two groups, and the infusion end of described infusion system is connected with An infusion line 16, the infusion line 16 is provided with a first one-way valve 12, the conduction direction of the first one-way valve 12 is consistent with the infusion direction of the infusion system, and the infusion line 16 and One end of the suction pipeline 15 is connected, and the connection between the suction pipeline 15 and the infusion pipeline 16 is set between the infusion end of the infusion system and the first one-way valve 12, and the other end of the suction pipeline 15 is connected to the liquid storage. The tank 14 is connected, and a second one-way valve 13 is arranged in the liquid suction pipeline 15. When the liquid flows from the liquid storage tank 14 to the infusion pipeline 16, the second one-way valve 13 conducts;

The infusion system can periodically output and inhale liquid, the inhalation time of the infusion system is the same as the time for output liquid, the infusion system inhales liquid or the output liquid is in a constant state, the two groups of infusion systems The liquid flow versus time curves are out of phase by half a cycle.

In this embodiment, the infusion system includes a driver 2, the signal input end of the driver 2 is connected to the signal control of the driver 1, the signal output end of the driver 2 is connected to the signal control of the stepping motor 3, and the stepping motor 3 The output shaft of the output shaft is connected with the camshaft 5 in transmission, the camshaft 5 is fixedly installed with the cam 4, the cam 4 is connected with the piston rod 7 in transmission, and the end of the piston rod 7 away from the cam 4 is fixedly installed with a sealing piston , the sealing piston is arranged in the micropump 6, and the camshaft 5 can drive the piston rod 7 to slide in the axial direction of the piston rod 7 when the camshaft 5 rotates, thereby controlling the micropump to suck or output liquid.

In this embodiment, a driven wheel 8 is fixedly mounted on the end of the piston rod 7 close to the cam 4. The driven wheel 8 can rotate freely around the axis, and the side of the driven wheel 8 is in contact with the side of the cam 4. The piston rod 7 is provided with an elastic return mechanism, and the elastic return mechanism can ensure the contact between the driven wheel 8 and the cam 4 .

In this embodiment, the elastic return mechanism includes a spring 9, the spring 9 is sleeved on the piston rod 7, and one end of the spring 9 is fixed on the baffle 11; the other end is fixedly installed on the piston rod handle 10, The baffle plate 11 is fixedly mounted on the tail of the micropump 6, the piston rod handle 10 is fixedly mounted on the tail end of the piston rod 7, and the spring 9 is in a compressed state.

In this embodiment, the camshaft 5 is eccentrically arranged inside the cam 4 .

In this embodiment, the specifications of the first one-way valve 12 and the second one-way valve 13 are the same, that is, the flow rate after conduction is the same, and the material and inner diameter of the suction pipeline 15 and the infusion pipeline 16 are the same.

In this embodiment, the output flow range of the detection device of the medical infusion pump quality detector is 1ml/h~1000ml/h, and the capacity of each micropump is 200ul.

In this embodiment, the controller 1 also sends a drive command to the driver 2, so that the stepper motor 3 drives the camshaft 5 to rotate, thereby driving the cam 4 to rotate, and the driven wheel 8 rotates after being rubbed by the cam 4. When the piston is in the return motion At this time, due to the effect of the piston rod handle 10 and the micropump baffle plate 11, and the weakening of the applied pressure, the spring 9 gradually stretches out, and the piston rod 7 moves to the left. Due to the first check valve 12, the second check valve 13 The effect of micropump 6 begins to suck liquid from liquid storage tank 14 li. When the piston is in process movement, the micropump 6 expels liquid outwards.

Because the two micropumps 6 are all in different strokes all the time, when one micropump 6 just ends the liquid stroke, the other micropump 6 just completes the liquid storage stroke. The pump 6 is transferred to the liquid discharge stroke, and the other micropump 6 is transferred to the liquid storage stroke. In this way, a stable and small precision flow with little fluctuation can be output in the form of complementary alternation.

The relationship curve of the discharge flow rate and time of a single micro pump discharge is shown in Figure 2, and the relationship curve of the discharge flow rate and time of the combined discharge of two micro pumps is shown in Figure 3.

When the design capacity of each micropump is 200ul, and the set flow rate is Q (ml/h), the number of liquid discharge strokes N required within an hour is shown in formula (1):

N=Q/0.2 Formula (1)

Then each micropump requires a liquid discharge stroke of 1/2N per hour, and within each liquid discharge stroke, it is only necessary to control the liquid to be discharged evenly. This method can quickly detect the flow rate of the infusion pump.

A single set of micropumps will be in the liquid suction stage for a period of time in each cycle, and the output flow is zero. Therefore, two sets of micropumps are used to form a complementary structure, and the liquid storage and liquid discharge strokes are completed alternately in each cycle. Thereby avoiding the zero flow situation within a certain period of time and reducing the pulsation of the output waveform.

The above are only preferred implementations of the present invention, and the protection scope of the present invention is not limited to the above-mentioned embodiments, and all technical solutions under the idea of the present invention belong to the protection scope of the present invention. It should be pointed out that for those skilled in the art, some improvements and modifications without departing from the principle of the present invention should be regarded as the protection scope of the present invention.

Claims (7)

1. a kind of infusion pump in medical application mass detecting instrument flow detector, it is characterized in that：Including controller（1）, transfusion system with And liquid-supplying system, the transfusion system are provided with two groups, the infusion end of the transfusion system is connected with infusion pipeline（16）, The infusion pipeline（16）Inside it is provided with the first check valve（12）, first check valve（12）Conducting direction and infusion Consistent, the described infusion pipeline in system infusion direction（16）With imbibition pipeline（15）One end is connected to, the imbibition pipeline（15） With infusion pipeline（16）Connectivity part setting in transfusion system infusion end and the first check valve（12）Between, imbibition pipeline（15）Separately One end and fluid reservoir（14）Connection, the imbibition pipeline（15）Inside it is provided with the second check valve（13）, when liquid is from fluid reservoir （14）Flow to infusion pipeline（16）When, the second check valve（13）Conducting；

The transfusion system can export periodically, suck liquid, and the transfusion system sucks time of liquid and defeated The time for going out liquid is identical, and transfusion system sucking liquid or output liquid are at the uniform velocity state, two groups of transfusion systems Fluid flow differs half period with the phase of the relation curve of time.

2. a kind of infusion pump in medical application mass detecting instrument flow detector according to claim 1, it is characterised in that：It is described Transfusion system include driver（2）, the driver（2）Signal input part and driver（1）Signal control connection, it is described Driver（2）Signal output end and stepper motor（3）Signal control connection, the stepper motor（3）Output shaft with it is convex Wheel shaft（5）It is sequentially connected, the camshaft（5）Cam is fixedly mounted in fixation（4）, the cam（4）With piston rod（7） It is sequentially connected, the piston rod（7）Far from cam（4）One end is installed with sealing piston, sealing piston setting In micropump（6）Interior, described camshaft（5）Piston rod can be driven when rotation（7）In piston rod（7）Axis upward sliding, And then control micropump sucking or output liquid.

3. a kind of infusion pump in medical application mass detecting instrument flow detector according to claim 2, it is characterised in that：It is described Piston rod（7）Close to cam（4）One end is installed with driven wheel（8）, the driven wheel（8）Can freely it turn around axle center Dynamic, described driven wheel（8）Side and cam（4）Side connect, the piston rod（7）Flexible time of upper setting Position mechanism, the elastic recoil mechanism can ensure driven wheel（8）With cam（4）Contact.

4. a kind of infusion pump in medical application mass detecting instrument flow detector according to claim 3, it is characterised in that：It is described Elastic recoil mechanism include spring（9）, the spring（9）It is sleeved on piston rod（7）On, the spring（9）One end is fixed In baffle（11）On,；The other end is fixedly mounted on piston rod handle（10）On, the baffle（11）It is fixedly mounted on micropump （6）Tail portion, the piston rod handle（10）It is fixedly mounted on piston rod（7）Tail end, the spring（9）In compressive state.

5. a kind of infusion pump in medical application mass detecting instrument flow detector according to claim 2, it is characterised in that：It is described Camshaft（5）It is eccentrically set on cam（4）It is interior.

6. a kind of infusion pump in medical application mass detecting instrument flow detector according to claim 1, it is characterised in that：It is described Fluid flow and the time curve of transfusion system be square wave.

7. a kind of infusion pump in medical application mass detecting instrument flow detector according to claim 1, it is characterised in that：It is described The first check valve（12）With the second check valve（13）Specification is identical, that is, identical, the described imbibition pipeline of flow after being connected（15） With infusion pipeline（16）Material and internal diameter size are identical.