CN209400044U - A dual liquid level detection device and alarm device for murphy pots - Google Patents

Abstract

The utility model provides a kind of biliquid level detecting apparatus and warning device for black luxuriant and rich with fragrance pot, including an ink luxuriant and rich with fragrance pot, two sensors, conversion circuit, control circuits；The sensor is made of a RF transmitter, infrared absorber and two light pipes；The RF transmitter, infrared absorber are respectively placed in the light pipe of the two sides on ink luxuriant and rich with fragrance pot same level face；Sensor one is set to the top of the luxuriant and rich with fragrance pot of the ink, and sensor two is set to the lower part of the luxuriant and rich with fragrance pot of the ink, and the input terminal and output end of sensor are respectively equipped with conversion circuit；Sensor one and sensor two in the mutually perpendicular two pairs of sensors of same level respectively by constituting；Sensor exports two voltages Ve3, Ve4 in endpoint e after endpoint e output two voltages Ve1, Ve2, the converted circuit of the sensor two after conversion circuit.The technical solution of the utility model is easy to operate, accuracy is higher.

Description

A dual liquid level detection device and alarm device for murphy pots

technical field

The utility model designs a liquid level detection device, in particular to a liquid level detection device for a murphy pot.

Background technique

Intravenous infusion is one of the commonly used disease treatment methods. At present, the commonly used infusion tube is basically made of transparent plastic. The intravenous infusion line itself does not have the monitoring and alarm function. Timely processing to avoid blood return in the infusion line is a very heavy workload for medical staff, and it is also a burden for patients and their families, especially for patients, which affects their rest. Sometimes due to the carelessness or fatigue of patients and their family members, or the busy nurses who fail to make inspections in time, they cannot find the end of the liquid infusion in time, resulting in blood returning in the infusion tube or air entering the blood vessel, resulting in adverse consequences. Therefore, an additional infusion alarm is needed, and when the infusion is about to end, the infusion alarm generates an alarm signal to remind the patient and family members or medical staff.

The main types of existing liquid level detection devices include weight measurement, capacitance sensing, photoelectric sensing and other different types. Some types have complex structure, high cost, many steps to use, and cumbersome operation process; some types are designed and innovated for the infusion bag itself, which cannot be applied to all types of infusion bags, and the practicability is not high. The sensor that triggers the alarm signal is in the Sensing is carried out in the sensing area, but the sensor must be directly inserted into the infusion bottle for use, which may contaminate the liquid medicine.

Therefore, how to design a medical infusion alarm or a medical infusion alarm system with easy operation and high accuracy has become a problem to be solved at present.

Chinese Patent Application Publication No. CN 102284105A, the title of the invention is an infusion alarm device, which discloses an infusion alarm system centered on liquid level detection and a single-chip microcomputer, including a power module, a photoelectric sensor, a comparator, a single-chip microcomputer, an LED Lamp, sound alarm device and actuator; Among them, the liquid in the infusion tube is detected by a photoelectric sensor (photoelectric interrupter), and the infusion alarm system is controlled by a single-chip microcomputer; the photoelectric sensor is a photoelectric interrupter, which is used to detect the liquid in the infusion tube The comparator is a voltage comparator; when there is liquid in the infusion tube, the phototransistor of the photoelectric sensor receives stronger infrared light emitted by the infrared diode, and the current flowing through the phototransistor circuit is relatively large, so the negative voltage of the voltage comparator The voltage decreases, the output is high level, the alarm does not take any action, and the infusion continues; when the infusion is close to the end, that is, when the infusion tube has no liquid, the photosensitive triode of the photoelectric sensor receives the weak infrared light emitted by the infrared diode, The current flowing through the phototransistor circuit is small, and the current changes significantly, so the negative voltage of the voltage comparator increases, and the output is low. However, the situation is that all the liquid in the Murphy pot indicates that the infusion has failed. When the liquid in the infusion tube is detected, there is also liquid in the infusion tube. It is also necessary to notify the medical staff, but the infusion alarm device cannot alarm.

Contents of the invention

Aiming at the above defects or improvement needs of the prior art, the utility model provides a detection device in three different states, that is, the murphy pot has no liquid, is half-filled and is full of liquid.

The technical scheme of the utility model is:

A liquid level detection device for a murphy pot, comprising a murphy pot, two sensors, a conversion circuit, and a control circuit; the sensor is composed of an infrared emitter, an infrared absorber and two light guide tubes; the infrared emitter The infrared absorbers are respectively placed in the light guide tubes on both sides of the same horizontal plane of the Murphy pot;

Sensor 1 is set on the upper part of the Murphy pot, and sensor 2 is set on the lower part of the Murphy pot. Sensor 1 and sensor 2 are respectively composed of two pairs of sensors perpendicular to each other on the same horizontal plane;

The input end and the output end of the sensor are respectively provided with conversion circuits;

Sensor 1 outputs two voltages Ve1 and Ve2 at terminal e after conversion circuit, and sensor 2 outputs two voltages Ve3 and Ve4 at terminal e after conversion circuit;

The control circuit includes an A/D conversion circuit and a controller for controlling the comparison and state judgment of the four input signal values of Ve1, Ve2, Ve3 and Ve4.

Further, the above-mentioned controller is an embedded controller,

During normal infusion, the above four signals satisfy the following relationship at the same time:

a)-0.2<(Ve1-Ve2)/Ve2<0.2;

b) -0.2<(Ve3-Ve4)/Ve4<0.2;

c) -0.7>(Ve1-Ve3)/Ve3, or 0.7<(Ve1-Ve3)/Ve3;

Other conditions are abnormal, indicating that the following failures or errors have occurred:

a) The sensor is damaged;

b) The infusion has been completed.

Further, the above-mentioned infrared emitter and infrared absorber are respectively an LED light-emitting diode D1 and a phototransistor D2.

Further, the output terminal and the output terminal of the above sensor are respectively provided with a conversion circuit, and the conversion circuit includes a parallel circuit of a power supply, an LED current limiting resistor R1, a resistor (R2) and a capacitor (C1).

A double liquid level detection and alarm device for a murphy pot comprising the above double liquid level detection device, the liquid level detection device also includes an execution circuit,

When the infusion is normal, there is no need to alarm, at this time Vout>0, the buzzer does not work;

When a fault or error occurs, Vout≤0, the buzzer starts to work.

Further, the above execution circuit is two resistors and two triodes, the base b of the triode D5 is connected to one end of the resistor R7, the collector C of D5 is connected to the base b of D6, the emitter e of D5 is grounded, and the collector of D6 c is connected to the power supply VCC, the emitter e of D6 is connected to one end of the buzzer, and the two ends of the resistor R8 are respectively connected to the power supply VCC and the collector C of D5.

Generally speaking, compared with the prior art, the above technical solutions conceived by the utility model are easier to operate and have higher precision.

Description of drawings

Fig. 1 is the schematic diagram of the dual liquid level detection device of the Murphy pot of the present utility model;

Fig. 2 is a top view schematic diagram of two sensors of the same section of the dual liquid level detection device of the Murphy pot of the present invention;

Fig. 3 is the schematic diagram of conversion circuit of the present utility model;

Fig. 4 is the control circuit schematic diagram of the present utility model;

Fig. 5 is a schematic diagram of an alarm circuit of the present utility model;

Fig. 6 is a schematic diagram of the alarm process of the dual liquid level detection device of the Murphy pot of the present invention;

Fig. 7 is a schematic diagram of the ADC0809 pin structure of the utility model;

1-Murphy pot; 2-sensor; 3-conversion circuit;

21-LED light-emitting diode D1; 22-photosensitive transistor D2; 23-light guide tube;

In Figure 1, the short arrow indicates the direction of infrared rays; the long arrow of the Murphy pot indicates the direction of infrared rays in the Murphy pot.

Detailed ways

In order to make the purpose, technical solution and advantages of the utility model clearer, the utility model will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the utility model, and are not intended to limit the utility model. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not constitute conflicts with each other.

Referring to Fig. 1, a dual liquid level detection device for a Murphy pot is composed of a Murphy pot 1 and two sensors 2; 2) Place the lower part of the murphy pot 1 .

The structure of sensor 1 and sensor 2 is shown in Figure 1 below. Each pair of sensors includes an LED light-emitting diode D1, a phototransistor D2, and two light guide tubes 23; the light guide tube 23 is an opaque tubular structure, which can be opaque plastic tube and other materials.

The structure of the phototransistor is similar to that of the ordinary triode; the difference is that the phototransistor must have a light-sensitive PN junction as the photosensitive surface, and the collector junction is generally used as the light-receiving junction. Therefore, the phototransistor is essentially a kind of An ordinary triode with a photodiode connected between the base and collector. The phototransistor is the same as the ordinary semiconductor triode, it is a semiconductor tube with NPN or PNP structure made by semiconductor manufacturing process. It is similar in structure to a semiconductor triode, and its lead-out electrodes usually have only two or three. In order to meet the requirements of photoelectric conversion, the area of its base area is made larger, and the area of the emission area is made smaller, and the incident light is mainly absorbed by the base area. Like photodiodes, the chip of the tube is housed in a metal casing with a glass lens. When light is irradiated, the light is concentrated on the chip through the lens. When the PN junction with photosensitive characteristics is irradiated by light, a photocurrent is formed, and the resulting photogenerated current enters the emitter from the base, so that a signal current amplified by β times is obtained in the collector circuit.

The LED light-emitting diode is placed in the light guide tube. The function of the light guide tube is to gather the light emitted by the LED light-emitting diode; the photosensitive transistor D2 receives the light from D1 and generates an output current corresponding to the light intensity. The function of the light guide tube is Block the light from other directions, so that D2 only accepts the light from D1, thereby reducing the interference of ambient light.

The role of the sensor is to measure whether liquid is contained in the path of light propagation. The attenuation rate of light propagating in water is greater than the attenuation rate of light propagating in air, and when the light is infrared, the contrast (or distinction) of this attenuation effect is more obvious.

When the output current of sensor 1 and sensor 2 is the same or similar, it means that there are two situations in the Murphy pot of the infusion tube. One is that there is air in the Murphy pot, which means that the infusion has been completed and an alarm signal needs to be output to notify the medical staff. Another situation is that all the liquid in the Murphy pot indicates that the infusion has failed, and the medical staff also need to be notified.

When the output currents of sensor one and sensor two are significantly different, there are two situations. The first one is that the output current of sensor one is obviously smaller than the output current of sensor two, indicating that the sensor is faulty and needs to output an alarm signal for maintenance; the second case is that the output current of sensor one is obviously greater than the output current of sensor two, indicating that the ink There is liquid medicine in the Murphy pot, and the Murphy pot is not full. This situation is a normal infusion state, and no alarm signal needs to be output.

To sum up, only when the output current (output voltage) of sensor 1 > the output current (voltage) of sensor 2, no alarm is required, and the alarm is required in other cases.

Referring to Figure 2, it is a top view diagram of two sensors in the same section of the liquid level detection device of the Murphy pot; that is, there are two groups of liquid level detection devices in the Murphy pot, namely, the upper and lower groups, and the sensor one on the top. Below is sensor two.

The structure of each group of two pairs of sensors perpendicular to each other on the same horizontal plane is shown in Figure 2. Each pair of sensors includes an LED light-emitting diode D1, a photosensitive transistor D2, and two light guides; the light guide is an opaque tubular structure that can Use materials such as opaque plastic tubing.

See Figure 3, conversion circuit:

Since infusion is a slow-changing process, and the output voltage and current of the sensor are transient values, they may be falsely alarmed by external interference. In order to reduce and eliminate false alarms, a conversion circuit is needed to convert the transient value of the sensor into a stable value.

A simple conversion circuit includes a parallel circuit of a power supply, LED current limiting resistor R1, a resistor R2 and a capacitor (C1). The capacitance of the capacitor is generally relatively large, such as tens of microfarads, and the specific value is determined through experiments. The output of the conversion circuit is terminal e. Then the sensor one outputs two voltages Ve1 and Ve2 at the terminal e after the conversion circuit, and the sensor two outputs two voltages Ve3 and Ve4 at the terminal e after the conversion circuit.

See Figure 4, the control circuit:

The control circuit includes A/D conversion circuit and embedded controller. The input signal is Ve1, Ve2, Ve3, Ve4, and the output signal is the driving signal of the executive circuit.

There are many types of A/D conversion chips, and the selection criteria are mainly cost, conversion time, and the number of analog input ports. This patent does not limit in the claims, but only lists an example in the specific circuit, and the selected A/D circuit adopts the chip ADC0809. Its main parameters are as follows:

Number of analog input ports: 8

Conversion time: 128us

Output data: 8 bits

There are also many types of embedded controllers, and the chips that can be selected include C51, Z80, ARM, FPGA, X86, etc. This patent does not limit in the right item, only enumerates an example in the concrete circuit, adopts AT89C51 single-chip microcomputer.

The specific circuit diagram of the control circuit is as follows. Only the main pins and connecting wires are listed in the circuit diagram, and auxiliary pins and wiring such as power supply, clock crystal oscillator, and reset are not listed.

See the appendix for the specific description of the ADC0809 chip

See Figure 5, the execution circuit:

The executive circuit can take various forms, and its main purpose is to send out various signals, such as lights and sounds, to remind patients and their families, or medical staff.

The executive circuit consists of two resistors and two triodes, the base b of the triode D5 is connected to one end of the resistor R7, the collector C of D5 is connected to the base b of D6, the emitter e of D5 is grounded, and the collector c of D6 is connected to the power supply VCC , the emitter e of D6 is connected to one end of the buzzer, and the two ends of the resistor R8 are respectively connected to the power supply VCC and the collector C of D5. In the figure, resistor R7 limits the base current of D5 within the allowable range to reduce power consumption, and resistor R8 limits the transistor current during the conduction period of D5 within the allowable range to reduce power consumption.

Ve1 and Ve2 are mutual backups, Ve3 and Ve4 are mutual backups, the comparison and state judgment of the four input signal values of Ve1, Ve2, Ve3, Ve4 are as follows.

1. During normal infusion, the above four signals satisfy the following relationship at the same time:

a)-0.2<(Ve1-Ve2)/Ve2<0.2;

b) -0.2<(Ve3-Ve4)/Ve4<0.2;

c) -0.7>(Ve1-Ve3)/Ve3, or 0.7<(Ve1-Ve3)/Ve3;

Note: The above-mentioned values of -0.7, -0.2, 0.2, 0.7 are examples, and the specific values are determined according to the test.

2. Other conditions are abnormal, indicating that the following failures or errors occur, and the alarm needs to be reported:

a) The sensor is damaged;

b) The infusion has been completed.

Supplementary note:

VCC in all circuits is the same supply; ground in all circuits is the same ground.

See Figure 6, flow chart:

The overall design of the system is shown below. Including sensor, conversion circuit, comparison circuit, execution circuit and other functional modules.

Sensor 1 and sensor 2 measure different positions and output current; the output current of the sensor is converted into the positive voltage or zero voltage of the logic circuit through the conversion circuit; the positive voltage or zero voltage output by the conversion circuit is input into the comparison circuit, and the logic circuit of the comparison circuit After calculating and outputting the control model, the control execution circuit completes the corresponding action.

See Figure 7, ADC0809 pin structure function description diagram:

1~5, 26~28, IN0~IN7: 8 analog input terminals.

14~15, 8, 17~21, D0~D7: 8-bit digital output terminals.

23~25, ADDA, ADDB, ADDC: 3-bit address input line, used to select one of the 8 analog inputs

22. ALE: address latch enable signal, input, high level active, corresponding to the rising edge of ALE, A, B, C address status is sent to the address latch.

6. START: A/D conversion start signal, input high level is active, reset ADC0809 when START rises; start the chip when START falls, and start A/D conversion; during A/D conversion, START should be kept low level. This signal is sometimes abbreviated as ST.

7. EOC: A/D conversion end signal, output, when A/D conversion ends, this terminal outputs a high level (always low level during conversion).

9. OE: Data output enable signal, input, active high. When the A/D conversion is over, input a high level at this terminal to open the output tri-state gate and output digital quantity, which is used to control the tri-state output latch to output the converted data to the microcontroller. OE=0, the output data line is high resistance; OE=1, the converted data is output.

10. CLK: clock pulse input terminal. It is required that the clock frequency is not higher than 640KHZ, EOC=0, the conversion is in progress; EOC=1, the conversion is completed. In use, the status signal can be used as a status flag for inquiry, and can also be used as an interrupt request signal.

12, 16, REF(+), REF(-): Reference voltage.

11. Vcc: power supply, single +5V.

13. GND: ground.

Specifically, sensor one and sensor two measure different positions and output current; the output current of the sensor is converted into positive voltage or zero voltage of the logic circuit through the conversion circuit; the positive voltage or zero voltage output by the conversion circuit is input into the comparison circuit, and the comparison circuit The logic circuit outputs the control model after calculation, and the control execution circuit completes the corresponding action of alarm or non-alarm.

Claims (6)

1. a kind of biliquid level detecting apparatus for black luxuriant and rich with fragrance pot, including an ink luxuriant and rich with fragrance pot, two sensors, conversion circuit, controls Circuit；The sensor is made of a RF transmitter, infrared absorber and two light pipes；The infrared ray transmitting Device, infrared absorber are respectively placed in the light pipe of the two sides on ink luxuriant and rich with fragrance pot same level face；

It is characterized in that, sensor one is set to the top of the luxuriant and rich with fragrance pot of the ink, sensor two is set to the lower part of the luxuriant and rich with fragrance pot of the ink,

The sensor one and sensor two in the mutually perpendicular two pairs of sensors of same level respectively by constituting；

The input terminal and output end of the sensor are respectively equipped with conversion circuit；

The sensor exports two voltages Ve1, Ve2, the converted circuit of the sensor two in endpoint e after conversion circuit Two voltages Ve3, Ve4 are exported in endpoint e afterwards；

The control circuit is including an A/D conversion circuit and for controlling tetra- input signal numerical value of Ve1, Ve2, Ve3, Ve4 Comparison and state judgement controller.

2. biliquid level detecting apparatus as described in claim 1, which is characterized in that the controller is embedded controller,

When normal infusion, aforementioned four signal meets following relationship simultaneously:

a)-0.2<(Ve1-Ve2)/Ve2<0.2;

b)-0.2<(Ve3-Ve4)/Ve4<0.2;

C) -0.7>(Ve1-Ve3)/Ve3 or 0.7<(Ve1-Ve3)/Ve3;

Other situations are abnormal condition, illustrate that following failure or mistake occurs:

A) sensor degradation；

B) infusion has been completed.

3. biliquid level detecting apparatus as described in claim 1, which is characterized in that the RF transmitter, infrared absorber An a respectively LED light emitting diode D1 and phototriode D2.

4. biliquid level detecting apparatus as described in claim 1, which is characterized in that the conversion circuit includes power supply, LED current limliting A resistance R1 and resistance R2 and capacitor C1 parallel circuit.

5. a kind of including being used for the luxuriant and rich with fragrance pot of ink for the biliquid level detecting apparatus of the luxuriant and rich with fragrance pot of ink described in claims 1 or 2 or 3 or 4 Double liquid level detect warning device, which is characterized in that the liquid level detection device further includes an execution circuit,

It when normal infusion, does not need to alarm, at this time Vout > 0, buzzer does not work；

When breaking down or being wrong, Vout≤0, buzzer is started to work.

6. double liquid level as claimed in claim 5 detects warning device, which is characterized in that the execution circuit be two resistance and Two triodes, one end of the base stage b connection resistance R7 of triode D5, the base stage b, D5 of the collector C connection D6 of D5 Emitter e ground connection, the emitter e of collector c connection the power supply VCC, D6 of D6 connects one end of buzzer, resistance R8 Both ends be separately connected the collector C of the power supply VCC and D5.