CN103977477A - Laser micro-flow automatic control device - Google Patents

Abstract

The invention relates to a laser micro-flow automatic control device, belonging to the field of micro-flow automatic control technology. In order to realize the automatic control of the flow of the micro-flow liquid, the invention adopts the following measures: a laser transmitting tube and a laser receiving head are respectively arranged on two sides of the transparent drip chamber, the laser transmitting tube is connected with a laser signal generator, the laser receiving head is connected with a laser signal processing circuit, the laser signal processing circuit is connected with a single chip microcomputer, the single chip microcomputer is connected with a keyboard, a display screen and a driving circuit, and the driving circuit is connected with an electromagnet or a motor in the electric mechanical flow control device; the invention has the advantages that: the device is internally provided with an electromechanical flow control device, and the single chip microcomputer can compare the time distance between two drops of liquid with the set time distance and implement accurate control on the flow of the liquid in the rubber pipe through the electromechanical flow control device.

Description

Laser micro-flow automatic control device

technical field

The invention belongs to the field of micro flow automatic control technology.

Background technique

In many technical fields such as chemical automatic control, medical treatment, laboratory, etc., flow detection and long-term automatic control of micro-flow liquids are required. However, due to the micro-flow rate, its flow rate is very slow, the flow rate per unit time is very small, and its flow force is not even enough to drive the instrument to operate. Therefore, it is almost impossible to detect and measure it accurately by existing conventional technical means. Detection and measurement are the basis of automatic control, and there is no automatic control without detection and measurement. In the above-mentioned special occasions, most of them can only adopt the traditional methods of artificial empirical measurement and manual control at present. However, due to the low accuracy and poor stability of manual empirical measurement and manual control, it is often necessary to monitor for a long time manually, which greatly increases the labor intensity of workers and the probability of error. In these occasions, it is especially necessary to detect and measure the micro-flow liquid medicine, and at the same time, it is necessary to carry out precise automatic control technology, so as to reduce the labor intensity of workers and reduce the probability of error.

On the other hand, the flowmeters used in the prior art are not only unable to measure the micro-flow rate of the liquid medicine, but they all need the liquid medicine to be metered to flow through the flowmeter, which is easy to cause pollution of the liquid medicine and corrosion of the flowmeter and other damage. Not allowed for medical use. Therefore, in the prior art, no suitable micro-flow detection and automatic control device can be found in technical fields such as medical treatment.

Contents of the invention

In order to realize automatic control of the flow rate of the micro-flow liquid, the present invention takes the following measures: a laser emitting tube and a laser receiving head are respectively installed on both sides of the transparent drip tube, the laser emitting tube is connected to the laser signal generator, and the laser receiving head is connected to the laser signal generator. Processing circuit, the laser signal processing circuit is connected to the single-chip microcomputer, the single-chip computer is connected to the keyboard, the display screen and the driving circuit, and the driving circuit is connected to the electromagnet or the motor in the electromechanical flow control device; the laser signal processing circuit mentioned here means that it can receive laser light Outputted by the head, the electrical signal generated when the water drop flows through the transparent drip tube is converted into a circuit device that can be recognized by the single-chip microcomputer; the electromechanical flow control device mentioned here refers to the use of a motor or an electromagnet to drive a mechanical device to control the rubber hose. An electromechanical device with the size of the liquid flow in it.

The advantage of this is that the laser micro-flow automatic control device of the present invention adopts the laser detection method to detect the micro-flow of the liquid, and the detection device is non-contact to the liquid to be detected when detecting the liquid flow. In this way, the secondary pollution to the liquid to be tested can be avoided, and the corrosion and deposition of the liquid to the instrument can also be avoided; on the other hand, the device is equipped with an electromechanical flow control device. The single-chip microcomputer can compare the time distance between two drops of liquid with the set time distance, and use the comparison result to control the electromechanical flow control device. The electromechanical flow control device can precisely control the flow of the liquid in the hose, so that it Meet the set requirements, thus realizing the automatic control of the liquid micro-flow.

Description of drawings

Figure 1 is a schematic diagram of the external structure of a laser micro-flow automatic control device using electromagnetic power.

Fig. 2 is a schematic diagram of the internal structure of the laser micro-flow automatic control device using electromagnetic power.

Fig. 3 is a schematic diagram of the external structure of the laser micro-flow automatic control device powered by a motor.

Fig. 4 is a schematic diagram of the internal structure of the laser micro-flow automatic control device powered by a motor.

In the figure: laser emitting tube 1, transparent drip tube 2, stigma 3, pressing arm 4, rubber hose 5, iron core 6, keyboard 7, base 8, display screen 9, laser receiving head 10, fixed hook 11, slider 12, Screw rod 13, motor 14, electromagnet 15.

Detailed ways

In order to be able to realize automatic control of the flow of the micro-flow liquid, the present invention adopts the following structure: a laser emitting tube 1 and a laser receiving head 10 are respectively installed on both sides of the transparent drip tube 2, the laser emitting tube 1 is connected to the laser signal generator, and the laser receiving The head 10 is connected to the laser signal processing circuit, the laser signal processing circuit is connected to the single-chip microcomputer, the single-chip microcomputer is connected to the keyboard 7, the display screen 9 and the driving circuit, and the driving circuit is connected to the electromagnet 15 or the motor 14 in the electromechanical flow control device.

In order to realize automatic flow control of micro-flow, it is first necessary to be able to detect the flow of the controlled liquid. For this reason, the present invention adopts a laser micro-flow detection device. The structure of the laser micro-flow detection device is: a laser emitting tube and a laser receiving head are respectively installed on both sides of the transparent drip tube, the laser emitting tube is connected to the laser signal generator, the laser receiving head is connected to the laser signal processing circuit, and the laser signal processing circuit is connected to the single-chip microcomputer. The microcontroller is connected to the keyboard and display screen, as shown in Figure 1. The laser signal processing circuit described here refers to the circuit device that can output the laser receiving head, and the electrical signal generated when the water drop flows through the transparent drip tube, and convert it into an electrical signal that can be recognized by the single-chip microcomputer; There is no special requirement, there are various forms of laser signal processing circuits, they can have different structures and different combinations, and they are all suitable for use in the present invention.

On the other hand, the driving circuit mentioned in this application refers to a circuit that can control the magnitude of the pulling force of the electromagnet in the electromechanical flow control device or drive the forward and reverse rotation of the motor and its rotation amount according to the instructions of the single-chip microcomputer. Since the present invention has no special requirements on the driving circuit, there are various forms and structures of the driving circuit that can be used.

The electromechanical flow control device mentioned here refers to an electromechanical device that can use an electromagnet or a motor to drive a mechanical device to control the flow rate of the liquid in the rubber hose. There are various forms and structures of mechanical devices that can be used in the electromechanical flow control device, and they have different structures and different combinations. At the same time, each structure and combined form can be driven by electromagnetic or motor, and they are all suitable for use in the present invention.

This embodiment takes the automatic control of lifting needles as an example to illustrate the implementation and working principle of the present invention. To realize the automatic control of the flow rate of the injection needle, the key is to be able to detect the actual micro-flow of the liquid medicine (the number of drops per minute) during the injection injection, and at the same time, according to the difference between the actual flow rate and the set flow rate, it can be controlled by the electromechanical flow control device Actual flow, so that it matches the set flow.

Example 1, the electromechanical flow control device of this example is mainly composed of a column head 3 , a pressing arm 4 , a base 8 , an iron core 6 , and an electromagnet 15 . The column head 3 and the base 8 are fixedly installed on the casing, one end of the pressing arm 4 is movably installed on the column head 3, and the other end is movably installed on the iron core 6, which is a part of the electromagnet 15, as shown in Figure 1 and As shown in Figure 2; first hang the medicine bottle on the hook, connect the drip tube, clamp the transparent drip tube 2 between the laser emitting tube 1 and the laser receiving head 10, and then clamp the rubber tube 5 between the pressing arm 4 and the base 8, as shown in Figure 1. The electromagnet 15 is driven by the driving circuit, and the iron core 6 will generate a pulling force to pull the pressing arm 4 . The pressing arm 4 is pressed against the rubber hose 5 to control the opening of the rubber hose 5 , that is, the flow area, thereby controlling the flow of liquid in the rubber hose. After the nurse let go the air in the sebific tube 5 and connected the needle to the patient's venous blood vessel, at this moment the medicinal liquid began to drip down from the top of the transparent drip tube 2 . Turn on the power switch of the device, and after inputting the required flow to the single chip microcomputer through the keyboard 7, the circuit starts to work. When the liquid medicine droplet drops from the top of the transparent drip tube 2, the droplet flows through the emitting path of the laser, and when the laser light hits the droplet, the droplet causes the scattering and refraction of the laser light. It deflects and refracts the laser light that originally passes through the transparent drip tube 2 and reaches the laser receiving head, and its energy is greatly reduced. The reduction of laser energy reaching the laser receiving head changes the electrical signal output by the laser receiving head. These changes can truly and accurately reflect the flow of droplets. The laser receiving head is connected with a laser signal processing circuit, and the laser signal processing circuit is connected with a single-chip microcomputer. The laser signal processing circuit converts the electrical signal output by the laser receiving head into an electrical signal that can be recognized by the single-chip microcomputer, which represents the pulse electrical signal that the water droplet flows through, and then sends it to the single-chip microcomputer. According to the established procedure, the single-chip microcomputer calculates the number of drops per minute according to the time distance between the two droplets and displays it through the display screen 9 . Simultaneously, the single-chip microcomputer compares the current flow rate with the set flow rate, and controls the current intensity passing through the electromagnet 15 through the driving circuit according to the comparison result. Its working process is: if the current flow rate is greater than the set flow rate, the single-chip microcomputer increases the driving current of the electromagnet 15 through the drive circuit, so that the iron core 6 generates a greater pulling force and compresses the rubber hose 5 through the pressing arm 4. The flow area of the rubber tube 5 is reduced, so that the flow rate of the liquid is also reduced. If the current flow rate is less than the set flow rate, the above process is reversed to increase the flow area of the hose. This process can automatically adjust the current actual flow to the set flow, and the whole process is automatically controlled, thereby greatly reducing the labor intensity of nurses. On the other hand, the single-chip microcomputer can set the alarm program. For example, when the flow is not detected within a certain period of time, it can be considered that the rubber hose is blocked by pressure or the liquid medicine is finished, and the single-chip microcomputer can immediately start the alarm program and send the alarm to the nurse for processing.

Example 2, the electromechanical flow control device of this example is mainly composed of a fixed hook 11, a slider 12, a screw 13, a motor 14, gears and the like. Fixed hook 11 is fixedly installed on the casing, has a square hole on its corresponding casing. One end of the slide block 12 passes through the square hole and the fixed hook 11 clamps the rubber hose 5 together. The other end of the slider 12 is processed with an internal thread and is screwed together with the screw rod 13 . The screw rod 13 is equipped with a gear and is combined with the gear teeth on the motor, as shown in Figure 3 and Figure 4; hang the medicine bottle on the hook, connect the drip hose, and clamp the transparent drip tube 2 on the laser emitting tube 1 and the laser receiving head 10. Then clamp the rubber hose 5 between the fixed hook 11 and the slider 12, as shown in Figure 3 . When the motor rotates, the gear can drive the screw to rotate. The rotating screw rod drives the slide block 12 to move axially through threads, and the rubber hose 5 is compressed or loosened. After the nurse let go the air in the sebific tube 5 and connected the needle to the patient's venous blood vessel, at this moment the medicinal liquid began to drip down from the top of the transparent drip tube 2 . Turn on the power switch of the device, input the required flow data to the single-chip microcomputer through the keyboard 7, and after setting the required flow, the circuit starts to work. When the liquid medicine drops from the top of the transparent drip tube 2, the water droplets flow through the emission path of the laser light. When the laser light hits the water droplets, the water droplets cause the scattering and refraction of the laser light. It deflects and refracts the laser light that originally passes through the transparent drip tube 2 and reaches the laser receiving head 10, so that its energy is greatly reduced. The reduction of the laser energy reaching the laser receiving head 10 changes the electrical signal output by the laser receiving head. These changes can truly and accurately reflect the flow of droplets. The laser receiving head is connected with a laser signal processing circuit, and the laser signal processing circuit is connected with a single-chip microcomputer. The laser signal processing circuit converts the electrical signal output by the laser receiving head into an electrical signal that can be recognized by the single-chip microcomputer, which represents the pulse electrical signal that the water droplet flows through, and then sends it to the single-chip microcomputer. The single-chip microcomputer calculates the number of drops per minute (the current flow rate) according to the established program and according to the time distance between the two droplets, and displays it through the display screen 9 . The single-chip microcomputer compares the current flow rate with the set flow rate. If the current flow rate is greater than the set flow rate, the single-chip microcomputer drives the motor 14, the screw rod 13 and the slide block 12 to move in the direction of compressing the rubber hose 5 through the drive circuit. The flow area of the hose 5 is reduced. The liquid flow rate in the sebific tube 5 also reduces thereupon. If the current flow rate is less than the set flow rate, the above process is reversed, the flow area in the rubber hose 5 increases, and the flow rate also increases. This process enables the current actual flow to be automatically adjusted to the set flow. This greatly reduces the labor intensity of nurses. On the other hand, the single-chip microcomputer can set the alarm program. For example, when the flow is not detected within a certain period of time, it can be considered that the rubber hose is blocked by pressure or the liquid medicine is finished, and the single-chip microcomputer can immediately start the alarm program and send the alarm to the nurse for handling.

Claims (1)

1. The laser micro-flow automatic control device is characterized in that: the laser emitting tube (1) and the laser receiving head (10) are respectively installed on both sides of the transparent drip tube (2), and the laser emitting tube (1) is connected to the laser signal generator. The laser receiving head (10) is connected to the laser signal processing circuit, the laser signal processing circuit is connected to the single-chip microcomputer, the single-chip microcomputer is connected to the keyboard (7), the display screen (9) and the driving circuit, and the driving circuit is connected to the electromagnet (15) in the electromechanical flow control device Or motor (14); The laser signal processing circuit described here refers to the circuit device that can output the laser receiving head, and the electric signal generated when the water drop flows through the transparent drip tube into an electric signal that can be recognized by the single-chip microcomputer; The electromechanical flow control device mentioned above refers to an electromechanical device that uses a motor or an electromagnet to drive a mechanical device to control the flow rate of the liquid in the rubber hose.