Development of multi-functional sampling refrigeration incubator

Development of multi-functional sampling refrigeration incubator

(Abstract) Design the functions of sampling, refrigerating, incubator and solar power supply into one. The box is equipped with high-efficiency composite heating, cooling and temperature control devices. The computer automatically controls the sampling, refrigerating and cultivating the required temperature. The functions of the refrigerating and incubator are common, so that the number of carrying boxes can be reduced, the weight can be reduced, and the utility model can be operated without depending on the mains, which is particularly suitable for use in field conditions.

In the anti-terrorism and anti-virus weapons attack, the sampling, refrigeration and cultivation of warfare specimens are important tasks in determining the types of biological warfare agents, and also an important guarantee for winning the anti-drug war. Therefore, in the future anti-drug warfare and daily sanitation and epidemic prevention work, higher requirements are put forward for the functions of sampling, refrigeration and incubator. Based on the analysis of the main defects of the sampling, refrigeration and incubator of the existing equipment, we have conceived and developed the “multi-functional sampling refrigerating incubator” based on the different anti-bio-combat environments and characteristics combined with the existing high-tech technology. It is used for sampling, refrigerating and cultivating biological warfare agents such as viruses, bacteria, rickettsia and fungi in anti-virus warfare. Production, inspection, cultivation, experimentation, disinfection, storage, scientific research, etc. in the field of large-scale on-site activities such as medical support, medical, health and epidemic prevention, pharmaceutical, and environmental protection.

1 Existing equipment has major problems and improved ideas

1.1 Main problems:
At present, the portable sampling, refrigerating, incubator, sampling, and refrigerating are basically in the mode of ice block and incubator, and the incubator is heated by electric heating wire. The functions of the three boxes are respectively the collection and storage box of the on-site warfare agent specimens, and then the warfare specimens are stored in the refrigerator and sent, and the warfare specimens are stored in the incubator for cultivation. The main problem is that there are more carrying cases, longer preparation time, and more operations. The cooling of the ice cube depends on the rear support and the use time is short. Incubation time of the incubator, low energy conversion efficiency, and no self-supplied power supply capability. Warfare specimens are susceptible to contamination and warfare specimens contaminating the environment during operation. The three-box technology is relatively backward, with large volumetric weight, strong dependence on the mains, and inconvenient carrying, and is not suitable for use in field conditions.

1.2 Improved ideas:
We design, integrate, sample, refrigerate, culture, and self-supplied solar power through modern technology, and automatically control the sampling, refrigerating, and cultivating the required temperature through a computer. It has the functions of sampling, refrigerating and incubator, and has the function of joint use. In this way, in the execution of the task, the number of carrying the box can be reduced, the weight can be reduced, and the utility model can work without depending on the mains, and is particularly suitable for use in the field.

2 The main problem solved

The purpose of the "multi-function sampling refrigerating incubator" is to provide a collection, refrigerating and cultivating function, which is intelligent, light, consumes less energy, and has high energy conversion efficiency, which is convenient for field work. The key is to solve the problems of integrated design of heating and refrigerating devices, mainly to design and install composite high-efficiency heating and cooling devices and temperature control devices in the box. When the culture function is started, the heating device starts to work. We change the traditional heating wire heating mode. The heating device is an infrared heating film attached to the inner partition of the inner liner, and a gold-plated reflective film is sprayed around. Infrared heating film, temperature control device and lithium battery are electrically connected. After the power is turned on, the infrared heating film directly heats the culture body. Since the thermal inertia of the outer heating film is extremely small, 0.8 s can reach 5% of the rated power after power-on, and about 1 s can reach 80% of the rated power, about 2 s. It can be operated at full power and the temperature rises quickly and accurately. Spraying a rare metal such as titanium or gold on a certain part of the inner wall as a directional reflection layer can greatly improve the heating efficiency and lower the temperature of the reflector. The reflective film reflects back the energy of the scattering portion, and the conversion efficiency of the electrical energy into thermal energy is significantly improved.

When the power sampling and refrigerating energy are started, the semiconductor refrigeration chip is compositely mounted on the inner wall of the tank, and the refrigeration device starts to work. The semiconductor refrigeration chip acts as a refrigeration system, and has no noise, no pollution, and is quick to start. The upper layer of white frost begins to cool down, and the temperature inside the box can be monitored in real time, which is convenient and rapid. Therefore, it has opened up a new branch of refrigeration technology, solving the refrigeration problem of the special occasion of the multi-purpose sampling refrigeration incubator, in line with the needs of people in special occasions.

Solar cells provide power for charging lithium batteries. The lithium battery is small in size and light in weight. Therefore, when the overall volume and weight of the incubator are not significantly increased, the utility model can be used normally without an external power source, and is suitable for use in field conditions without a commercial power. At the same time, since the heating is directly heated by the infrared heating film, the reflecting film reflects back part of the energy and continues to be utilized. Therefore, the internal resistance wall body and the casing are less heated, so that the temperature difference between the temperature and the ambient temperature is small. Therefore, the amount of heat lost through the casing is also small, so that the thickness of the casing can be reduced, thereby achieving the purpose of reducing the weight and reducing the volume of the outer casing of the incubator. The above technology has been adopted, and the purpose of sampling, refrigerating, and cultivating multi-functional integration has been realized without increasing the weight and volume.

3 Technical indicators

Main technical data:

Power supply: AC 220V frequency: 50 Hz, DC l2V, too

Yang can supply its own power supply;

Power: 30 w;

Temperature adjustment range: 0~C~50°C;

Temperature difference inside the box: ≤ ±1.5~C;

Dimensions: N / A;

Volume: can put about 10 petri dishes with a diameter of 10;

Temperature drift (± ° C): 0.5;

Time: adjustable

Weight: 3 kg.

4 Working principle

4.1 Heating principle:
In the existing electric heating method, infrared heat energy is called intelligent heat energy, because it has obvious advantages compared with the conventional convection or contact type heating method. We use high quality infrared radiators and specially designed modules and control units to provide the ideal heating solution. Infrared radiation heating method can reduce the dielectric loss during conduction convection in a large proportion, form a multi-superimposed directional energy field in space, has strong transient, and the thermal photon beam current released on the surface is various Through the infrared control system, the material selection can achieve the best matching and absorption to the best heating effect, achieve the purpose of multi-level synchronous heating, and reflect the good thermal insulation quality. The hot beam flow emitted by the heat beam is evenly distributed in the radiation plane, which overcomes the problem of uneven radiation distribution of various heating elements in China.

A plurality of infrared heating molds are mounted on the inner wall of the tank, and a gold-plated reflective film is mounted thereon to increase the effective radiation. Infrared radiation technology has high radiation density and extremely fast response time with a reaction time of just a few seconds. The fast reaction time provides excellent controllability to the field multi-function sampling refrigerating incubator. Far red ~l, Jn heat has many advantages such as fast heating speed, good thermal uniformity and high thermal efficiency compared with traditional heating methods. . It can be used to replace electric heating, generally saving about 30%, and even 60% to 70% in individual occasions. It is an ideal energy efficient material. Under the above technical solution, the inner partition of the inner tank is set as a horizontal glass plate, and the infrared heat-generating film is attached to the glass plate. In this way, the glass culture vessel is directly placed on the transverse glass plate of the film, and after the power is applied, the infrared heat-generating film directly heats the glass culture vessel, thereby further improving the conversion efficiency of electrical energy into heat energy.

At the same time, since the heating is directly heated by the infrared heating film, the reflecting film reflects back part of the energy and continues to be utilized. Therefore, the internal resistance wall body and the casing are less heated, so that the temperature difference between the temperature and the ambient temperature is small. Therefore, the amount of heat lost through the casing is also small, so that the thickness of the casing can be reduced, thereby achieving the purpose of reducing the weight and reducing the volume of the outer casing of the incubator.

Electric heating design:

(1) First, it is necessary to determine the heating time (H) and the temperature difference (degrees), and how long it takes to rise from how many degrees, this parameter is very important. If the time requirement is very short, the required heating power may be very large, wasting energy; if the time is long, the equipment is ready

It is long and needs a balance point.

(2) The volume of air (m3) in the main equipment.

(3) Specific gravity of air: 1.16 (Kg/m3); specific heat: 0.24 kcal/kgoC.

(4) There is also heating efficiency, generally 0.5 to 0.6.

Calculated according to the following formula:

Heating power (KW) = (volume x specific gravity x specific heat x temperature difference) / (860 x heating time x efficiency).

4.2 Refrigeration principle:
The thermocouple composed of the N and P components of the thermoelectric cooler functions as a general refrigeration compressor. The cold end of the thermoelectric cooler and the exchanger for heat dissipation are equivalent to the evaporator of the ordinary refrigeration compressor, and the hot end Its heat exchanger is equivalent to a cold suspect. When energized, the free electrons and holes move away from the cold end of the thermocouple to the hot end under the action of the external electric field, which is equivalent to the compression process of the refrigerant in the refrigeration compression. At the cold end of the thermopile, heat is absorbed through the heat exchanger, and an electron-hole pair is generated, which is equivalent to the heat absorption and evaporation of the refrigerant in the evaporator. At the hot end of the thermopile, electron-hole pair recombination occurs, and heat is dissipated through the heat exchanger, which is equivalent to the heat release and condensation of the refrigerant in the cold suspect, which is 90% more energy efficient than the compressor refrigeration.

Refrigeration design:

(1) Determine the temperature to be reached by the object being cooled.

(2) Determine the maximum current value of the cooling element.

(3) Determine the heat load, the heat generated by the object to be cooled and from the outside

The heat that penetrates.

(4) Select which heat dissipation method to use (natural convection heat dissipation,

Forced convection heat or liquid cooling, etc.) and heat at the hot end and surrounding medium

Exchange factor.

(5) Determine what kind of heat exchange between the cold end and the object to be cooled

Formula (close contact or liquid circulation, etc.) and heat exchange coefficient.

(6) Determine the cooling rate and the time to reach the temperature.

QT=QB+QA+QP+QM(W)

Where: QB-case leakage heat (w);

Q opens the door to leak heat (W);

Q Bu storage heat (w);

5 discussion

By analyzing the main defects of the existing equipment, we combined the existing high-tech technology with the existing high-tech technology, and conceived the original sampling, refrigerating, refrigerating and cultivating three independent functional boxes according to the requirements of use. Optimized portfolio design.

Compared with the existing equipment, the “multi-function sampling refrigerated incubator” has a multi-purpose box, convenient use, small size, light weight, multiple functions, precise temperature control, small dependence on the outside world, long use time, energy saving, safety, etc. Advantage. The prototype of the product was applied in the field from the autumn and winter of 2006 to the spring of 2007. The performance of the instrument was generally stable, the operation was simple, and the effect was reliable and practical. It can be widely used in production, inspection, cultivation, experimentation, disinfection, storage, scientific research, etc. in military medical, health and epidemic prevention, pharmaceutical, environmental protection and other industries.

( MedicalEquipment, Zhang Yuhui, Jia Lin, etc. )