Research and development of multi-chamber and multi-temperature numerical control thermostatic Water Bath

Constant temperature Water Bath (Water Bath) is widely used in production units, medical units, quality supervision departments, scientific research departments and colleges and universities to carry out distillation, drying, concentration, constant temperature heating of various solutions, impregnation of drugs and biological agents and other temperature tests, etc. , It is the required equipment for teaching and scientific research in biology, genetics, virus, aquatic products, environmental protection, medicine, health, biochemical laboratories and analysis laboratories.

1 The functional requirements that the Water Bath should meet

In order to meet the different needs of production, scientific research and teaching, the constant temperature Water Bath or Oil Bath should have the following basic functions.

1.1 Precise and stable temperature control

According to different needs, the constant temperature Water Bath equipment should have two basic functions of heating and constant temperature. Under the existing technical conditions, using the traditional mechanical contact control temperature control system, single-chip microcomputer system and fuzzy control system [1 ~ 3], all kinds of Water Baths can basically make the temperature control accuracy of the equipment reach ±0. 1 ℃ ~ ±1 ℃, the heating temperature range is room temperature +5 ℃ ~ +99 ℃, which can basically meet various application requirements. The new type of equipment , on the basis of adopting relevant precision components, utilizes numerical control technology to realize the design of multi-point centralized temperature control, and can fully meet this basic requirement.

1.2 The material is anti-corrosion and durable

Because it is a Water Bath heating equipment, it is generally clean. In terms of heating and temperature control systems, the service life should be more than 10 years, and the safe service life of some equipment has even reached more than 40 years.

1.3 Heating space is abundant

Constant temperature Water Bath equipment is used in many fields, so the number and volume of utensils that need to be heated are relatively large. In order to meet a variety of needs, different types of Water Bath equipment have different heating inner tank volume ranges. At present, most Water Baths use a common Water Bath liner and multiple heating hole panels to basically meet the requirements of simultaneous heating of multiple vessels.

1.4 Safe and convenient to use

In the laboratory safety management, the human factor plays a decisive role [4], but the safety protection function of the experimental equipment itself is equally important, needless to say. Like all electrical experimental equipment, the design and manufacture of Water Bath constant temperature equipment should pay special attention to the safety performance of operation and use, and eliminate various . The use and operation of the equipment should be simplified as much as possible for different users; the overall weight and dimensions be made more humanized.

1.5 Focus on low carbon and energy saving

At present, the whole society is working hard to realize a low-carbon economy. The so-called low-carbon economy refers to the reduction of greenhouse gas emissions as much as possible through technological innovation and institutional innovation without affecting economic and social development , so as to slow down global climate change and achieve economic and social clean development and sustainable development. Sustainable development [5]. There is a lot of room for energy saving in the design and manufacture of Water Bath constant temperature equipment. Therefore, this factor should be fully .

2 The characteristics and deficiencies of the existing Water Bath constant temperature equipment

At present, the constant temperature Water Bath and Oil Bath equipment used in the above aspects in CHINA, whether it is a constant temperature Water Bath or a precision constant temperature Water Bath, are mostly single temperature control single tank porous Water Bath equipment of different specifications and models, and the heating temperature range is room temperature +5 ℃ ~ +99 ℃, temperature control accuracy is ±0.1 ℃ ~ ±1 ℃. Although this type of equipment basically meets the needs of relevant scientific research and teaching, it has the following significant shortcomings.

2.1 Single temperature heating

Although the existing various Water Bath constant temperature equipment has holes for simultaneous heating and constant temperature, each hole belongs to the same Water Tank and can only have one temperature, which cannot meet the requirements of multiple temperatures for simultaneous heating and constant temperature; although there are three holes and three temperature constant temperature Water Baths The pot is available on the market (Figure 1), but it uses a single-temperature and single- control temperature control system. Due to its limitations, the number of heating chambers must be limited, otherwise overall structure of the equipment cannot be reasonably compact.

2.2 Slow temperature regulation

通用的恒温水浴设备一般应具有多种使用范围。而使用现有的大多数水浴设备，当只需要加热恒温单个容器中的少量溶液或物质时，也得调控整个

水槽中的10 升 ～20 升水温，这就必然是既用水量大、浪费能源，又耗时较长，无法达到既节能又快速升温的操作要求。

2。3 附属配件不足

在科研及实验教学工作中，经常需要加热恒温具塞比色管或试管中的少量待测溶液或反应液，而现有的各类水浴恒温设备中，水槽或水筒内都没有配备任何用于放置试管等管状容器的附属配件，给这类容器的加热恒温带来很大不便。 笔者在以往的工作实践中，不得不自制一些适用于水槽容积的金属试管架，用于放置比色管等。 虽然这种相应的试管架仅用于加热小型管状容器，但在多用途恒温水浴设备产品的设计中，它也应是所需附件。

2。4 循环噪音较大

较高级一些的精密恒温水浴槽中，一般带有内置水循环泵。 它一方面用于温水的外循环，另一方面为了使整个槽内水温均匀而进行内循环。 在实际使用中，大多数产品的循环泵循环效果较好，但噪音较大，影响操作环境;但若不开泵，由于水槽较大，会增大槽内水温温差，因此，这一设计上的矛盾难以消除。

3 新型产品的性能及特点

本研究是在综合现有相关设备特点的基础上，设计开发出了系列多加热室多温度的新型恒温水浴设备，在温控技术、水浴室大小及结构设计等方面做出较大突破，使其在节约资源、提高加热恒温效率、降低设备成本方面，走在国内同类设备的最前沿。

3。1 采用了温度数控技术

要实现同一水浴恒温设备中的多室多温，温控技术是其中的关键环节。 实践证明，只有采用温度数控技术，才能达到集中控制的多点控温要求。 而传统的单温控系统模式，是难以满足这一要求的。

目前，成熟的单片机系列产品不断推出［6］ ，单片机温控技术也已应用于多个领域 ［7，8］ 。 将该技术应用于恒温水浴设备后，现有的产品仍然限于单温控设计，只是提高了控温质量。 本文在此技术上，采用了独特的软硬件设计，实现了多个小加热室的单独控温操作及温度数显，各室之间可以同温也可以不同温，这样既满足了传统水浴锅的加热恒温要求，也满足了多数情况下需要多个温度同时恒温的快速操作要求。

3。2 新颖的整体结构设计

本研究开发的水浴恒温设备，一改以往单一水槽的结构特点，采用了多个小型水浴室的结构设计。 各单体水浴室水容积不超过1 升，可满足300 毫升烧杯、锥形瓶、圆底烧瓶等玻璃或金属容器加热恒温需求。 According to不同使用要求，水浴室数量可以是4 个 ～ 9 个。 各水浴室的排布可以是条形、方形或环形。该水浴恒温设备采用不锈钢箱体及圆柱形水浴室，各室之间填充保温绝热材料。 为了使设备整体结构紧

凑合理，保温材料选择一体成型的泡沫塑料，将多个水浴室嵌入固定在绝热材料的整体框架中。为了特殊需要，该设备还选择性地配备有外置式水循环泵，以供对外输送循环温水。 同样，为了加热比色

管或试管需要，该设备附带有与水浴室内径相符的不锈钢网状试管架。

3。3 新型产品的性能特点

(1)本产品实现了各水浴室温度集中控制，温度分别数显。 单室加热温度范围为室温 +5 ℃ ～ +99 ℃，温控精度为 ±0。1 ℃。

(2) The maximum heating power of a single Water Bath is 300 W. When it is necessary to heat a small-volume liquid at a constant temperature, it highlights its advantages of saving water, electricity  time.

(3) Due to the small size of a single Water Bathroom, the heating speed is fast, and the temperature difference of the whole water temperature is small, and the indoor water circulation system noise and vibration caused by the built-in water circulation pump, and reduces energy consumption at the same time. The structural design is simplified.

(4) Each Water Bathroom has an independent drain valve, and the multi-room common drain outlet.

4 Conclusion

The series of products launched in this research have improved the working efficiency and control precision of the constant temperature Water Bath under the condition of the same material as similar products. The manufacturing cost and market price are comparable to similar products, but the cost performance has obvious advantages and good economic benefits. and promotional value. references:

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