The thermos also called vacuum flask, it was invented by England scientist duva .In the vacuum interlayer coated with argentum or reflection painting, get the thermal radiation back, Then plug the top of the bottle with a stopper.With the three way of heat conduction cut off, the refill can stay warm for a long time. He use this bottle store liquid hydrogen.It was widely used,and almost every home now has thermos.
Vacuum flask(vacuum cup), its walls are made of double glass, and between the double glass is a vacuum(vacuum lack of thermal conduction,that is to say the hot water is insulated from the outside by vacuum. Hot water is not easy to get cold, to achieve the purpose of heat preservation.Also its stopper normal use poor heat conductivity (such as wood ,hollow plastic..)
The thermos consists of inner glass refill, shell,additional components.
Thermos is made of two glass bottle. The top of two glass bottle connect together,two bottles of wall are pumped into a vacuum to reduce heat convection,the surface of glass bottle wall is coated with bright silver film reflecting infrared heat radiation.When high temperature inside the bottle,the contents thermal energy can not radiate outside. When low temperature inside the bottle ,the outside thermal energy can not radiate inside.The vacuum flask effectively controls the transmission,convection and radiation of three heat transfer pathways.
The weak point of vacuum flask is the bottle mouth. There have heat conduction in the point of two glass bottle connections,the mouth of the bottle is usually blocked by wooden plug or plastic plug.So the thermos has bigger capacity, smaller bottle mouth ,the higher effect of heat preservation.It is extremely important to maintain a long time vacuum in the two bottle interlayer. If the interlayer full of air or break the bleeding point, break the interlayer vacuum state, the vacuum flask loss of heat preservation effect.
Vacuum flask refill except made of glass , also have stainless steel refill and non-toxic,non-odorous plastic refill. Stainless steel refill is strong and durable ,not easy to damage,but thermal conductivity is bigger than glass refill, the heat preservation is poor.The plastic container made of single wall or double walls filled with foamed plastic for thermal insulation. It light and convenient, not easily broken,but thermal conductivity is bigger than glass refill.
The shell has a certain strength to protect the refill and increase the decorative effect.The shell is made of tin plate, brass, alloy aluminum, stainless steel and plastic, etc. China also has black iron, bamboo, bamboo, wood, enamel, etc.For the use of convenience and beauty, the shell can be used for a variety of modelling changes and to make a variety of decorations.Decorative methods include printing, spray painting, spray painting, electroplating, spraying, polishing, engraving, dyeing etc.
Different parts are provided according to the output water type. The ordinary thermos is suitable for holding the handle and pouring the water, and it needs to be equipped with plug, such as wooden plug ,rubber plug,ball control water in the cavity plastic plug,screw out of the sink plastic plug etc.The thermos with siphon outlet water should be equipped with siphon and valve gear in the bottle. The thermos with air pressure is called pressure thermos. It has two kinds of structure.
The commonly used is hold small air drum in the shell cover position, and press it with the hand or through the mechanism to make the liquid face air pressure through the pipe. The other is a small electromagnetic vibration pump that can be mounted on the shell to make the surface of the liquid be pressurized through the pipe. Big bottle mouth is used for store food ,as well as the installation of non-toxic plastic lining and configuration of the shape of a small package and other components.