Constant force spring is small but as a basic part in common use,there are large amount and lots of kinds,its applications are involved in all the field that is connected with the nation economy, and make a great contribution to them.

What’s more,in recent years，with the fast development of the nation economy in our country,the industry of precision spring also develops rapidly. The experts predict the condition of  development will keep on, the sales volume will be more than 6 billion RMB till 2015.

According to the analysis,nowadays,there are five main markets in stainless steel power spring field: electrical equipment,shelf pusher,toys,sports goods and pet goods.
 
The application of constant force spring in shelf is mainly used in the shelves in the super market and display shelf. Such as auto propelling cigarettes shelves, vending machine,auto propelling cosmetic display shelf and so on.

　　
The application of stainless steel power spring in goods shelf can be divided into two parts: auto propelling shelf spring and the variable force shelf spring.

Their work form are the same,that is when customer take the first goods out of the shelf ,then the spring will make the next one to follow up and take the place of the previous one.In case leaving a blank in the shelf and avoid to have a person to order the goods on shelf.

The difference between them is whether the force is constant or not.

The biggest difference between variable force shelf spring and auto propelling shelf spring is that, the first one can work in different force with different distance.

It can satisfy for the special force request of some proteiform goods ,like cigarette,when you put ten boxes of them in a shelf as a group,at the number of ten,the force reach the maximum,if keeping this force till few boxes are on the shelf,the cigarette box may be distorted for the large force.

However,with the variable force shelf spring,the less boxes on the shelf,the less force it will be,and it will reach the minimize force when only one box on the shelf,this make sure the force of spring working on the cigarette box can be in a fit range and protect it from being distorted.