“无压风门”是河北煤研所承担的部一般科研项目，是针对传统风门压力大难以启动的技术难题而提出的，在项目鉴定前考虑有关关键技术有独特之处，而且结构也比较新颖，为了加强对“风门”的保护，决定对一些关键技术进行专利保护。在专利申请前查新工作中发现，该技术已由现场 “Unpressurized damper” is a general scientific research project undertaken by Hebei Coal Research Institute. It aims at the difficult technical problems of traditional damper pressure. It is unique to consider the key technologies before project identification, and the structure is relatively new , In order to strengthen the “damper” protection, decided to patent some key technologies. In the new work before the patent application found that the technology has been on the scene