论文部分内容阅读
本文第一部分叙述了气动冲击机构的基本理论,对热力学理论的应用原则提出了新的见解。在工程热力学和气动技术领域,过去通常强调,把一定量自由空气升压至确定值,绝热过程耗功最大,等温过程耗功最小。因而认为,应使压气过程尽量接近等温过程而远离绝热过程。本文指出,由于气动冲击机具是将压气有效能量转化为活塞动能的过程,而通过升压使一定量自由空气获得确定的可供利用的有效能量,等温过程耗能最大,而绝热过程耗能最小。因而认为,对于包括压气制备和压气利用的整个风机系统来说,应使其尽量接近绝热过程而远离等温过程。第二部分对气动冲击机具的传统结构进行分析,论证了传统结构很低的有效热效率是它的结构缺陷所造成。并推导出了传统结构有效热效率的极限值。第三部分提出并论述了LF型气动冲击结构。LF型结构是一种与传统结构相反的气动冲击结构。它将使现有各种气动冲击机具的有效热效率成倍提高,并使噪声显著降低。在导出计算公式并作了实例计算后,阐明LF型结构是气动冲击机具的一种理想结构。
The first part of this paper describes the basic theory of pneumatic impact mechanism, put forward new ideas on the application of thermodynamic theory. In the field of engineering thermodynamics and pneumatics, it has generally been emphasized in the past that when a certain amount of free air is boosted to a certain value, the adiabatic process consumes the most energy and the isothermal process consumes the least energy. Therefore, we believe that the process should be as close to the isothermal process and far away from the adiabatic process. This paper points out that because the pneumatic impact equipment is the process of converting the effective gas pressure into the kinetic energy of the piston and the certain amount of free air can be obtained by boosting the effective available energy, the isothermal process consumes the most energy while the adiabatic process consumes the least energy . Therefore, it is considered that for the entire fan system, including gas preparation and gas utilization, it should be kept as close to the adiabatic process as possible away from the isothermal process. The second part analyzes the traditional structure of the pneumatic impact equipment, demonstrating that the effective thermal efficiency with low traditional structure is caused by its structural defects. And deduced the limit value of the effective thermal efficiency of the traditional structure. The third part presents and discusses the LF-type pneumatic impact structure. The LF-type structure is a pneumatic impact structure that is the opposite of the conventional structure. It will double the effective thermal efficiency of existing pneumatic impact machines and significantly reduce noise. After deriving the calculation formulas and calculating the examples, it is clarified that the LF structure is an ideal structure of the pneumatic impact tool.