Structural analysis and application research for controlled strand length cutting blade of rotary guillotine cutter

In the tobacco processing stage leading to the production of cigarettes, there are strict technical requirements for the structure and proportion of different lengths of cut tobacco following the cutting process. Moreover, the lightweight design of the high-speed rotary-cutting blades is of significant importance during this stage. To better address issues related to the rational design of the blade structure in rotary-cutting cutters and the effective control of size proportion of cut tobacco, this paper establishes a CLSC blade design method featuring concave-convex edges and inter-edge grooves, and provides specific structural schemes. By introducing the structure of the cutting components of the cutter and the cutting process, and by analyzing the differences in layout features between RSEC and CLSC blade structures, as well as their relevance to tobacco cutting and shaping, this paper establishes the installation constraints and mechanical load model for cutter blades under rated conditions. Finite element methods were used to model and analyze both types of cutter blade structures, yielding static and modal analysis data. Furthermore, production verification was conducted on an SD EVO cutter, and data on the rate of different lengths of cut tobacco were obtained. The results show that the mass of the CLSC concave-convex edge cutter blade was reduced by 4.33%, and the static stiffness efficiency was increased by 2.37 times. Although the first-six natural frequencies of the CSLC blade showed degradation in modal analysis, it still met the equipment vibration usage condition. The production verification results indicated that the use of CLSC concave-convex edge cutter blades reduced the long cut rate by 2.48%, increased the medium cut rate by 2.29%, broken cut rate increased by 0.08%, and increased the short cut rate by 0.12%, with an overall reduction in the whole cut rate by 0.19%, achieving the objectives of reducing the long cut rate, controlling the whole cut rate, and not increasing the broken cut rate. The CLSC blades were able to operate continuously, stably, and safely on the rotary-cutting cutter machine. The research presented in this paper can provide a reference for the analysis and design of cutter blade structures in tobacco cutter machines.