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China is one of the most important cotton-producing areas in the world. It is well known that cotton stalk is a kind of renewable biomass energy resource and can be widely used. Therefore, it is very important to research the harvesting techniques and equipment of cotton stalk, and design the cutting blade of cotton stalk. The conception of cutting effective rate was put forward on the basis of analyzing the cutting pattern of the reciprocating cutter, and it was used to describe the cutting characteristics of reciprocating cutter, because the cutting pattern of the reciprocating cutter could describe the cutting quality and height of the stubble of cotton stalk. In order to explore the effect of the knife section structural parameters(the width, height, and leading end width of the knife section) as well as the operating parameters(the average cutting velocity was 0.9 m/s, and the ratio of cutting velocity to feeding velocity was 1.25) on cutting effective rate of cotton stalk reciprocating cutter, and optimize the structural parameters of the knife section, the simulation test was performed with the ADAMS software. The simulation testing scheme designed with the box-behnken design(BBD) method was a three-factor three-level testing scheme, and the testing factors were the width of the knife section, the height of the knife section cutting edge, and the width of the leading end. The response surface analysis method was used to analyze the simulation testing data and optimize the knife section structural parameters of the cotton stalk reciprocating cutter. In order to observe and analyze the cutting process and morphological structure of the stubble as well as optimize the profile of the knife section, the cutting test was performed with a cutting test bench of cotton stalk by the high-speed photography technology. The samples were the ripe cotton stalks with the diameter of 11.7-13.2 mm, and the moisture content of 31%-37%, which were collected from a cotton field located at Shanghe County, Shandong Province. The results obtained from the response surface test showed that the effects of the width of the knife section, the height of the knife section cutting edge, and the width of the leading end on the objective value(the cutting effective rate) were significantly different(P<0.01), and the effects of the interactions between the width of the knife section and the height of the knife section cutting edge, between the width of the knife section and the width of the leading end, and between the height of the knife section cutting edge and the width of the leading end on the objective value were also significantly different(P<0.01).By analyzing the sequence images of cutting process of cotton stalk from the cutting test by the high-speed photography technology for cotton stalk, it was known that the effects of the different profile of the leading ends on the cutting quality of cotton stalk and the height of the stubble of cotton stalk were significantly different. It was concluded that the optimal combination of the knife section structural parameters of cotton stalk reciprocating cutter was that the width of knife section was 90 mm, the height of knife section cutting edge was 52 mm, the width of leading end was 15 mm, and the profile of leading end was arc-shaped. On the basis of the results of the verifying tests, it was found that the cutting effect of cotton stalk for cotton stalk reciprocating cutter with the new knife section was good, the height of cotton stalk cutting stubbles of the optimized knife section was 5.9 mm shorter than the standard knife section′s, the average value of cutting power per unit area of cotton stalk for the optimized knife section was 6.1% less than the standard knife section′s, and the smoothness of cutting stubble section of cotton stalk for the optimized knife section was 12% more than the standard knife section′s. The results of this research can provide technical support not only for developing a new cotton stalk cutter, but also for designing the equipment for harvesting hard stalk with a large planting area. [ABSTRACT FROM AUTHOR]

Cutting diagram is an important means of performance analysis of reciprocating cutter. The evaluation of working performance of reciprocating cutter principally depends on the size of 3 featured areas (repeated cutting area, area failing to cut and once cutting area), which can be observed from the cutting diagram. Drawing cutting diagram by the traditional manual tracing method has the disadvantages of low efficiency and imprecise result. Meanwhile the system of cutting diagram drawing and analyzing which is based on the MATLAB and other homemade programs cannot carry on the continuous analysis of parameter. Aiming at the inconvenience of the traditional methods, a cutting diagram analytic system was developed based on visualization platform. This paper took the standard ordinary I type reciprocating cutter as main research object, performed the kinematic analysis to cutting blade and obtained the moving-track curve of featured points. Method to calculate the 3 featured areas was deduced based on the kinematic analysis of the cutting blade. Moreover, 3 special situations which may happen during the calculation process were analyzed, and the respective solution for each situation was proposed. The software was developed based on VISUAL STUDIO 2008. The main interface of this system mainly consists of cutter parameter configuration zone, working property feature analyzing zone and cutting diagram drawing zone. After inputting the cutting parameter by user, system can draw corresponding cutting diagram and calculate the area of featured areas. The drawing of cutting diagram uses Picturebox control and GDI+ (graphics device interface plus) technology, and it can carry on the coordinate conversion to the actual dimension of cutting blade depending on the dimension of drawing zone. In order to adapt the calculation characteristics of computer, it uses the numerical analysis method in calculation process, including obtaining the coordinates of key points through the dichotomy solution to single-variable equation and calculating the area of featured areas by using the trapezoidal method to do definite integral calculation. The main content of working performance analysis is calculating the proportional relationship among the 3 featured areas under different working parameters, thus to find the best working parameters. Traditional method is to carry on comparative analysis by drawing many cutting diagrams, however, it has the shortages of hefty workload and imprecise result. This paper proposed a working performance analytical method depending on stepping calculation, which used the steeping method to automatically calculate and analyze the areas of 3 feature regions according to the cutter dimension parameters specified by users, and generated the corresponding curve graphs in set working parameter range. This provided the basis for users to analyze working properties of cutters and determine the best working parameters. The analysis of the standard ordinary I type reciprocating cutter showed that there was no area failing to cut when the rotator width was less than 44 mm, and no repeated cutting area when the rotator width was greater than 94 mm, moreover, when the rotator width equaled 61 mm, the area proportion of once cutting area reached the highest value which was 88%. Application result showed that the software had the advantages of convenient use, independence of the third platform and precise calculation result, which provided an efficient mean to optimize the operation of the reciprocating cutter. [ABSTRACT FROM AUTHOR]