Title of Invention  DESIGN AND DEVELOPMENT OF A COCONUT DESHELLING MACHINE 

Abstract  Traditionally after partial drying of split coconut, the kernel and copra is separated using a traditional wooden mallet by taking the individual cups in hand. To over come this problem, a power operated coconut deshelling machine was designed and developed. The capacity of the machine was 400 half cups per batch. The optimum average moisture content for maximum deshelling efficiency (92.16 %) was 35 % d.b. The optimum speed of the deshelling machine was 10 RPM and the time taken for deshelling was 4 minutes per batch. Cost of the machine was Rs. 27,100 and the cost of deshelling 1000 nuts was Rs.53.00. 
Full Text  3. PREAMBLE TO THE DESCRIPTION The following specification particularly describes the invention and the manner in which it is to be performed. Traditionally after partial drying of split coconut, the kernel and copra is separated using a traditional wooden mallet by taking the individual cups in hand. To over come this problem, a power operated coconut deshelling machine was designed and developed. The design drawing of the deshelling machine is given in Fig.l. The dimensions of the cylindrical deshelling chamber were calculated as 90 cm diameter and 115 cm length to hold 200 split coconuts at an average moisture content of 35 % d.b. based on bulk density and porosity values. Loading and unloading of partially dried copra was done manually. Three flights having 29 x 22 cm cross section running throughout the length of the drying chamber were fixed inside the deshelling chamber at a distance separated by 120 . The lip angle of the flight was fixed o at 70 based on preliminary tests conducted, so that the nuts can fall freely from the flight uniformly in the deshelling chamber. The horse power required to rotate the cylindrical deshelling chamber at 10 RPM was calculated as 3.0. To achieve the required low speed a reduction gear box with a set of pulleys were fixed. A 3.0 phase 3 hp electric motor was coupled to rotate the deshelling chamber at the desired RPM. 4. DESCRIPTION Fabrication of major components Main axle The main axle was fabricated using 60 mm (φ OD) mild steel shaft of 1.75 m length which was provided with 2 bearings at the ends and one pulley to rotate the deshelling chamber freely. Main support frame The main support frame was fabricated using 75 x75 x8 mm mild steel angle to withstand the load of the deshelling chamber and copra. The height of the deshelling chamber was fixed at 110 cm for easy loading and unloading of partially dried copra. Method of operation Partially dried copra was loaded in to the deshelling chamber manually. The capacity of the deshelling chamber was 400 partially dried half cups. When the average moisture content of the copra reached 35 % d.b. the door of the deshelling chamber were opened and copra was loaded. The deshelling chamber was allowed to rotate at a speed of 10 RPM for different periods and the deshelling efficiency was calculated. The cost of deshelling machine was worked out to be Rs. 27,100.00. The optimum number of rotations was 40. The deshelling time based on the speed of the reduction gear output was four minutes. The design details are given below. The dimensions of the deshelling machine were determined based on the bulk density of split coconuts for 200 nuts capacity. Bulk density of coconut at a moisture content of 35 % d.b = 380.593 Approximate weight of 200 split nuts, m = 84.26 Kg Let the length of the deshelling machine be = 115 cm (Length has been assumed instead of diameter as diameter is taken from experiments conducted to include the height of fall for separation) The radius of the de  shelling chamber can be determined by using the equation .. hp = 2.90 Hence, a 3 hose power motor (standard size) that was available in the market was coupled to the reduction gear box unit so as to rotate the drum at the optimized speed of l0 RPM The deshelling machine was tested for its performance evaluation with partially dried copra having moisture content in the range of 66.4 to 25.7 % d.b. and it was found that the optimum average moisture content for deshelling was 35 % d.b. At 35 % (d.b.) moisture content the deshelling efficiency was 82.5 %. Five replicate tests were conducted for each moisture content and the average values were used for calculations. The increase in deshelling efficiency with respect to decrease in moisture content is given in Fig. 2. The effect of number of rotations on the deshelling efficiency were explored by keeping the moisture content constant at 35 % d.b. Nuts (400 half cups) were loaded manually and the machine was operated. It was observed that after 40 rotations practically there was no further increase in the efficiency of deshelling (Fig. 3). On careful examination it was also observed that unless the coconuts are of the same maturity the efficiency will not increase due to uneven moisture content in the partially dried copra. At 30 rotations the efficiency of the machine was 85.64 %, at 40 rotations the efficiency was and 92.16 % and this further increased to 93.5 % by rotating 50 and 60 times. Hence the optimum number of rotations was fixed as 40. Thus the deshelling time based on the speed of the reduction gear output was four minutes. The increase in deshelling efficiency with respect to number of rotations is given 

672che2006correspondenceothers.pdf
672che2006correspondencepo.pdf
672che2006descriptioncomplete.pdf
Patent Number  233742  

Indian Patent Application Number  672/CHE/2006  
PG Journal Number  20/2009  
Publication Date  15May2009  
Grant Date  02Apr2009  
Date of Filing  12Apr2006  
Name of Patentee  INDIAN COUNCIL OF AGRICULTURAL RESEARCH  
Applicant Address  Director, Central Plantation Crops Research Institute, Kasaragod, Kerala 671 124,  
Inventors:


PCT International Classification Number  A23N 5/00  
PCT International Application Number  N/A  
PCT International Filing date  
PCT Conventions:
