Black Pepper thresher

Consolation Awards

P. K. Ravi
City: Murikkassery
State: Kerala

P. K. Ravi (32), a workshop mechanic, hails from Murikkassery, Idukki in Kerala. He runs his own workshop, “Our Engineering Industry”. He is married and has two children. Right from his childhood, he has shown interest in repairing machines. He was not interested in studies and discontinued them after completing his intermediate course. He started his own workshop four years ago after having gained experience in welding workshops.

Genesis Sometime ago, Ravi was faced with a financial crisis and the work in his workshop came to standstill. He was forced to think of some other means of supplementing his income. Belonging to Idukki district in Kerala which has huge pepper plantations, he was aware of the problems faced by farmers in threshing pepper especially as manual threshing is a very tiresome and tedious job. This made him think of making a pepper thresher. He consulted a number of people in this regard, but did not get any encouraging response. But refusing to be discouraged, he started working on it and developed a pepper thresher on his own. He tried threshing some pepper which he had at home and found that it was successful. He claims that his machine, which he has named ‘Aurora’, is superior to all the machines available in the market. For the last three seasons, several pepper growers in different areas have been successfully using his machine. Ravi has filed a patent application for this innovation. This innovation has been widely covered in the various newspapers of the state.


As compared to the conventional thresher, Ravi’s innovation has a number of advantages. This innovative machine can be operated automatically and manually whereas the conventional thresher can only be operated manually. His small machine can thresh 300 kg pepper in an hour, as against the comparative conventional device which can just thresh 70 kg in an hour. Ninety per cent f the berries can be separated from the spikes in one run and no damage occurs to the skin of the pepper whereas in the conventional device 20 percent of the skin is destroyed. The manually operated model costs Rs. 5000 and the mechanically operated machine costs Rs. 12,000 whereas the current devices available in the market cost Rs.15,000. In the innovative thresher, pepper can be collected at one place without the need of manual labour but in the conventional device it needs to be collected manually. The operation of this innovation is simpler and easier. P.K.Ravi’s innovation has the further advantage that by changing the leaf blade, it can be used for threshing white pepper and paddy as well whereas the conventional device cannot be used for threshing paddy or other grains.

Testing and evaluation

The Spices Board (Ministry of Commerce and Industry, Govt. of India) has recognized his innovation and included it in the board’s subsidy scheme. The report given by the board attests to the cost-effectiveness of the device. It states that manually one labourer can separate 150 kg of berries from spikes in a day, whereas, using this equipment 300 kg of berries can be separated in an hour. Thus the wages of two labourers per hour can be saved as for operating this machine only one person is enough for the whole day. The electricity consumption per hour is less than one unit (1 kilo watt).

The Faculty of Agricultural Engineering and Technology, Kerala Agricultural University evaluated the pepper thresher developed by Ravi and have noted that the average threshing efficiency observed is 90percent with only 2 to 3 per cent damage. They also recommend this machine as cost effective and easy to operate and handle.

The thresher developed by the innovator consists of a feeding hopper made of iron sheet, a rotating wire-loop type threshing drum and a concave metal sheet with perforated bottom, all of which are mounted on the main frame. Power from an electric motor is transmitted through the V-belt and pulleys to the threshing drum. The machine also has the facility of manual operation.

The harvested pepper spikes are directly fed to the hopper, in the rotating drum. The threshed pepper passes down through the perforations and gets collected at the berry outlets. About 100 kg pepper can be threshed in a one HP machine in ten minutes (50 kg in a ½ HP machine) The machine is stopped to cleaned to remove unthreshed spikes, cords and other debris after operation. Intermediate cleaning can be also done by manual cranking of the threshing drum. After cleaning, the machine is ready for the next fresh lot of pepper spikes. It can be operated with or without a motor and it can be operated by a single person. A one HP or half HP motor can be used. The machine also has a separate system to grade the threshed pepper. Ravi has made two models of the machine. A big model which has a capacity of 100 kg and can thresh 600 kg of pepper per hour and a small model which has a capacity of 50 kg and can thresh 300 kg/ hr. The average threshing efficiency observed is 90percent with only 2 to 3 percent damage.