Vietnamese master creates automatic lemon peeler

Master Tran Le Trung Chanh, Polytechnic School, Can Tho University, has created a prototype automatic lemon peeler that can peel 240 lemons in one hour.

In 2016, Master Chanh and a delegation from Can Tho University studied the need for technological application and innovation in Hau Giang. He noticed that some households peeled lemons manually or with semi-automatic machines with low productivity.

At that time, there were many automatic lemon peeling machines on the market , but most of them required placing each lemon in the peeling area or the material feeding area, which was a waste of labor and time for workers, and the level of automation was not high. From this reality, Master Chanh set the goal of creating a fully automatic lemon peeling machine. The manager only needed to put many lemons in the feeding area at once, then the system automatically located each lemon and brought it to the peeling knife.

Testing the operation of the automatic lemon peeler. (Video: NVCC).

After more than 1 year of research, the author successfully manufactured an automatic lemon peeler with a mechanism consisting of 5 main parts: rough feed, orientation, pin, rotation and peeling knife. When starting the machine, the lemon is put into the material storage area and falls into the hopper with a transport spiral shaft. Each lemon is brought to the position of the centrifugal roller mechanism. Next, the pin head will hold and rotate 90 degrees to keep the lemon upright. At this time, the opposite pin head will lower down to hold the other end of the lemon and rotate. At that time, the peeling knife moves to the position of the rotating lemon to perform the peeling operation from bottom to top in a circular arc to the entire surface of the lemon. After completion, the rotating needles stop rotating and the peeling knife stops, ending the peeling process, repeating the cycle with the next fruit.

The test results showed that the machine achieved an average peeling efficiency of 85% of the lemon peel surface, with a productivity of 240 fruits per hour, equivalent to 24 kg of peel. According to Master Chanh, the cleanliness of the peel depends on the peeling depth and the fiber cutting (the width of the peel after cutting) from the fruit. The author evaluated the average peeling depth of 1.86 mm and the average fiber cutting of 3.1 mm as the most optimal.

The product he researched is currently in its early version, so its productivity is still low and the peel cleanliness is not absolutely perfect. Currently, the machine can peel medium-sized lemons and above.

The author said that in the near future, he will improve the mechanisms to accommodate all sizes of lemons, helping to maximize the peeling capacity of existing lemons. The machine will be designed with a part that holds the peel and fruit after peeling. He also plans to develop a pineapple peeler based on the mechanism of a lemon peeler.

Author's design diagram of a lemon peeler. (Photo: NVCC).

Mr. Hung Tran, a machine design and manufacturing expert, assessed that although the product is not new, it has applications in serving the mechanization of agricultural product processing, freeing up labor. However, he said that the machine is in the form of a model, with low productivity. In addition, the fruit positioning mechanisms and the needle tip that fixes the lemon operate with high errors. He said that the needle tip that fixes the lemon must be sturdy so that when rotating at high speed, it does not affect the peeling process and the fruit does not fly out. "The author needs to optimize the mechanical processing of the machine by designing parts that are sturdy, durable and operate accurately. This helps the machine work continuously without errors, achieving high peel cleanliness ," he said.