The NASSAU Fruit Pitting Machine 2021-1

Compared to the original design the maximum fruit diameter has been increased from 25 to 30mm, this to make the machine suitable for cherries and mirabelles a.o. fruit with a central stone and a current product size up to diam. 30 mm. The fruit is supplied from a container mounted on a vibration unit, creating a kind of fluid bed which prevent bridging of the fruit objects. A dosing disk transports the product to a tube including an escapment to create a synchronic supply to the step-controlled carrousel. The fruit moves in the cup to the pitting position. The pneumatic cylinder with the piston causes a swift stoning. Resulting treated fruit and the stone are collected in separated baskets.

Two microcontrollers Arduino UNO are programmed to deliver the various functions. Rotation of the carrousel and the dosing disk are arranged with the two stepmotors connected to the drivers and acting in a regular synchronic sequence according the code (A). In the same code also the action of the solenoids on the pneumatic valve and the escapment is scheduled. A compressor provides the air at 2-4 bar for the pneumatic system. Cooling of the drivers is arranged with the exhaust air from this system.

A separate code (B) measure the number of stoned products and the time between the pitting actions (interval time). Values are displayed on the lcd situated on the measuring unit. This unit is also equipped with a PWM potentiometer which controls according code B the action of the vibration unit.

With an interval time of 3,5 s a nominal production is calculated to be 900 stoned fruits per hour.

The installation is made of stainless steel, except some parts with a galvanic protection.