Due to the climatic characteristics of northern
Vietnam, seasonal boundaries are sometimes
unclear. When temperatures shift early from
cold to warm conditions, pineapple plants tend
to flower and set fruit prematurely, resulting
in substandard fruit quality. To address this
issue, pineapple growers apply a practice of
tying pineapple leaves and crowns to inhibit
early flowering, thereby maintaining vegetative
growth until the main season, when plants reach
the appropriate stage for flower induction. This
practice contributes to increased yield, improved
fruit quality, and enhanced production scheduling.
At present, the tying of pineapple leaves and
crowns is performed manually, which is laborintensive and results in low productivity. To
improve operational efficiency, the development
of a suitable tying device is necessary. This paper
presents the research results, calculations, and
design of a handheld pineapple leaf-tying device.
The device consists of two main components: a
crown gripping unit and a wire-tying unit using a stapling mechanism. The crown gripping
mechanism simultaneously performs two
functions—gripping the crown and pulling it
into the tying space. The wire-tying unit is driven
by a cam–slider mechanism, which enables the
generation of a large pressing force required for
staple fastening while maintaining low power
consumption.The shoot clamping mechanism
performs two functions simultaneously: clamping
the shoot and pulling it into the tying space. The
strapping mechanism is driven by a sliding cam
mechanism, aiming for low power consumption
while still generating high clamping force for
stapling. The stapling process's drive mechanism
was simulated to determine the rotation angle of
the stapling arm at approximately 45° and the
required driving torque of the arm Mmax = 1.085
Nm
. The power of the electric motor driving the
arm is N
dc = 5 W.