Pencil Dispenser and Counter

Designers:  Leahthan Domeshek, Kelly Fong, and Evan Harrell
Client Coordinator:  Judy Stroupe, Orange Enterprises
Supervising Professor:  Larry Bohs

The Pencil Dispenser and Counter helps workers at a vocational rehabilitation facility count a specific number of pencils. The device is first loaded with pencils and set to a specific goal count by a supervisor. Once the set-up is complete, the worker pulls a lever to dispense and count one pencil, which falls into a bottom hopper with a folding wall. Each time the worker pulls the lever, another pencil is dispensed and the count is incremented on a large digital display.  An audible signal sounds when the worker reaches the goal count. The device is fairly inexpensive, portable, easy to operate and suitable for use by individuals who lack fine motor control.

How this project helped
In the past, employees at Orange Enterprises (OE, Hillsborough, NC) had difficulty handling and counting pencils.  An assistant oversaw and helped with pencil sorting at all times.  The Pencil Dispenser and Counter will help make employees more independent and efficient in this task, while still allowing them to be an important part of the process.   Judy Stroupe, a supervisor at OE, commented, “The employees used to count 8-10 pencils in an hour and then need a break, now they can count that many in five minutes.”

The Pencil Dispenser and Counter (Figure 1) uses a rotating cylinder with a slot big enough to hold one pencil. When the user pulls a lever, the cylinder rotates and the pencil falls into a bottom hopper.  A torsion spring helps return the lever and cylinder to the loading position. A stopper, padded for protection and shock absorption, stops the lever in the correct position to allow another pencil to fall into the slot in the cylinder. The cylinder shaft is supported on flange bearings to make it durable and easy to rotate.  The pencil container is V-shaped and holds at least 150 pencils in a compact space while also allowing easy loading of the cylinder.

The count is actuated using a momentary toggle switch, which resides in a circumferential groove in the cylinder.   The switch is activated when a pencil rotates past the switch as the lever is pulled down.  The switch is connected to a BASIC Stamp II microprocessor, which tallies the count and controls the system. An up/down rocker switch sets the goal count from 0-100 in increments of five, and a buzzer beeps four times once the goal count is reached. An LCD with large character display and a continuous backlight shows the number of pencils dispensed.  Four C batteries power the device for over 100 hours, and are easily replaced.

The pencils fall out of the cylinder into a bottom hopper, which has a slanted floor so the pencils roll down to the front of the device. The flap of the hopper is mounted to the main frame of the device using a hinge, and the flap can be folded up for storage. Quarter-circle walls attached to the sides of the bottom flap prevent pencils from spilling out during retrieval. Two integral clamps and rubber padding stabilize the device to a work table.  Figure 2 shows the device being used by an employee of Orange Enterprises.

The device was evaluated to assess durability, ease of use, effectiveness, and safety.  Durability was assessed throughout the design stages of the device and was the main reason for using the clamps, rubber bottom, and bearings.  Jamming was minimized to below one percent in a 500-pencil trial. After testing the device with employees, we determined that they could operate the lever and unload the pencils from the bottom hopper.

Figure 2 shows a client using the device at OE. Cost of parts for the Pencil Dispenser and Counter was about $400.

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