Can Opener

Revision as of 23:09, 4 February 2008

Function

This can opener is manufactured by Durabrand. The primary function of the can opener is to open cans by cutting the metal lid off. An electrical motor spins the geared wheel, which in turn spins the can. The blade remains stationary as it cuts the lid off.

User Requirements

• plug outlet
• magnet holds standard size canned product
• fits standard cans
• blade cuts through standard can lid
• small enough to fit on kitchen counter
• cuts lid quickly
• long lifetime
• non-corrosive blade and geared wheel
• easy to use
• small force required to push lever arm
• aesthetically pleasing

Engineering Specifications

• power consumed (W)
• maximum force exerted on magnet without failure (lbs)
• allowable can height and width (in)
• maximum thickness of lip on lid (in)
• force need to puncture can lid (lbs)
• volume (in^3)
• time it takes to cut standard lid (sec)
• motor lifetime (yrs)
• time it takes for blade to dull (yrs)
• corrosion value (#)
• force required to push lever arm (lbs)
• percentage of customers who like appearance (%)
• number of colors available (#)

Parts

The table belows lists the Bill of Materials for the Durabrand Can Opener:

Table 1: Durabrand Can Opener Bill of Materials

Part #	Part Name	Category	Function	Material	Picture
1	Casing	Structural component	Holds, protects, and supports internal and external components	ABS plastic
2	Guide bar	Support element	Guides lever arm and can	Metal
3	Magnet	Support element	Holds can lid	Ceramics
4	Geared wheel	Output	Rotates can	Metal
5	Cutting blade	Output	Cuts though can lid	Metal
6	Lever arm	Structural component	Holds blade and magnet; on/off switch	Plastic
7	Motor	Input	Rotates the geared wheel	Metal plate, coil
8	Medium gear	Output	Converts the electrical energy into the horizontal mechanical energy	Metal, plastic, and ball bearings
9	Large gear	Transmission	Reduces speed of rotation and provides more torque; connects to geared wheel	Inner gear - metal; outer gear - plastic
10	Switch	Power supply	Completes circuit; on/off switch	Copper with plastic plate (nonconductor)
11	Power cord	Power supply	Supplies power to motor	Wires and insulation with a metal connection

Large Gear and Geared Wheel Module

Decisions:

• type of material
• gear ratio to reduce angular velocity

Critical features:

• radius
• gear tooth size
• life expectancy

Expected loading:

• weight of can

Measures to evaluate performance:

• force exerted on geared wheel
• friction between geared wheel and can
• friction between gear shaft and support structure

Figure 1: Large Gear and Geared Wheel Module

Medium Gear

• Decisions: type of material, high gear ratio to reduce angular velocity
• Critical features: radius, tooth size, life expectancy
• Expected loading: stress
• Measures to evaluate performance: stress, friction of gears, friction of shaft

Motor and Shaft

• Decision: size, power requirement
• Critical features: power output, electrical connection
• Expected loading: resistance of friction and weight of can
• Measures to evaluate performances: torque, speed, lifetime