Power Scissors

Bucknell Mechanical Design Home

Power Scissors Dissection

Figure 1: HP Deskjet 600c Before Disassembly

Figure 2: HP Deskjet 600c Without The Case

Function

The primary function of the Power Scissors is to cut through different materials. There are two blades, the bottom one stays stationary, and the top blade moves rapidly, opening and closing. This action allows the tool to cut through things.

2) Another stepper motor, undocks the printer carriage. The dock is used to secure the carriage, and to keep the printer head clean.

Figure 5: Docking Station For The Carriage

Figure 6: Stepper Motor That Drives The Dock Using A Worm Gear

3) The printer carriage is operated by a drive belt, which is powered by a third stepper motor.

Figure 7: Belt Drive System

Figure 8: Stepper Motor That Drives The Belt Using A Toothed Pulley

4) The printer cartridge applies ink onto the paper according to the instructions supplied by the CPU through the copper contacts.

Figure 9: Cartridge To CPU Interface

Parts

The table belows lists the components for the HP Deskjet 600c printer:

Table 1: Power Scissors Component List

Part #	Part Name	Category	Function	Material	Picture
1	Motor	Input	Serves as Power Supply for blades
2	External Casing	Structural Component	Protects internal components and holds them together	Plastic
3	Jaws	Ouput	The bottom blade remains stationary, while the top blade moves continually up and down	Steel
4	Battery	Input	Provide power to motor	Wrapped in cardboard
5	Cam	Motion Conversion	This forces the bracket to move by translating rotation motion of the motor, to translational movement in the bracket. The bracket then causes the upper blade to open and close	Plastic
6	Screws	Structural	Holds Casing Together	Metal
7	Bracket	Support element	Ball and socket joint limits movement of jaws. The socket is ovular so it allows some movement of the jaws.	Plastic
8	Button (spring)	Motion Conversion	Closes switch to start motor by closing circuit.	Button – plastic Spring – metal Switch - metal User Requirements a. Blades are sharp enough to cut different materials i. Have a sharpening function b. Easy to use i. Has a low weight ii. Has a small size iii. Comfortable to hold iv. Wireless v. Easily accessible buttom to start c. Aestheically Pleasing i. More likely to be bought d. Long battery life, chargeable e. Changeable blades for different materials to cut f. Doesn’t break if dropped Engineering Specifications 1. Material for jaws is sharper than cutting materials strength. This corresponds to E. 2. Battery Life is ______ long. This correspsonds to D. 3. Force of scissors is greater than _____. This corresponds to A. 4. Weight is less than _______ (5 lbs?). This corresponds to B. 5. Scissors retain sharpness for _______ (amt of time). This corresponds to A. 6. torque on motor is ______. This corresponds to A. 7. External casing can withstand ______ force, to avoid being dropped. This corresponds to F. 8. A certain percentage of people when surveyed said that the scissors are pleasing. This corresponds to C.