From DDL Wiki
Ratcheting Screwdriver Parts List
| Part # | Part name | QTY | Function | Wt.(kg.) | Material* | Process* | Photo
|
| 001 | Screwdriver Shaft | 1 | Holds the screwdriver bits in its tip, while the base is connected to the handle. | NA | Aluminum | | | []
|
| 002 | Screwdriver Handle | 1 | Allows the user to grasp the screwdriver for use. | NA | Rubber/Plastic | | | []
|
| 003 | Ring Gear/Ratchet Housing | 1 | Rotates opposite the engaged pawls, and allows for the ratcheting of the screwdriver. | NA | Aluminum | | | []
|
| 004 | Pawl | 2 | Engages the ring gear to stop rotation in one direction, allowing rotation in the opposite direction, thereby allowing ratcheting. both pawls can also be engaged to sllow no ratcheting such that the screwdriver can be used as a regular/static screwdriver. | NA | Steel | | | []
|
| 005 | Pawl Spring | 2 | The spring pushed the back end of the pawl, forcing it to engage the ring gear. | NA | Aluminum | | | []
|
| 006 | Ball Bearing | 1 | Allows free left and right motion of the button. | NA | Aluminum | | | []
|
| 007 | Body Screw | 1 | Attaches the screwdriver shaft to the screwdriver handle. | NA | Steel | | | []
|
| 008 | Button | 1 | Can be switched left, right, or middle, allowing left or right ratcheting or stopping motion. | NA | Aluminum | | | []
|
| 009 | Button spring | 1 | Pushes the ball bearing against the rear of the button. | NA | Aluminum | | | []
|
Portable Screwdriver/Drill Parts List
| Part # | Part name | QTY | Function | Wt.(kg.) | Material* | Process* | Photo
|
| 001 | Screwdriver/Drill Housing | 1 | Houses the internal parts of the drill | NA | Plastic | | | []
|
| 002 | Drill Cover | 1 | Covers the nose of the drill | NA | Plastic | | | []
|
| 003 | Drill Motor | 1 | Rotates the sun gear, draws current through the wires at the base of the motor to determine the direction and speed of rotation | NA | Plastic/Metals | | | []
|
| 004 | Rechargeable Batter Pack | 1 | The power source for the drill, draws power from the battery chargin power input and stores the voltage. | NA | Metal, Plastic, and Chemicals | | | []
|
| 005 | O Ring | 1 | Clamps the drill housing to the drill shaft | NA | Metal | | | []
|
| 006 | Gear Housing | 1 | Acts as a cylindrical ring gear that houses the planetary gear system. | NA | Copper | | | []
|
| 007 | Reset Button | 1 | A button on the external part of the body that will reset the drill when depressed. | NA | Plastic | | | []
|
| 008 | Battery Charging Power Input | 1 | Draws voltage from the power cord and send it to the rechargeable battery pack where it is stored. | NA | Plastic/Metal | | | []
|
| 009 | Large Housing Screws | 2 | Holds the plastic housing together | NA | Steel | | | []
|
| 010 | Small Housing Screws | 3 | Holds the plastic housing together | NA | Steel | | | []
|
| 011 | Trigger | 1 | Houses the internal parts of the drill | NA | Plastic | | | []
|
| 012 | Washer | 1 | Houses the internal parts of the drill | NA | Plastic | | | []
|
| 013 | Planetary Gears | 1 | Houses the internal parts of the drill | NA | Plastic | | | []
|
| 014 | Sun Gear | 1 | Houses the internal parts of the drill | NA | Plastic | | | []
|
| 015 | Intermediate Gears | 1 | Houses the internal parts of the drill | NA | Plastic | | | []
|
| 016 | Drill Shaft | 1 | Houses the internal parts of the drill | NA | Plastic | | | []
|
| 017 | Lights | 1 | Houses the internal parts of the drill | NA | Plastic | | | []
|
| 018 | Wiring | 1 | Basic red and black wires running current between electrical parts of the drill | NA | Plastic/Copper | | | []
|
Mechanical Analysis
Analysis of the Gear Ratio for the Electric Screwdriver:
The electric motor within the electric screwdriver produces a very high rotational speed, but very little torque. However, the customer needs a device capable of producing a relatively high amount of torque, but not necessarily at such a high speed. Thus, the electric motor is geared down before it is attached to the bit. After the dissection of the drill, we found that a planetary gear system was used to accomplish this.
In this gear train, the annulus was held stationary within a housing. The sun gear was used for the input, and the output was therefore the planet carrier. This planet carrier in turn was connected to the sun gear for the next level. In total there were three levels of gears, each of which reduced the torque by a factor of 1/(1+A/S), where A is the number of teeth on the annulus, and S is the number of teeth on the sun gear. With three levels, the total gear ratio is 1/(1+A/S)^3.
