Group 15 - Craftsman 32 cc String Trimmer (Model

From GICL Wiki
Jump to: navigation, search
{{#if:Craftsman 32cc Weedwhacker||}} {{#if:|}}{{#if:|}}{{#if:|}}{{#if:weedwacker.jpg |}}{{#if: |}}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: Craftsman | }}{{#if: | }}{{#if: | }}{{#if: Approx 140.00 | }}{{#if: | }}{{#if: | |{{#if: | }}}}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | |}}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if: | }}{{#if:|}}{{#if:|}}
Craftsman 32cc WeedwhackerGroup 15 - Craftsman 32 cc String Trimmer (Model
{{{above}}}
{{{subheader2}}}
Error creating thumbnail: convert: no decode delegate for this image format `/tmp/magick-Ogjrgpxb' @ error/constitute.c/ReadImage/532.
convert: missing an image filename `/tmp/transform_1494b1463a31-1.jpg' @ error/convert.c/ConvertImageCommand/3011.
{{#if: |
}}
[[Image:|{{#if:|px|125px}}|]] {{#if: |
}}
Author [[User:{{{author_user}}}|{{#if:{{{author_name}}}|{{{author_name}}}|{{{author_user}}}}}]]warning.png"{{{author_user}}}" cannot be used as a page name in this wiki.
Organization {{{organization}}}warning.png"{{{organization}}}" cannot be used as a page name in this wiki.
Name of Artifact
Manufacturer Craftsman
Built in {{#if: |{{#if: |, }}|}}{{#if: |{{{bldstate}}}warning.png"{{{bldstate}}}" cannot be used as a page name in this wiki.{{#if: |, }}|}}{{#if: |{{{bldcountry}}}warning.png"{{{bldcountry}}}" cannot be used as a page name in this wiki.|}}
Assembled in {{#if: |{{#if: |, }}|}}{{#if: |{{{asmstate}}}warning.png"{{{asmstate}}}" cannot be used as a page name in this wiki.{{#if: |, }}|}}{{#if: |{{{asmcountry}}}warning.png"{{{asmcountry}}}" cannot be used as a page name in this wiki.|}}
Cost Approx 140.00 USD
Number of Parts {{{numparts}}}warning.png"{{{numparts}}}" cannot be used as a page name in this wiki.
Required Tools warning.png"" cannot be used as a page name in this wiki.
  {{{tool2}}}warning.png"{{{tool2}}}" cannot be used as a page name in this wiki.
Required Tool {{{tool}}}warning.png"{{{tool}}}" cannot be used as a page name in this wiki.
  {{{tool3}}}warning.png"{{{tool3}}}" cannot be used as a page name in this wiki.
  {{{tool4}}}warning.png"{{{tool4}}}" cannot be used as a page name in this wiki.
  {{{tool5}}}warning.png"{{{tool5}}}" cannot be used as a page name in this wiki.
Behavioral Elements
 
 
Materials and Production Processes
  {{{process1.2}}}warning.png"{{{process1.2}}}" cannot be used as a page name in this wiki.
  {{{process1.3}}}warning.png"{{{process1.3}}}" cannot be used as a page name in this wiki.
  {{{process2.2}}}warning.png"{{{process2.2}}}" cannot be used as a page name in this wiki.
  {{{process2.3}}}warning.png"{{{process2.3}}}" cannot be used as a page name in this wiki.
  {{{process3.2}}}warning.png"{{{process3.2}}}" cannot be used as a page name in this wiki.
  {{{process3.3}}}warning.png"{{{process3.3}}}" cannot be used as a page name in this wiki.
  {{{process4.2}}}warning.png"{{{process4.2}}}" cannot be used as a page name in this wiki.
  {{{process4.3}}}warning.png"{{{process4.3}}}" cannot be used as a page name in this wiki.
  {{{process5.2}}}warning.png"{{{process5.2}}}" cannot be used as a page name in this wiki.
  {{{process5.3}}}warning.png"{{{process5.3}}}" cannot be used as a page name in this wiki.
  {{{process6.2}}}warning.png"{{{process6.2}}}" cannot be used as a page name in this wiki.
  {{{process6.3}}}warning.png"{{{process6.3}}}" cannot be used as a page name in this wiki.
  {{{process7.2}}}warning.png"{{{process7.2}}}" cannot be used as a page name in this wiki.
  {{{process7.3}}}warning.png"{{{process7.3}}}" cannot be used as a page name in this wiki.
UNSPSC Codes
{{#if: || }}
{{#if: || }}
{{#if: || }}
{{#if: || }}
{{#if: || }}
SUMO Entries
warning.png"" cannot be used as a page name in this wiki.
{{{sumo2type}}} {{{sumo2}}}warning.png"{{{sumo2}}}" cannot be used as a page name in this wiki.
{{{sumo3type}}} {{{sumo3}}}warning.png"{{{sumo3}}}" cannot be used as a page name in this wiki.
{{{sumo4type}}} {{{sumo4}}}warning.png"{{{sumo4}}}" cannot be used as a page name in this wiki.
{{{sumo5type}}} {{{sumo5}}}warning.png"{{{sumo5}}}" cannot be used as a page name in this wiki.
{{{sumo6type}}} {{{sumo6}}}warning.png"{{{sumo6}}}" cannot be used as a page name in this wiki.
{{{sumo7type}}} {{{sumo7}}}warning.png"{{{sumo7}}}" cannot be used as a page name in this wiki.
{{{sumo8type}}} {{{sumo8}}}warning.png"{{{sumo8}}}" cannot be used as a page name in this wiki.
{{{sumo9type}}} {{{sumo9}}}warning.png"{{{sumo9}}}" cannot be used as a page name in this wiki.
{{{sumo10type}}} {{{sumo10}}}warning.png"{{{sumo10}}}" cannot be used as a page name in this wiki.
NIST Functional Basis Elements
warning.png"" cannot be used as a page name in this wiki. warning.png"" cannot be used as a page name in this wiki.
Included File Formats
warning.png"" cannot be used as a page name in this wiki.{{#if:|| }}
{{#if:|| }}
{{#if:|| }}
{{#if:|| }}
{{#if:|| }}
 [[[|v]]  [[|d]]] 

Contents

Introduction

Product Proposal

Introduction

The product we would like to request for our presentation and dissection is a string trimmer, or most commonly known as a weed whacker. The string trimmer is a handheld yard tool, which usually uses a nylon string for cutting grass and other small shrubbery near objects. The string trimmer is a very common product, has great utility for homeowners and landscapers, is easy to transport, and is available in different types and a variety of brands and models. The three types of string trimmers you may find differ primarily by their power supply, and these power supplies can be electric, a two-stroke gasoline engine, or a four-stroke gasoline engine.

With you now a bit more familiarized with string trimmers, we would like to dive deeper into the many ways they affect and influence the world. From there we will discuss the mechanics of the device and some of the main components they require for operation. To conclude our discussion, we will discuss our plans on how we will acquire a string trimmer.

Four Factors Directly Impacting the Design

A. Global Factors

String trimmers are not tools that are made generally for everyone, because not everyone uses them the same amount or way. With that being said weed whackers are designed for a variety of different consumers. Starting from the top the best quality string trimmers are built with durability and power in mind, capable of handling the toughest jobs with no complications. These string trimmers are often considered commercial grade and are usually purchased by landscapers or the more serious lawn enthusiasts. Following commercial and non-commercial grade string trimmers, which are divided into several categories. There are electric string trimmers which come in which you have the option of cordless battery operated or a corded non-battery operated. These string trimmers are competitively priced along with gas powered string trimmers offering similar performance to other noncommercial grade string trimmers, however corded string trimmers can be unwieldy for large landscapes and battery powered string trimmers are unreliable for large yards. The gas powered string trimmer is ideal for someone with a rather large yard, which may require continuous operation of use in changing weather conditions. Gas powered string trimmers vary largely in quality and price depending on the manufacturer and added features.

B. Societal Factors

During the design of almost any product, safety is a number one concern. String trimmers are no exception to this design principle. It is clear just by looking at a string trimmer that the engineers and designers involved with making this product wanted to make sure that the average consumer would be able to safely operate and maintain their it without ever coming into harm’s way. Several safety features I noticed on the various string trimmers I observed were:

1) Metal guard – The metal guard is located on the bottom of the string trimmer above the cutting wheel. This is used to protect the user from any potentially hazardous debris that may ricochet towards them.

2) Nylon cutting blades – This probably does not sound like a safety feature at first, however in the worst case scenario that at some point the nylon cutting blades did make contact with a user’s leg (which should be protected by long pants or jeans as per the instruction manual) the leg would be injured however it would also be intact. If one were to replace the nylon blades with a metal blade or metal chains, the same could not be guaranteed. This trade off of a long lasting blade to safety was without a doubt one which was made with the consumer’s safety in mind.

3) Rubberized handle/grip – Although not every model we researched had a rubberized handle and grip the ones that did offer this feature definitely did them not only for comfort but also to ensure the consumer will have a firm grip of the string trimmer throughout its operation. Not everyone who takes care of his or her lawn is a savant of lawn care or an expert of power equipment. The average consumer, the person who is most likely to buy a string trimmer may have moderate to no experience with power equipment. In the case of the gas engine string trimmers especially it is almost impossible to guarantee the life of the equipment without routine maintenance. This routine maintenance includes but is not limited to; changing the cutting blades, checking/changing the oil (4-stroke engines only), replacing/re-oiling the air filter (gas powered only), checking/replacing spark plugs, adjusting the idler, and adding the required oil to gas mix for 2-stroke engines. All of these things must be engineered and designed with the average consumer in mind. For example, checking the oil level or replacing the filter should not require opening the engine; it must be something that can readily be done with few or no tools.

C. Economic Factors

String trimmers today are developed to be economically accessible to a variety of consumers. The top end models are the most expensive but will have the best durability and most features, moderately priced models will often sacrifice some of the durability to compensate for the lower price while the lower end models will have the lowest price as well as lowest durability. Often times the one thing that truly separates the top end from the lower end models is the material and design features that ensure a long product lifespan. Most of the more expensive models typically have features such as a die-cast clutch covers to reduce vibration, engine management system for better fuel economy and increased power, and a design that optimizes the ergonomics of the product. A design that is becoming increasingly popular for string trimmers is to develop the weed whack around a power head that is capable of being attached to several different elements used for lawn care. Some attachments include a brush cutter, edger, chain saw, hedge clipper and/or a brush. The idea behind this innovation is to reduce the tools needed in lawn care by synchronizing as many tools into one device. From an economic standpoint this benefits both the company and the consumer because it lowers the cost of the tools and creates less waste. By purchasing a string trimmer/power head combo people are allowed to condense many simple yard tools into one affordable package as opposed to many expensive ones.

D. Environmental Factors

Similarly to automobile engines, small 2-stroke and 4-stroke engines must comply with the emissions standards set by the environmental protection agency as well as any locally enforced restriction on emissions (California’s CARB compliance). In order to accomplish this task engineers must design an engine that is not only low on emissions but also powerful enough to complete a job in a reasonable amount of time while creating as little noise pollution as possible.

E. Summary

Hopefully by this part it is clear that there are a variety of factors that go into consideration when engineers were designing a string trimmer. From safety concerns to emissions standards there are a plethora of factors that engineers need to consider before they can even design a product. By carefully mapping these factors engineers are able to layout the groundwork for the design process.

Components and Sub-systems

A string trimmer can be broken down into four main subsystems; they are the energy source, the energy converter, power transfer, and power output. These subsystems can be used for any type of string trimmer. For the energy source of the trimmer the possibilities are electricity from ether a power cord, a battery, or gasoline for the four and two-stroke engines. The energy converter is the engine for the gas powered trimmers and the motor for the electric trimmer. Power transfer is how the rotational force is transferred from the converter to the cutting head. Finally the power output for the trimmer is the cutting head where the power produced is used to accomplish the desired goal.

How it stays together / drive shaft cover-The handle that is a tube for the drive shaft to spin in and a soft grip to lessen the vibration from the engine.A handle of plastic that the drive shaft runs through and that acts as the handle.A handle of plastic that the drive shaft runs through and that acts as the handle.

Safety-A shield facing the operator of the machine to stop debris from hitting him or her also a heat shield around the engine. A shield facing the operator of the machine to stop debris from hitting him or her. A shield facing the operator of the machine to stop debris from hitting him or her.

We would like to know what kind of energy transfer the particular string trimmer has, whether it be a four-stroke, two-stroke gasoline, or an electrical trimmer. By doing so, we can figure out how much power is lost throughout the entire transfer, and what we can do to make it more efficient. This would help at an economic standpoint because whichever string trimmer we are using, it can save electricity or gas. We would also like to study a power vs. RPM graph, to optimize the cutting speed with the power band. Trying to improve on this would not only help economically, but also help from a societal standpoint due to fuel or power consumption being lowered. This would help greatly in a world where fossil fuels are running low, and the average consumer has to worry about their power bill. In order to dissect the product, we will need certain tools. A string trimmer consists of parts put together by mainly screws. Therefore, we are going to need a flat head screwdriver along with a Phillips head. To accompany this, we would also need a socket set in case we ran into any problems during dissection. IV. Product Acquisition Our intention is to have the department provide our group with a string trimmer. A functional string trimmer can be purchased second hand through craigslist, yard sale, or local second hand equipment supply shop ranging from as low as $15 - $50. In the event our group pays for the string trimmer we will split the cost equally 5 ways equaling a sum of no more than $10 per person. Any option for ownership is voided if the department pays for the string trimmer. In this case, upon completion of our assignment we will return the string trimmer to the department in the condition it was received. In the event our group pays for the string trimmer, we have decided to sell and split the money received or we will donate the string trimmer to the UB engineering department.

Conclusion

String trimmers are a relatively simple system from the outside, however once taken apart and dissected, they quickly evolve into a complex device, with various systems, subsystems, and components. If given the privilege of studying a string trimmer for our group assignment we will thoroughly demonstrate our knowledge of the various aspects of a string trimmer and how these aspects directly relate to engineering. By dissecting and reassembling a string trimmer our group would be able to analyze first-hand the ideas that were implemented by engineers. This would be the first time that most of us have ever been faced with such a task. This will only serve as invaluable experience further down the road as many of us go on to study the design aspects of engineering.

Group Members

Name Email Job Title
Courtney Scott cescott3@buffalo.edu Project Manager
Behzad Rustemi behzadru@buffalo.edu Research and Analysis
Matthew Hervan mghervan@buffalo.edu Lead Wiki Editor
Jonathan Roche jcroche2@buffalo.edu Communication Lead and Editor
George Melero gamelero@buffalo.edu Chief Mechanic

Gate 1

Gate 1-Contains Product Management and Archaeology Profiles