Problem Statement
The purpose of this wrench is to make it easier to assemble and remove the fuel pump from a VP-44 Cummins ISB 24-valve diesel engine. This would improve the efficiency and frustration of working on these engines.
This assignment covers specific modules of motion. Last Assignment I chose the "best" wrench for the application. This assignment I am exploring different hinge options for the wrench then using a decision matrix
to find the best option.
Updated Assumptions
The wrenches will be used at a constant rate of 1 rad/s, will accept 15mm bolts, are no longer than 10 inches, and are made of a Chromium Vanadium alloy drop forged and plated in chrome. The moment about the hinge
will be calculated to help determine necessary strength at this location.
Activities Date and Time for this assignment:
Gantt Chart
4/18/19 6-9PM: Brainstorm, Create Gantt Chart, Start modeling
4/19/19 6-9PM: Finish modeling, Decision Matrix, Drawings, FRDPAARC
4/20/19 9PM-12AM: Update website, Give Advice
Decision Matrix
The best hinge design was design hinge one, it had the best cost, ease of use, and aesthetics. It had decent Funtionality, but lacks durability.
This hinge has the least number of parts reducing complexity, the tight tolerances make it stiff so the position dsired will be maintained,
and it looks the best because it is press-fit and is more streamlined with the rest of the wrench. This design lacks durability because it is
press fit and the internal mechanism that holds it together will wear out over time faster than a pin or bolt. The other hinges require more parts,
hinge 2 has a range of mobility that is unecessary for the application. Hinge 3 has many parts to increase the functionality and ease of use by allowing
the hinge to lock, however, this makes the part uneccesarily complex.
Solution Concepts
Solution 1
This is a Press fit hinge and is chosen as the best option for the wrench. It has tight tolerances which make provide a large amount of friction. In this
case this is good as the hinge will maintain its position better. A press fit hinge is useful as id does not require a pin as an axis and maintains most of
its strength.
Click Here for files: Solution 1
Solution 2
This is a standard pinned hinge with both sides being opposite symmetrical held in place with a pin. The larger axis allows for a larger range of motion
which is not necessarily a good thing.
Click Here for files: Solution 2
Solution 3
This is a locking hinge almost a cross between the first and second solutionslow tolerance like the first and pinned with a bolt like the second. This one differs
because it offers a bolt and nut mechanism that locks a specified angle in place.
Click Here for files: Solution 3
Static Analysis
FRDPARRC Tables
Lessons Learned
I learned that that it is important to think about the bigger picture, I made the mistake of thinking too narrowly
which made making three concepts very detail oriented making this assignment unnecessarily difficult. If I were to
change something I would have been less specific with my concepts in the second assignment.
To Advisee Antonio Kraychete
Overall very good job, the presentation is clear, simple, and to the point. Maybe you could make your Description under your
decision matrix a little less wordy or display it in a way that is easier on the eye.
To Advisee Daniel Todd
The organization of your website is very good, simple and to the point. Maybe next time you could make your design images
larger I had to open them in a separate tab to read the descriptions. Consider elaborating more on your descriptions.