crusher simple machine

7/26/2019 Crusher simple machine

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Straight-6Crusher

By:

Kendrick Lau

Michael Signorelli


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Table of Contents

Project Introduction ............................................................................................................................. 3

Design Background............................................................................................................................... 4

Spec Sheet ................................................................................................................................................ 6

Assembly Configuration ...................................................................................................................... 7

Position Synthesis and Analysis ..................................................................................................... 11

Kinematics Analysis ........................................................................................................................... 12

Dynamic Analysis ................................................................................................................................ 15

CAD Verification .................................................................................................................................. 17

Force Analysis ...................................................................................................................................... 20

Animation .............................................................................................................................................. 22

Finite Element Analysis..................................................................................................................... 23Piston ................................................................................................................................................................. 23Connecting Rod ............................................................................................................................................... 27Crank .................................................................................................................................................................. 30Wheel ................................................................................................................................................................. 34

Optimization ......................................................................................................................................... 37

Conclusion ............................................................................................................................................. 40

Appendix ................................................................................................................................................ 412D Drawings .................................................................................................................................................... 41Exploded Views .............................................................................................................................................. 48


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Project Introduction

Recycling is an important aspect of todays society and its purpose cannot be overlooked, as

its effects are widespread. It is one of the simplest things a person can do to make an

impactful difference. Among its effects, recycling saves the environment by reducing the

reliance on landfills and incinerators, saves energy by providing useable materials for newproducts, and also saves natural resources from being made into landfills. As such, it is not

difficult to understand why recycling has become such an important aspect of today s

society.

Beverages also play a big part in todays society as almost a quarter of all popular

beverages consumed in the US come from soda cans. It is equally important to recycle soda

cans as it is any other recyclables, but soda cans present an interesting case as they are

typically crushed to save space. This is easily done for a small amount of cans, but proves to

be a daunting task if there are too many cans. Additionally, the force required to crush a can

and the accuracy required to crush a can proportionally add to the difficulty of crushing a

can.

This is where the importance of can crushers comes into play. A properly designed can

crusher uses mechanical advantage to moderate the input from a user to a comfortable

level, as well as ensuring that a can is properly crushed. This is the motivation for this

project.


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Design Background

The design motivation for the can crusher comes from a car engines design. One of the

main components of a car engine is the cylinder, where pistons move back and forth in a

chamber during the combustion process. The can crusher design is based on this engine

components design and uses the pistons to crush the cans. Mechanically, this is classifiedas a crank-slider since a crank directs the pistonsup- and downward motion. The crank

and piston are connected by a connecting rod, completing the crank-slider configuration. In

this scenario, the crank serves as a crank and the piston serves as the slider. The

connecting rod serves as the link between the two, while the ground is the rest of the

design.

The crankshaft, connecting rod, and pistons are all designed in the can crusher as they are

in an engine. The crankshaft is connected to an external gear and controls the overall

motion of the individual cranks. The connecting rod is made up of six parts - the rod, the

bottom connecting part of the rod, and the nuts and bolts required to connect the two. The

piston is designed as two parts the piston itself and a bolt to hold the piston in place on

the connecting rod.

In our can crusher design, the crankshaft has six individual cranks that control the pistons

in six different chambers. This allows for the can crusher to crush six cans in one process

a design cue based on the fact that cans are usually bought in a six-pack. This is also

motivated by the fact that it will save the user work by crushing six cans in one process, as

opposed to crushing cans individually, which is more time-consuming. The can crushers

six-chamber design is unlike a typical engines six-chamber design, which is designed with

a V-format; instead, the can crusher is designed in an inline format where the six chambers

form a line with each other. Visually, this is comparable to an inline-4 engine, except that

there are two extra chambers.

Further, the crankshaft is designed such that only two pistons are operating at the same

position at the same time. This is due to the 120-degree separation between the individual

cranks. As such, there are three pairs of cranks and each pair operates at the same position.

Thus, at any given time, at most two cans are crushed simultaneously. This design cue was

implemented to reduce the amount of force required to crush the cans. The position

analysis is explained further below in the Position Analysis section.

The can crusher is operated by turning a steering wheel that is internally connected to the

crankshaft. As expected, the wheel is turned in a rotational manner. Only one full 360-degree turn is required to crush the cans in all six chambers.

The cans are loaded from the side by placing them into the chambers and are unloaded in

this same manner. Unloading requires some maneuvering of the steering wheel, as the

configuration does not allow for all six pistons to be located in the same position at any

given time. As explained above, this is due to the crank angles. At most, four pistons can be


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positioned at the top together, and then the remaining two pistons can also be positioned

together at the top.

Finally, the rest of the can crusher is also designed to replicate an engine. For example,

there are a couple valves at the top of each chamber and a cam that spreads across the

entire configuration. Overall, the casing has a glass cover to display the internals andoperation of the can crusher.

The entire assembly is shown below.

Figure 1. Assembly.


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Spec Sheet

Height 722 mm

Width 660 mm

Length 200 mm

Capacity of Can Crusher 6 cans

Force Required to Crush Can 450 N

Torque Required to Turn Wheel 61,200 N-mm

Material ABS Plastic for Piston

Aluminum 6061 for Connecting

Rod, Crank and CasingTable 1. Specification Sheet.


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Assembly ConfigurationIn order to get the crank-slider configuration of the can crusher, three separate parts had to

be created: the crankshaft with six separate cranks, the connecting rod, and the piston. The

first part of the assembly is the crankshaft with six separate cranks. It is shown below. The

casing is used as a ground and the crankshaft is connected to it. It is shown below:

Figure 2. Crank Assembly with Casing.

From there, the connecting rods are added to the assembly. The connecting rods are not

fully constrained so that they can move. However, they will be constrained such that thereare four separate conditions. First, the interior circular edge of the connecting rod must be

inserted into the circular edge of the crank. Second, the edge of the connecting rod must be

mated to the edge of the crank. Both of these constraints are shown below:

Figure 3. Constraints of Connecting Rod.

One last constraint set has to be added in order to constrain the connecting rod properly,

which is to constraint a defined point on the connecting rod to the front plane of the

assembly. By doing so, the connecting rods motion is constrained to one up and downward


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motion that is parallel to the front plane of the assembly. Thus, all six cranks will be

operating in the same direction relative to each other. This is shown below:

Figure 4. Final Constraint of Connecting Rod.

Now, it is time to add the piston into the assembly. The piston is constrained using three

constraints. First, the piston top is oriented with the assembly plane that the connecting

rod is aligned with. Second, the pistons circular edge is inserted into the circular edge on

the connecting rod. Third, the pistons edge is offset with the connecting rods edge such

that it is aligned in the middle of the rod. The pistons three constraints are shown below:

Figure 5. Piston Constraints for Assembly.


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To constrain the piston, a piston bolt is required. The piston bolt was constrained using two

constraints to place the bolt inside the piston and the connecting rod. First, the piston had

to be inserted inside the piston and connecting rod. Second, the pin surface had to be

aligned coincident to the piston surface. The two constraints are shown below:

Figure 6. Piston Bolt Constraints for Assembly.

Once these parts are connected, one crank-slider is completed and this process is repeated

for the other five crank sliders as well. Below is a picture of the final assembly with all six

crank-slider can crushers in place:

Figure 7. Completed Assembly of the Crank-Slider.


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The remaining parts of the can crusher are added, such as the valves, the gears, and the

wheel to complete the final assembly of the can crusher. However, this is the completion of

the crank slider assembly, which is the main component of the can crusher.


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Position Synthesis and Analysis

In order to find the link lengths of the crank slider, a position analysis technique was used

and backwards engineered to find link lengths. Since a crushed cans height is assumed to

be approximately 30mm while its full height assumed to be 130mm, a 100mm difference

between the fully crushed position (2at 30 degrees) and loading position (2at 60degrees). With this information, the radius of the crank was set at 125mmand the

connecting rod length was to 200mm.

The following equations were used to solve for position analyses:

Since 1is constant and equal to 0, the equations simplify. They were also then separated

into the real and imaginary counterparts:

Real Component:

Imaginary Component:

This gives the resulting equations used in the analysis:

2[] 3[] Distance from

Origin [mm]

Displacement from Loading

Height [mm]

0 0 325 94.3

30 -18.2 298 67.6

60 -32.8 231 0

90 -38.7 156 -74.5

120 -32.8 106 -125

150 -18.2 81.7 -149

180 0 75.0 -156210 18.2 8.7 -149

240 32.8 106 -125

270 38.7 156 -74.5

300 32.8 231 0

330 18.2 299 67.6

360 0 325 94.3Table 2. Output angle and Distance as a function of Input.


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Figure 8. Displacement Graph

Kinematics Analysis

Once the position was known as a function of the input angle, the velocity could be found.

Since the kinematics rely on an input angular velocity, one was approximated. An angular

velocity of 2.09 rad/s was used because this correlates to 1 revolution in 3 seconds.The

same vector approach was used:

Using the same derivative and vector approach used in the position and velocity analyses, it

is possible to find the acceleration of the piston as a function of the input angle:

0

50

100

150

200

250

300

350

0 100 200 300 400

DistancefromO

rigin[mm]

Input Angle [deg]

Position of Crank Slider

Distance From Origin

Crush Zone


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2[] Velocity of Piston

[m/s]

Acceleration of Piston

[m/s2]

0 0 -0.891

30 -0.205 -0.685

60 -0.311 -0.112

90 -0.261 0.439

120 -0.142 0.436

150 -0.0563 0.265

180 0 0.205

210 0.0563 0.265

240 0.142 0.436

270 0.261 0.439

300 0.311 -0.112

330 0.205 -0.685360 0 -0.891

Table 3. Velocity and Acceleration of the Piston.


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Figure 9. Velocity of Piston

Figure 10. Acceleration of Piston

-400

-300

-200

-100

0

100

200

300

400

0 50 100 150 200 250 300 350 400

Velocity[mm/s]

Input Angle [deg]

Velocity of Piston

-1000

-800

-600

-400

-200

0

200

400

600

0 50 100 150 200 250 300 350 400

Velocity[mm/s^2]

Input Angle [deg]

Acceleration of Piston


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Dynamic Analysis

Since there is more than one piston revolving at a time, it is important to look at how all the

pistons interact with one another. In order to do this, three of the six (since the other three

are mirror images) pistons were analyzed and their graphs were superimposed.

Figure 11. Displacement Plot as a function of time.

Figure 12. Velocity Plot as a function of time.

0

50

100

150

200

250

300

350

0 0.5 1 1.5 2 2.5 3 3.5

Displacement[mm]

Time [s]

Displacement Plot

Piston 1

Piston 2

Piston 3

-400

-300

-200

-100

0

100

200

300

400

0 0.5 1 1.5 2 2.5 3 3.5

Velocity[mm/s]

Time [s]

Velocity Plot

Piston 1

Piston 2

Piston 3


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Figure 13. Acceleration Plot as a function of time.

-1000

-800

-600

-400

-200

0

200

400

600

0 0.5 1 1.5 2 2.5 3 3.5

Acceleration[mm/s^2

]

Time [s]

Acceleration Plot

Piston 1

Piston 2

Piston 3


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CAD Verification

After hand solving for the kinematics of the crank slider, the assembly was studied in

Pro/Engineer Wildfire 5.0s Mechanism package. Three different measures were defined at

the ends of each piston. The mechanism was run at the same angular velocity as mentioned

above and the graphs were compared. There were no deviations other than scaling. Thiswas because of where Mechanism took its reference point. Because of this all results were

valid.

Figure 14. Mechanism Displacement Plot.


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Figure 15. Mechanism Velocity Plot.


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Figure 16. Mechanism Acceleration Plot.


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Force Analysis

In order to make sure the mechanism would not fail, both hand calculations and finite

elemental methods were used to verify the Factor of Safety of the mechanism. The assumed

amount of force needed to crush a can is 450 N. In order to effectively evaluate the

maximum forces in the mechanism, it is important to find the angle at which there will bethe most stress. This angle was determined to be the angle when a can begins crushing.

After performing the calculations, the mechanism was found to have a factor of safety of

8.08.

The equations used to solve the force matrix are shown below.

Link 2:

Link 3:

In order to more accurately solve for the position vectors in the above equations,

Pro/Engineer was used to find where the center of mass was located. These values are

shown below:

R_12 78 mm

R_32 47 mm

R_23 71 mm

R_43 129 mmTable 4. Centers of mass for the links

Because the most critical loads are found at the angle when the can begins to crush, this

was the only angle that was observed. The results for this calculation can be found below.

The matrix used can be seen in the calculations appendix.

Measurement Load

F_43_x -450 N

F_43_y -290 N

T 30.6 NmTable 5. Important results from Force Analysis


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From the X and Y components of F32, it can be found that the resultant force at the

connecting rod connection is approximately 535 N at a 65angle. This was then imported

into the FEA package for analysis.

These results also show what the required torque needed to crush the cans is. The torque

found is needed to crush one can. However, in this design, two cans are crushed at a time.Thus, the required torque is 61.2 Nmto smash the cans. This was also imported into the

FEA package for analysis.

Knowing the required torque was extremely helpful for designing the wheel because it

helped determine the force input on the wheel. Because the wheel has a diameter of 350

mm, the required force per hand to crush the can is 87 N .


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Animation

The animation was created using Pro/Engineer, Animation mode. The animation starts

with various views of the can crusher. The animation then shows the can crusher in

operation before changing into an exploded view.

The animation can be found on an attached external drive.


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Finite Element AnalysisFinite element analysis was done in Pro/Engineer using Pro/Mechanica. Each part of the

can crusher was analyzed individually and the results are shown below.

Piston

The piston was analyzed using a 100 lb force on the top. Constraints were placed on bothcircular edges of the piston and the piston was assigned a material of ABS plastic. The

following picture shows the setup in Pro/Mechanica of the piston for FEA.

Figure 17. Set-up in Pro/Mechanica of Piston for FEA.

Parameter Description

Force 450 N on piston top

Constraints Fully constrained at circular edges

Material ABS Plastic

Mesh refinement

techniques used Volume Regions (3)

AutoGEM controls (2)- Edge distribution, 30 nodes

- Edge exclusion

Analysis Static Analysis using 9 passes at

1% convergenceTable 6. FEA Set-up of Piston in Pro/Mechanica.


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After setting up the piston in Pro/Mechanica, a static analysis was run. A multi-pass

analysis was set up using 9 passes with 1% convergence.

Because of the nature of the pistons geometry, the static analysis did not converge on the

first try. This is because there were a few singularities that caused a spike in analysis. When

performing FEA, this means that the mesh is not refined enough. As such, to refine themesh, we created volume regions and used AutoGEM controls. Three volume regions were

created around the area where the pistons shape changes. Two AutoGEM controls were

used: one to exclude the edges between the top and bottom of the piston and one to create

an edge distribution surrounding the volume regions. This created a finer mesh for

analysis. The volume regions and AutoGEM controls are shown below:

Figure 18. Volume Regions used for Piston


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Figure 19. AutoGEM controls used.

Once the mesh was refined and the singularities were handled, the analysis converged

properly. As shown in the figure below, the maximum von Mises stress occurs at the

pistons circular entrance at a value of 4.349 MPa. Given ABS plastics yield strength of

35.163 MPa, the piston has a safety factor of 8.08.

Figure 20. Fringe Plot of the Piston's Von Mises Stress.

To verify that the correct VMS was achieved by the analysis, the graph of the VMS value

versus pass is shown below. The fact that the value tails off and plateaus verifies that

convergence was achieved.


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Figure 21. VMS Convergence of Piston FEA.

Also shown below is the fringe plot of the displacement of the piston. This graph shows

how the piston is displaced when undergoing 100lb of force. The piston only deforms amaximum of 0.001506mm at the bottom, which is extremely small.

Figure 22. Fringe Plot of the Piston's Displacement.

Measure Value

Maximum VMS 4.349 MPaYield Strength 35.163 MPa

Safety Factor 8.08

Maximum Displacement 0.1506 mmTable 7. FEA Results of Piston in Pro/Mechanica.


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Connecting Rod

The connecting rod was analyzed using a 267.5 Newton force on the piston connection.

Constraints were placed at the rod to crank connection and on the neck. The material

assigned to the connecting rod is Aluminum 6061. The following picture shows the setup in

Pro/Mechanica of the piston for FEA.

Figure 23. Set-Up of Connecting Rod in Pro/Mechanica for FEA.


Force 267.5 N at rod to piston connection

Constraints Fully constrained at rod to crank connection; constrained

at the neck to prevent extension

Material Aluminum 6061

Pro/Mechanica

Techniques Used Rigid links (2)

- One for load

- One for constraints Modeled as a half-model to take advantage of symmetry

AutoGEM controls (1)

- Edge exclusions

Analysis Static Analysis using 9 passes at 1% convergenceTable 8. FEA Set-up of Connecting Rod in Pro/Mechanica.


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A few FEA tricks were used to set up the connecting rod in Pro/Mechanica. Rigid links

were used to translate the force and the constraints onto the connecting rod. At the piston

connection end, a force was placed on a point in space and connected to the connecting rod

by a rigid link. At the crank connection end, a constraint was placed on a point in space and

connected to the connecting rod by rigid link. Both of these rigid links transferred the force

and constraints to the connecting rod.

Additionally, the connecting rod was modeled using symmetry. Because the force and

constraints are symmetrical about an axis, the connecting rod can be modeled as a half-

model, as long as the force is modeled at half magnitude.

AutoGEM controls were also used at singularity points to ensure analysis convergence.

Similar to the pistons FEA, the mesh was not refined enough without AutoGEM control.

Once the mesh was refined, the analysis properly converged. The results are below.

As shown in the figure below, the maximum von Mises stress occurs at the connecting rods

neck at a value of 21.99 MPa. Given Aluminum 6061syield strength of 206 MPa, the pistonhas a safety factor of 9.36.

Figure 24. Fringe Plot of the Connecting Rods von Mises Stress.


versus pass is shown below. The fact that the value tails off and plateaus verifies that

convergence was achieved.


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Figure 25. Convergence Plot of the Connecting Rod's FEA.

Also shown below is the fringe plot of the displacement of the connecting rod. This graph

shows how the effect of the force on the connecting rod. As can be seen, the connecting rod

deforms as expected to the right at a magnitude of 0.1609 mm.

Figure 26. Fringe Plot of Connecting Rod's Displacement.

A summary of the results is shown below:

Measure Value

Maximum VMS 21.99 MPa

Yield Strength 206 MPa

Safety Factor 9.36

Maximum Displacement 0.1609 mmTable 9. FEA Results of Connecting Rod in Pro/Mechanica.


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Crank

The crank was analyzed using a 61200 N-mm torque on the end. Only one crank was

analyzed, since the cranks are all the same. As such, constraints were placed on the cranks

next to the analyzed crank. The assigned material of the crank is aluminum 6061. The

following picture shows the setup in Pro/Mechanica of the crank for FEA.

Figure 27. Set-up in Pro/Mechanica of Crankshaft for FEA.


Force 6.12e4 mm-N torque placed on shaft

Constraints Fully constrained on middle two cranks


Pro/Mechanica

Techniques Used Weighted link (1)

- To transfer the torque to the surface of the

shaft Filleted edges (24) at each crank connection

to get rid of singularities

Analysis Static Analysis using 9 passes at 1% convergenceTable 10. FEA Set-up of Crank in Pro/Mechanica.

In order to set up the torque onto the crankshaft, it was necessary to use a weighted link.

This is because the torque is on the surface of the crankshaft, thus necessitating the use of a


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weighted link. To do this, a torque was placed on a point and then it was connected to the

surface using a weighted link.


analysis was set up using 9 passes with 1% convergence.

Because of the nature of the cranksgeometry, the static analysis did not converge on the

first try. This is because there were a few singularities that caused a spike in analysis. In

this case, the singularities are present in the connections between the cranks since the

edges are sharp. As such, the solution was to fillet the edges between all six cranks. This led

to 24 rounds, and this feature is shown in the figure below:

Figure 28. Rounds in Crankshaft for FEA.

The following figures show the analysis results. As shown in the figure below, the

maximum von Mises stress occurs at the cranks connections. The VMS has a maximum of

7.346 MPa. Given Aluminum 6061syield strength of 206 MPa, the piston has a safetyfactor of 28.0.


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Figure 29. Fringe Plot of the Crankshafts Von Mises Stress.


versus pass is shown below. The VMS appeared to converge around Pass 3 but continued to

teeter around 7.00 MPa before finally converging in Pass 9.

Figure 30. VMS Convergence of Crankshafts FEA.

Also shown below is the fringe plot of the displacement of the crankshaft. This fringe plot

shows how the crankshaft is displaced when undergoing force. The crankshaft only

deforms a maximum of 0.1449 mm at the extremity, which is extremely small and naked to

the eye.


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Figure 31. Fringe Plot of the CrankshaftsDisplacement.


Measure Value



Safety Factor 28.0

Maximum Displacement 0.1449 mmTable 11. FEA Results of Crank in Pro/Mechanica.


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Wheel

The wheel was analyzed using a 61200 N-mm torque. The wheel is an extension of the

crank, and as such, undergoes the same amount of torque. Constraints were placed on the

back of the wheel and the assigned material of the wheel is aluminum 6061. The following

picture shows the setup in Pro/Mechanica of the wheel for FEA.

Figure 32. Set-up in Pro/Mechanica of Wheel for FEA.


Force 6.12e4 mm-N torque distributed along entire

wheel

Constraints Fully constrained in the center


Pro/Mechanica

Techniques Used Weighted link (1)

- To transfer the torque to the surface of theentire wheel

Analysis Static Analysis using 9 passes at 1% convergenceTable 12. FEA Set-up of Wheel in Pro/Mechanica.

In order to set up the torque onto the wheel, it was necessary to use a weighted link. This is

because the torque is distributed all across the wheel, thus necessitating the use of a

weighted link. To do this, a torque was placed on a point and then it was connected to the

wheels edgeusing a weighted link. This properly distributed the torque throughout the

entire wheel.


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analysis was set up using 9 passes with 1% convergence. The results of the analysis are

shown below.

The following figures show the analysis results. As shown in the figure below, the

maximum von Mises stress occurs at the wheels connections to the center. The VMS has amaximum of 6.617 MPa. Given Aluminum 6061syield strength of 206 MPa, the piston has

a safety factor of 31.1.

Figure 33. Fringe Plot of the WheelsVon Mises Stress.


versus pass is shown below. This analysis converged very easily, considering that the graphplateaued from pass 4 to pass 8.

Figure 34. VMS Convergence of Crankshafts FEA.


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Also shown below is the fringe plot of the displacement of the wheel. This fringe plot shows

the complete deformation of the wheel as it undergoes a distributed torque. As expected,

the wheel undergoes maximum displacement on the entire round.

Figure 35. Fringe Plot of the WheelsDisplacement.


Measure Value



Safety Factor 31.1

Maximum Displacement 0.003453 mmTable 13. FEA Results of Wheel in Pro/Mechanica.


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Optimization

Optimization was performed in Pro/Engineer on the piston. The piston was chosen because

of the simplicity of the force and its location relative to the can. The design optimization

chosen was to hollow out the center. In Pro/Mechanica, the set-up is the same as it was in

FEA with one exception, which is that a half-model was used. This changed the constraintsto symmetry constraints and changed the force to half magnitude. The AutoGEM controls

were maintained from the FEA. The set-up is shown in the figure below.

Figure 36. Optimization Set-up of Piston.


Force 225N on piston top

Constraints Fully constrained at circular edges

Material ABS Plastic

Pro/Mechanica

Techniques used Volume Regions (3)

AutoGEM controls (2)

- Edge distribution, 30 nodes- Edge exclusion

Symmetry half-modelAnalysis 1.Static Analysis using 9 passes at 1%

convergence

2.OptimizationTable 14. Optimization of Piston in Pro/Mechanica.

Once the piston was set-up, a static analysis was run using multiple passes at 1%

convergence. The results of this analysis run were used in the optimization run. The


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optimization parameters was performed to ensure a safety factor of above 2.5. This meant

that the lowest VMS allowed is 14.0 MPa, with the hollow cuts dimensions as the limiting

factors. The optimization parameters are summed up in the table below.


Safety Factor Limited to 2.5 at the lowestvon Mises Stress 14 MPa

Material ABS Plastic, Yield Strength of 36MPa

Limiting Dimensions Height and width of hollow cutTable 15. Optimization Parameters of Piston in Pro/Mechanica.

The optimization analysis ended up hitting the limits upon its completion. The optimized

model is shown below, with the optimized hollow cut at the largest size.

Figure 37. Optimized Piston.

To ensure the optimization was done correctly, FEA was performed on it. The results are

shown below.


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Figure 38. von Mises Stress of Optimized Piston.

As can be seen in Figure 38, the maximum VMS now occurs at the connection of the hollow

cut at a magnitude of 7.981 MPa. This results in a safety factor of 4.5, which is still above

the optimization requirements. This means that the hollow cut does not create adverse

effects on the piston.

This picture shows the displacement of the optimized model and verifies that the

displacement is still under 1.0mm. This further ensures that the piston is designed

properly, even with the optimized design and the hollow cut.


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Conclusion

The can crusher is based on a car engines designand uses the standard piston design as

the basis of a crank-slider. The can crusher has six chambers for a total can capacity of six

cans. It is a practical design that takes into account both human factors and engineering

reliability. For example, the can crusher was designed to crush six cans in one process, andwith the proper mechanical advantage so as to maintain a comfortable amount of effort.

Additionally, as it was designed, the can crushers lowest factor of safety is 8.08 before

optimization. This safety factor is attributed to the piston, which is made of ABS plastic. All

other parts are made of Aluminum 6061 and have safety factors above that.

As such, this can crusher is a practical long-lasting alternative to the can crushers currently

on the market. It is a novelty item for people who appreciate cars and it does not sacrifice

anything in its design. If this can crusher were to be manufactured, there may be a few

designs that can change during the iteration process, but theoretically, this can crusher is a

great design as is.


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Appendix

2D Drawings

Figure 39. 2D Drawing of Casing.


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Figure 40. 2D Drawing of Piston.


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Figure 41. 2D Drawing of Connecting Rod, Top.


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Figure 42. 2D Drawing of Connecting Rod, Bottom.


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Figure 43. 2D Drawing of Crankshaft.


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Figure 44. 2D Drawing of Gear.


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Figure 45. 2D Drawing of Wheel.


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Exploded Views

Figure 46. Exploded View of Assembly.


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Figure 47. Exploded View of Connecting Rod

crusher simple machine

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