Group 3 - Kawasaki Compressor - Gate 3
Main Page: http://gicl.cs.drexel.edu/wiki/Group_3_-_Kawasaki_Compressor_1
Gate 1: http://gicl.cs.drexel.edu/wiki/Group_3_-_Kawasaki_Compressor_-_Gate_1
Gate 2: http://gicl.cs.drexel.edu/wiki/Group_3_-_Kawasaki_Compressor_-_Gate_2
Gate 4: http://gicl.cs.drexel.edu/wiki/Group_3_-_Kawasaki_Compressor_-_Gate_4
Gate 5: http://gicl.cs.drexel.edu/wiki/Group_3_-_Kawasaki_Compressor_-_Gate_5
Project Management: Coordination Review
This far into the project, we should be working fairly well together as a group. Although we are completing the required material and are knowledgeable on the subjects within the project, we do seem to be having a difficulty with conflicting schedules. As stated in previous gates, all of the group members are taking full and intensive course loads. These courses have recently put a slight damper on group meetings and productivity due to weeks filled with heavy tests and time consuming work.
Another issue is that certain members are not receiving texts which are sent to all members of the group, which unfortunately ended up with the group missing out on a day of meeting and foreseen work.
We plan to overcome these set-backs by attempting to plan ahead not only in our own schedules, but in the groups schedule as a whole. On the Friday of each week, after our MAE 277 class (which all members attend) we will meet briefly and discuss all plans for each member over the next week, as well as determine what needs to be completed during that week in order to stay on schedule with our proposed Gaant chart from Gate 1. As for our previous contact plan not being feasible due to texts not being received, we have decided to format a new one. If a response has not been received from a member within a half hour, a second text possibly from another group member will go out to that member. If no response is received within the next 15 minutes, a call to that member will be made and a voice-mail will be left if the member does not pick up. At that point, it is obvious that the member was attempted to be reached in all ways possible, and responsibility is on the member to check their messages. We don't predict an issue, but if one does happen to occur, the teacher will be notified.
As far as previous challenges, our biggest issue was getting things done early and taking the time to work smoothly and patiently. Recently, we have been starting our projects earlier and setting aside enough time to produce a quality product. All group members are contributing and we've done a pretty good job of accessing their strengths and utilizing them to full potential.
Product Archaeology: Product Evaluation
The product archaeology contains a Component Summary and a Table of Component Fasteners in the manufacturing and assembly of the Kawasaki Air Compressor. Also included is a Component Analysis of the most integral components which make up the important processes and functions throughout the compressor.
Below is a list of components including a picture of each component and a brief explanation of the manufacturing process used, number of components used, any observations we had on that component.
|Component Name||Image of Component||Quantity Used||Component Function||Manufacturing Process||Observations|
|Quick Coupler Air Hose||1||This component provides a nozzle for air to be sprayed at high speeds and is meant to connect/disconnect quickly.||The quick coupler air hose was manufactured by extruding pvc into a tube shape and allowing it to cool in a coiled position.||Only written English was used for the specifications.|
|Handle||1||This component makes the compressor portable. By lifting on the handle, one side of the compressor will lift up and it will be possible to roll it on its wheels.||The handle is made of steel, which was extruded to form a seamless tube. This was then bent into the required shape.||The handle has been painted to be more aesthetically pleasing. It also was observed that there was no weld or seam on the steel tube that it is made up of.|
|Motor Shroud||1||This component's function is to protect the consumer from hot parts and the spinning fan. There is also some aesthetic appeal to having the inner components covered.||The motor shroud was manufactured through injection molding to form its shape.||An aesthetic surface finish has been applied. Parting lines can be seen on the inside of the motor shroud.|
|Air Filter||1||This component is to filter out any harmful particles and provides clean, debris-free air into the compressor assembly and tank.||The ends of the filter were injection molded, and a paper air filter was glued to each of these ends.||The adhesive did not strongly bond the paper air filter to the rubber parts. The air filter was also quite thin.|
|Air Filter Housing||1||This component is meant to hold the air filter in place and to transfer clean air into the piston-cylinder assembly.||The housing has been drawn or die cast from thin steel.||NA|
|Fill Line||1||This component's function is to transfer the exhaust air from the piston-cylinder assembly to the tank.||The fill line was drawn from copper, and has steel cooling surfaces wrapped on.||The steel has a ruffled edge that uses friction to keep it in place on the fill line.|
|Pressure Switch||1||This component's function is to turn the compressor on/off based on either manual user input or maximum pressure in the tank.||This was not intended to be taken apart, but the outside case was injected molded and is made of plastic.||NA|
|Bleeder Valve||1||This component's function is to bleed pressure from the tank manually.||The bleeder valve was manufactured from brass, it was machined and then assembled. A wing nut is used to open and close the bleeder valve.||NA|
|Rubber Feet||2||This component's function is to stabilize the compressor when sitting on the ground. The rubber feet will prevent the compressor from rolling.||The rubber feet were formed using injection molding.||NA|
|Wheels||2||This component's function is to roll when the front end of the compressor is lifted. The wheels add mobility to the compressor.||The plastic wheels were formed by injection molding.||NA|
|Intake Manifold/ Cylinder Head||1||This component's function is to intake air from the air filter and provide it to the piston assembly upon expansion. It also provides the exhaust line (fill line) air under compressor.||The cylinder head was formed by die casting aluminum to form the shape. The part was then milled to fit flush with the valve plate, a hole was drilled and tapped in order to connect to the fill line.||The surface finish is rough, and machine marks can be seen in the holes drilled for the bolts, and on the bottom surface.|
|Cylinder Head Gasket||1||This component's function is to provide a secure and proper seal between the crank case and the cylinder.||The gasket was pressed and cut from a paper like material.||The gasket can be seen in the photo, it seals between the crank case and the cylinder.|
|Capacitor||1||This component's function is to provide a consistent amount of power to the electric motor and electrical components.||The capacitor was drawn into its shape and manufactured out of aluminum.||The Capacitor has two tabs on the bottom that connect electrically to the air compressor. It also has a threaded extension that allows it to screw into the crank case.|
|Plastic Guard||1||This component's function is to protect the capacitor.||The plastic Guard for the capacitor was formed by injection molding.||Riser marks can be seen on the top of the component. No surface finish operations have been performed, riser marks and uneven edges are present on the part.|
|Circuit Breaker||1||This component's function is to protect important electric and mechanical components in the event of failure.||The circuit breaker was not disassembled, the case of it was injected molded plastic, with turned brass connections.||NA|
|Oil Fill Plug||1||This component's function is to provide an area to input oil as well as plug that area during normal use.||The oil drain plug is made of plastic and has been injection molded||A visible parting line can be seen on each side of the oil fill plug.|
|Valve Plate||1||This component's function is to restrict air from being released during expansion, and to allow a place for air to be released into the exhaust line during compression.||The valve plate is machined out of aluminum, with a steel resistor plate bolted above it.||The plate has a machined surface finish on the top surface and has a gasket glued to the bottom of it.|
|Cylinder||1||This component's function is to house the piston and provide an area to create compression.||The cylinder is made out of iron and has been sand casted.||The external surface finish is extremely rough, while the bore of the cylinder has been finely machined and finished. Four holes have also been machined so bolts may pass through the cooling surfaces.|
|Expansion Ring (Piston)||1||This component's function is to hold the wrist pin in place.||This component was extruded into a wire, and then bent into its shape||NA|
|Piston||1||This component's function is to create the suction of air under expansion within the cylinder and to compress the air out of the piston-cylinder assembly into the exhaust line when in compression.||The piston was cast from aluminum, and then machined into its final shape.||A parting line could be seen inside the bottom of the piston, not visible on the outside. The outside has been finely machined to be as close to possible to the designed dimensions. The piston was also turned to allow piston rings to be added.|
|Piston Rings||1||This component's function is to protect important electric and mechanical components in the event of failure.||The piston rings are made from steel and rolled into shape.||These pins are flexible, provides a tight fit between the piston and the cylinder|
|Wrist Pin||1||This component's function is to connect the piston to the rod.||The wrist pin is made of steel and was rolled in order to obtain its shape.||The pin has a high surface finish.|
|Crank Case Cover||1||This component's function is to provide access to the crank, shaft, and rod within the piston-cylinder assembly.||The crank case cover was die cast from aluminum, and machined in order to fit flush against the crank case and the gasket. Holes have been drilled in order to allow bolts to pass through the cover and attach it to the crank case.||The cover has a rough surface finish, and has a few areas that have been machined.|
|Crank Case Gasket||1||This component's function is to provide a solid seal so that no oil escapes the crank case through the crank case cover.||The gasket for the crank case was constructed by injection molding.||The gasket had a rubber texture to it and was not highly rigid.|
|Connecting Rod||1||This component's function is provide a connection between the crankshaft and the piston.||The Connecting Rod was formed into its shape by die casting||The Connecting rod is made of light weight aluminum, parting lines could be seen along its sides from when it was cast.|
|Oil Drain Plug||1||This component's function is to provide an area to drain the oil from the crankcase during an oil change.||The oil drain plug was rolled into its shape and machined to give it a hex head.||NA|
|Electric Motor Cooling Fan||1||This component's function is to draw hot air from the compressor and electric motor.||The electric motor cooling fan is made of aluminum and was die cast. It has been machined to allow a set screw to lock the fan to the shaft of the motor.||The fan has a rough surface finish, it is not visibly exposed to the user, so any aesthetic flaws would not be visible. It also has a hole from when it was cast. The hole is flat and allows the fan to stay in place on the motor shaft.|
|Electric Motor||1||This component's function is to spin the shaft which turns the crank in the piston-cylinder assembly.||The copper wiring was drawn and and then coiled to achieve its shape. The iron casing was cast and then machined to achieve its desired shape.||There were visible machining marks on the iron casing. There was also some plastic line that helped to hold the copper wiring in place.|
|Pressure Safety Release Valve||1||This component's function is to release air in the event the tank does not shut off at its programmed maximum pressure.||The pressure release valve is made of brass, it was turned and machined to have threads.||It has a spring attached to keep the valve closed.|
|Air Line||1||This component's function is to provide air from the tank to the pressure switch and quick-connect tool connection fitting.||The air line is made of copper and has been extruded into its tube shape. It was then bent, and brass fittings added to the ends.||This component consists of two different materials, and one end of the air line is flanged.|
|Pressure Gauges||2||This component's function is to provide accurate measurement of the pressure of the air within the tank.||These are made from 2 plastic cases which were injection molded. Two screws hold the gauges together, and they have a brass fitting that connects them to the air compressor.||NA|
|Tank||1||This component's function is to hold pressurized air for use with air-powered tools.||The tank is made from steel, was bent into its shape, and had the ends welded on. The tank was painted green afterward.||The welds are clearly visible on the ends of the tank.|
List of Component Fasteners
Below is a list of fasteners used to assemble components within the Kawasaki Air Compressor. We have included the fastener type, size, and quantity used.
|Fastener Type||Size||Quantity Used|
|Head Bolt||M8 x 1.25 x 100 SHCS||4|
|Screw||M4 x 0.7 x 10||4|
|Screw||M6 x 1 x 16||2|
The following will be a complete in depth description of the of the different essential components in the air compressor. We will be examining the engineering decisions during design, such as component functions, component geometry, material, and appearance, manufacturing methods and component complexity.
Scale of complexity
Each analyzed component was evaluated on its complexity for manufacturing and how complex the component's interactions are.
Manufacturing complexity: The manufacturing complexity is based on a scale consisting of a point system. the points are awarded for features of the parts that would add to its complexity. below is a list used to award points
- 1 point for each hole drilled
- 1 point per tapped hole
- 1-3 for amount of machining. a 1 is used if only minor machining is used, and a 3 is defined as the whole part being mostly machined after it is formed.
- 1 point for each slot/ o-ring groove
- 1 point for each pice that is press fit
- 1 point added for additional materials used
- 1 point if the part has a higher surface finish applied
- 1 point if the part is cast, and side actions are needed.
- 1 point awarded if the holes are broached
- 1 point if the part is painted or anodized.
- 1 point added for each piece or section welded.
Interactions complexity: The complexity of the interactions are based 0on frequency of use and connections to other components. This uses a similar point system as above, below is list of how points are distributed.
- 1-3 points for how often the part is used during the operation of the product.
- 1: rarely used. 2: frequently used. 3: constantly used.
- 1 point for each component the part couples with.
- 1 point for every additional function the part carries
The piston serves as the force needed to compress the air into the tank. It's function is to apply pressure to a volume of air and push that volume into the tank where it is stored.
- Taking air into the cylinder and then pushing that air into the tank for later use is the pistons only function.
- There are 2 different flows associated with the piston. Material and energy are both flows in which the piston deals with. Material in the form of air and energy in the form of pneumatic potential are both transferred from the piston's chamber into the tank by the pressure from the piston itself.
The motion of the piston causes it to heat up during pressurizing. It functions better when it is at room temperature, which the cooling fan helps with. No other environment restrictions affect the piston.
Component Form (Geometry, Material, and Appearance)
The general shape of the piston is cylindrical.
- The piston is axis-symmetric and contains two holes for the wrist pin to slide through. It also has three indented grooves near the top in which the piston rings fit, which prevent oil from entering into the cylinder.
- It is primarily 3-dimensional, with a length, height, and depth.
- The piston is has a diameter of 1.887 inches and a height of 1.49 inches.
The piston is cylindrical because it needs to fit inside the cylinder and slide up and down smoothly. If a piston was designed to be square or rectangular, not only would the cylinder have to be shaped to fit it, but there would be a high friction coefficient in the corners and likely a good amount of scoring of the cylinder walls during use. A cylindrical shape is the best for a piston because it will create the smoothest complete mating surface between itself and the cylinder wall.
The piston weighs roughly 9.7 grams.
The piston is made of cast aluminum.
- Manufacturing decisions likely did not impact the material selection for the piston. Besides the fact that aluminum can be machined fairly easily, other factors such as the physical responsibilities and movements took more precedence in deciding the material.
- Aluminum is a good material to use for a piston because it is lightweight, which means that during each change of direction the piston will put a lesser force on its connected components. This also means that the motor will not have to work as hard to rotate the piston assembly.
- One of the Global factors influencing this decision are that aluminum is widely available. Another factor is that this component is not exposed to any external elements besides the air which moves through the filter into the cylinder. Even with the passing air, aluminum would be a good choice of material due to good resistance to corrosion versus other metals such as steel which have high corrosion factors
- Economic factors which influence this component are those such that aluminum is widely available and fairly inexpensive. It also has a decent life length before breaking down and corroding, which provides a longer life of the compressor and less maintenance cost for the owner.
- Environmental factors were likely not heavily considered in the deciding aluminum to be a material due to the fact that aluminum is not a heavy metal and that there is no intended disposal of the component after a specific amount of time.
- Societal factors were likely also not heavily weighted due to the fact that consumers should not be in direct contact with the piston.
The aesthetic properties of the component are smooth and shiny due to being heavily machined.
- These properties have a large purpose. Since the piston runs directly against the sides of the cylinder, it needs to have a smooth surface on its sides.
- The component is a shiny silver color, likely caused by the machining during the manufacturing process.
- The surface finish of the piston is smooth. This is so there is a small friction coefficient between the piston and cylinder.
The finish is purely for functional purposes and not for aesthetics. The piston is not intended to be seen by the consumer therefore its aesthetics have no value. Although the functionality of having a smooth finish on the piston reduce the force needed for the motor to turn it as well as lessen the coefficient of friction between itself and the cylinder wall.
The piston was first cast and then machined for smoothness.
- Casting is evident due to parting lines on the inner edges of the piston. These parting lines are clear indications of an initial process of casting to create the overall shape of the piston. The piston was then turned and machined on a lathe to create a smooth top and sides. This is evident due to the shininess and smoothness of the sides of the piston as well and the turning marks on the top and sides. These characteristics could only be achieved through machining.
- Material choice likely did not impact the manufacturing process. If the manufacturers decided to use a different material, it would need to be manufactured the same way. First through casting, and then machined for fine tuning and to create smooth surfaces.
- The shape did likely impact the method of manufacturing. The original shape would be very difficult to machine completely or to cast completely without obtaining rough edges. Therefore, a cast was initially used to get the most accurate shape possible and afterward machining could be used to obtain the desired external characteristics.
- Global factors taken into consideration may have been that aluminum casting is available everywhere, not limited to one area.
- Societal factors were most likely not taken into account for the decision to cast the aluminum.
- Economic factors were very important in the decision to cast the part due to the fact that casting is faster and cheaper then using machining techniques alone to create the aluminum part. A combination of casting and machining was used to achieve the best economic outcome for manufacturing.
- Environmental factors taken into account are the ability to make the part a significant number of times without wasting any resources.
Manufacturing complexity : The component is highly machined on almost all of its surfaces. 2 slots have been accurately turned to allow piston rings to be fitted around the piston. The wrist pin holes have been machined as well, along with a slot for the expansion ring. Due to these factors, this component gets a rating of 7 for the manufacturing complexity.
Interaction complexity: The component interacts with the wrist pin, piston rings and the cylinder. this part is used every time the compressor is turned on. These factors give this component a 7 for an interaction rating. 3 for frequency, 1 for each ring, 1 for the connecting rod and another point for the cylinder.
The crank case is an integral part of the compressor and serves many functions.
- This contains oil to lubricate and cool the piston,connecting rod and crank shaft
- This serves as a point to mount the electric motor to
- The crank case serves as a guide for the shaft to connect to the connecting rod
- The circuit breaker is mounted securely
- The crank case mounts to the tank, and allows the cylinder to mount to it, which aligns the piston vertically. The crank case allows many components to be mounted in one stable position.
This component of the air compressor operates in a wide variety of environments. since the air compressor may be used indoors or outdoors. inside the crank case may warmer from the friction of the piston and cylinder.
Component Form (Geometry, Material, and Appearance)
The general shape of the component, is a hollow rectangular cube. it has an open face on one side.
- It is symmetrical about the line going through the crank shaft, with the exception of the oil drain plug.
- The crank case has 3 dimensions, and many complicated reinforcements and extensions on its shape.
- the component is approximately 8.5" x 7" x 5.5"
The shape of the crank case helps to hold all the components of the air compressor together, and to align them properly. it also allows service to be done, mainly to change oil and remove the crank shaft and piston assembly. it also helps to mount every component to the tank.
The crank case weighs roughly 1.5 lb
The crank case is made of aluminum that has been cast.
- aluminum was chosen most likely because of its cost and ease of manipulating.
- The material chosen for this component needs to be machined, or cast easily and needs to be strong enough to not deflect from the torque of the motor or other forces generated in the piston cylinder assembly.
- Global factors Were most likely taken into consideration , aluminum is a common metal for manufacturing around the world, in which almost everyone works with.
- Societal factors were taken into consideration when building the component, they include portability. aluminum is light weight, and because this is a portable air compressor society looks for how portable the overall product is. aluminum is a better choice than cast iron or steel because it cuts down on the weight dramatically.
- Economic factors also influenced The choice to manufacture the crank case from aluminum. aluminum is generally cheaper than other metal alloys and cheaper to machine and cast.
- Environmental factors may have been taken into consideration, besides the benefits of cost and weight aluminum is very easy to recycle and is widely recycled around the world, although the manufacturer might not intend for their product to be rebuilt into something else, they chose a material that is highly recyclable .
The component is also designed to have aesthetics attractive to contractors and other individuals who would use the product. mainly the rigid look of the crank case.
- The component has a slight aesthetic purpose. it may be meant to look rigid and uniform which makes
- The component is silver in color, the same color as the material it is made up of.
- The component has not had any surface finish improvements performed on it, it still has a rough finish from when it was cast. This surface finish doesn't appear to improve its function
The crank case was cast out of aluminum.
- There are parting lines along the top of the crank case and along the side of the motor. this shows that a side action may have been performed during the process.
- since aluminum was used, casting was most likely chosen because of its ease to cast into the shape of the crank case.
- The shape of the product only affect the amount of side actions needed to make the part.
Global factors taken into consideration, may have been that aluminum casting is available everywhere, not limited to one area.
Societal factors most likely were not taken into account for the decision to cast the aluminum.
Economic factors were very important in the decision to cast the part. casting is faster and cheaper than machining the aluminum part.
Environmental factors taken into account are the ability to make the part a large number of times without wasting any resources
Manufacturing complexity: This component has been die cast from aluminum, it appears to have multiple parting lines, implying the use of side actions. some additional milling has been done as well. There is a total of 13 holes drilled, and 4 of them have been tapped. The surface that mates with the cylinder has been machined to a high surface finish as well. These factors give this part a rating of 21. It also has been machined to allow the crank to pass through, with a bearing press fit into place. This number is high because of all the drilled holes and the side actions needed.
Interactions complexity: This component interacts with many pieces of the compressor. and attaches to most of them, and is also needed every time the compressor is run. It connects to the motor, tank, cylinder, cirbuit breaker and capacitor. These factors give it a rating of 8 for interaction complexity.
The primary function of the electric motor is to convert electrical energy from the power source into a magnetic field which transfers energy into the shaft through several different processes:
- Electric current is first sent into the copper wire that coils around the motor hundreds of times to form a tightly packed spiral of copper wire.
- That electric current flows through the wire which creates a strong magnetic field inside of the coils.
- The current then switches after the shaft has completed one half turn as to switch the orientation of the magnetic field and make the shaft continue to spin in one constant direction.
- The flows associated with the electric motor include the electrical energy in the form of current flowing into the component with the out flow being the magnetic field which the electric current creates.
The electric motor can perform in a variety of environments including indoor, outdoor, high temperature climates and low temperature climates. The only real restriction to using the electric motor is that it must be used in a dry place. It cannot be used in a rain or snow because the water could potentially short out the motor which could harm both the motor as well as the user.
Component Form (Geometry, Material, and Appearance)
The electric motor is essentially a large cylinder which is made up of a tightly wound spiral of copper wire and a cylindrical cast iron housing which holds the wires in place.
- The motor has an axis of symmetry running through the center of the motor. The coils and the cast iron housing is rotated about this center of axis.
- It is primarily two dimensional including a radius and a length which runs along the primary axis.
- The radius of the electric motor was about 2.5 inches and the length was 6 inches.
- The electrical coils and the cast iron housing weighed approximately 16 pounds.
The shape of the motor is essential to its function. The magnetic field is created by the copper wiring that is spiraled around the center axis. If the wires were not in this cylindrical form, then the current would not be able to produce a uniform magnetic field and the electrical energy would not be able to transfer over to rotational energy efficiently.
The electric coils of the motor are made of copper which are wound in a way to maintain their shape without much other forces. The housing which holds the wires in place is made of cast iron. The iron core is used to enhance the electric magnetic field on the inside of the coil area.
- Manufacturing decisions did not impact the decision to use copper wire in this component as much. Copper wire is the most efficient and widely used material to transfer current so manufacturing decisions would not impact the decision to use copper. It is also very essential to the function of the compressor because of its ability to transfer current so efficiently because it has such a small resistance. There is no other metal wire that transfers current as efficiently and at the same cost as copper wire.
- Some design factors that went into deciding to use copper wire include the the fact that copper is a universal material that can be mined from different regions all around the world. It has been utilized by many cultures before it was even used as an electrical wiring. Copper is also a very cheap, durable material which is widely available so it is very economical to use it. Drawing the copper into its wire form is a fairly clean method, so the environment will not be negatively effected by using it. Copper is such a commonly used product as well for electrical wiring, so it does not effect the way the user will feel about using the component.
- Cast iron was used because its ease to cast, its ferremagnetic properties, and because it is a readily available heavy metal. It helps the product function because it helps cancel out any magnetic field that would exist outside of the coils which could potentially harm the product or make it not work as well. It also provides a way to enhance the magnetic field on the inside. Since the magnetic field is going to be much weaker outside of the coils, it is going to be easy to cancel out the field using the iron casing.
- Some design factors that went into using iron as the motor casing include the fact that iron is a very commonly used material around the world and can be easily mined from many different regions. Iron has had different functions with all sorts of cultures throughout the world, so it can be said that the influence to use iron for the casing came from those regions. Since iron is such a readily available material as well, it is relatively cheap compared to other materials which may be used. It is also very durable to so it will last long and will not effect the performance of the compressor.
There are not many aesthetic considerations concerning this component. It is not easily seen because it is covered by other components as well as the plastic cover, so there is really no aesthetic purpose to the component. Each material included in the component is the color that it was originally created in, so there were no alterations made there because it is not readily visible. The copper wire is very smooth because that is how it was manufactured. The iron casing has a rougher surface finish, but it is still fairly smooth because it was machined to form the cylindrical shape. The surface finish though does not really effect the performance of the motor.
There were a variety of manufacturing methods that were used in making this component. These methods include drawing out the copper into copper wiring. The iron casing was cast and then machined to achieve its shape.
- The wires were obviously drawn because that is the most effective and widely used method to make copper wiring.
- Copper is also a fairly soft material so it is easy to draw out and make into wires.
- The iron casing was cast and then machined because there are visible lines on the casing which would suggest that a machine worked on it to cut it into the desired shape.
- The shape was fairly important for the casing which is why it had to be machined after it was cast. In order to form the smooth, cylindrical shape, it had to be more than just cast.
There are several design factors that could have gone into deciding how the motor was manufactured. Some global considerations include that all of these drawing and casting are methods that have been used for years all over the world to create many different shapes and sizes.
Economically, drawing and casting are both fairly cheap methods of manufacturing. Machining is more expensive, but it was necessary in order to make the shape of the iron casing.
Manufacturing these do not really effect the environment negatively.
There were not really any social factors that went into manufacturing this component.
Manufacturing complexity:The electric motor consists of tightly wound wire contained in an iron core that wraps around the stator. because this was not manufactured with any of the other parts, its hard to rate its manufacturing complexity. The wire is wrapped precisely, the stator is highly balanced in order to prevent failure, and the iron core around the wires is uniform to create a uniform electric field. our scale does not take this into account, in order to do it accurately, it would need to be changed to accondate this; perhaps be biased in order to give it what seems to be enough points.
Interaction Complexity: This component interacts with the electrical wires is also used whenever the compressor runs, is also connected to the crank shaft, and the cooling fan. according to our scale, this gives it a rating of 6.
The cylinder performs a couple of functions in the air compressor
- The cylinder guides the piston up and down
- The cylinder also provides a rigid seal/ environment where air can me compressed and transported to the tank for storage.
- It also serves as a rigid location to mount the valve plate on.
- The flows associated with the cylinder are a material flow of air, and the mechanical energy flow of the piston moving linearly in the cylinder.
The cylinder operates in an indoor and outdoor environment, and in contact with high temperature from the friction of the piston sliding along the cylinder.
Component Form (Geometry, Material, and Appearance)
The cylinder is shaped similar to a rectangular cube, with a cylindrical hole drilled through its length.
- The cylinder is symmetrical through its length horizontally and vertically.
- the component is 3 dimensions, it has a length width and height.
- The cylinder is approximately 4.5" x 3.5" x 2.5" with a 2" diameter bored hole
The inside of the cylinder needs to be symmetrically and completely uniform in order to create a good seal between the cylinder and the piston. A cylindrical shape also has the smallest surface area which allows the least amount of friction between it and the piston.
The cylinder weighs approximately 2 lbs
The cylinder is cast from iron
- A quick , cost effective, strong and easy to manipulate material is needed, iron would be suitable for all these constraints.
- The material needed for the cylinder needs to be extremely rigid and capable of obtaining an extremely fine surface finish.
- Since only a simple shape is needed in order to obtain the cooling surfaces, casting and machining were the most appropriate methods
Sand casting was most likely used to make the cylinder.
- There are visible parting lines on the top and sides of the cylinder.
- Because iron was used for this part, casting was chosen as a preferred method.
- since the cylinder is a basic shape, and symmetric, casting could be used to create the shape.
Global factors taken into consideration for deciding to cast the iron are that iron has been cast everywhere geographically, and is an extremely common process.
Societal factors taken into consideration may have been how cylinders are cast in the immediate area.
Economic Factors taken into consideration are the cost to make this part, and the time needed. sand casting iron into the cylinder was a cost effective way to shape the cylinder head.
Environmental Factors that were taken into consideration during the manufacture of this part included the re-usability of the sand to cast more cylinders.
Manufacturing Complexity: This component was sand cast, with no side actions needed. the only machining done was boring out the cylinder, which needs a high level of machining. 4 holes are also drilled to allow bolts to pass through. Due to these factors, our rating system gives this part a rating of 5.
Interaction complexity: This part interacts with the piston, piston rings, crank case and cylinder head. it is used every time the compressor is run, giving it a rating of 7.
This component has only one function. That function is to hold the piston and crank rod together so they move in one motion.
- There aren't any flows associated. It only purpose is to hold other components together.
- This should work in all environments. The piston can't be to heavy or else the rod will shear.
Component Form (Geometry, Material, and Appearance)
The connecting rod is shaped kind of like a bar with two different size holes one at each end.
- The rod is symmetrical through its length vertically and both centers of the holes match up to this line of symmetry as well.
- The component is 3 dimensions, it has a length width and height.
- The rod is approximately 4.5" x 2.5" x 5" with a 1" and .5" diameter hole
The inside of the cylinder needs to be symmetrically and completely uniform in order to create a good seal between the cylinder and the piston.
The rod weighs approximately 2.3 grams.
The connecting rod is molded with aluminum
- A quick , cost effective, strong and easy to manipulate material is needed, aluminum would be suitable for all these constraints because it is easy to manipulate compared to steel or iron.
- The material needed for the rod needs to be extremely rigid and capable of supporting the force of the piston's movement at higher temperatures.
- Since only a simple shape is needed in order to obtain the geometry of the rod, molding was the easiest way to accomplish this.
The manufacturing process to make this is was molding. The hollowed mold of the component's shape was filled with aluminum and cooled down to create the shape it has. The evidence given is the visible parting line made from the 2 molds. The molds are cut down the middle in half so when they are used, the final product will have parting lines. The small pin was drawn and then welded to the tip of the connecting rod as well.
- Aluminum is cheap and easily manipulated so that would effect why the material as chosen over another metal.
- Although aluminum is cheap it has a lower strength as well. However this isn't a problem since the amount of stress the component takes is minimal to the yield strength of aluminum.
Manufacturing complexity: This part was most likely die cast, with minimila machining done to bore out where the connecting rod meets the wrist pin, and crank shaft. This gives the connecting rod a 2 on our rating of complexity.
Interaction complexity: This part is used every time the compressor runs, and interacts with the wrist pin and crank shaft. giving it a rating of 5 according to our scale.
This component of the Kawasaki Air Compressor is used to allow the operator to lift one end of the compressor easily and move it by rolling it across the ground.
- The handle is only used to move the compressor by either rolling it or picking it up.
- The flows associated with the component are strictly signal flow. The operator is the only one that can physically apply the force needed to mobilize the air compressor.
The Component is designed to be used indoors, or outdoors and to withstand the force put on it when moving the air compressor.
Component Form (Geometry, Material, and Appearance)
The general shape of the component, is a narrow, cylindrical tube bent in four different places.
- The Handle is symmetrical in length and the diameter of the piping used.
- The Handle has primarily 2 dimensions, a length and a width, and a diameter.
- The component is approximately 21 inches long, 7.5 inches wide, and a diameter of .75 inches.
The shape of the handle allows the user to hold it while standing, because it is bent, it is placed on a lower spot of the compressor, and it extends upwards towards the user around mid-thigh height.
The handle weighs roughly 1.5 lb.
The component is made of Steel tubing.
- Because of its standard availability, and ability to bend it into different shapes, steel tubing was used.
- The material needed to withstand deflection and shearing associated with the weight of the compressor. It also needs to be light weight since the compressor is portable. Steel has a high enough Young's Modulus.
- Global factors include the length of the handle and it's position relative to an average person. The average human being can reach it and lift it up off the ground enough to wheel it around.
- Societal factors were taken into consideration when building the product. It is designed to be portable, and to be used by someone who is working with power tools and possibly heavy materials.
- Economic factors also influenced The choice to manufacture the handle from hollow steel tubing. Hollow tubing is cheaper and is strong enough to move the compressor instead of solid steel tubing which would cost more and be a waste of material.
- Environmental factors were most likely not taken into consideration. Steel can be melted and formed back into another shape, but the manufacture did not build the component for it to be turned into another product.
The component is also designed to have aesthetics attractive to contractors and other individuals who would use the product.
- The bar is symmetrical and neatly bent.
- The component is green in color, to match the tank, and because green is the color associated with Kawasaki.
- The component may have been given a fine surface finish, It has also been painted Green. This surface finish makes the product more attractive to the operator. The high surface finish was made for both aesthetics and function. The handle needs to be smooth in order for the operator to grab a hold of it and apply a force.
- The Handle sticks out significantly allowing the user to identify it as something to grasp.
The handle was made using the process of extrusion, and painted for a finished surface.
- The constant cross sectional area is evidence that supports the the use of the extrusion process.
- Shape influenced this manufacturing decision. This is the simplest, quickest, and most standard and way of manufacturing this type of material into this shape.
- Material choice was likely not a contributing factor in the choice of manufacturing processes since extrusion is the best way to form a shape such as this with most metals.
- The Global factor taken into consideration during the manufacturing of the product is the availability of of steel. Steel tubing can be made around the world, and is commonly used everywhere.
- The Societal factor taken into consideration is the strength of the material. Since this component will be used to lift part of the compressor and allow it to be mobile, it must be strong enough to hold the weight securely and not bend under stress.
- The Economic factors taken into consideration are the length of time needed to manufacture it into a tube. Also the cost of mass production with an assembly line.
- The Environmental factors taken into consideration during manufacturing seem to be less relevant. The steel tubing does not create any pollutants, and is not a heavy metal that is harmful to humans or animals.
Manufacturing complexity: This component is extruded into a tube, bent into shape and painted. It gets a rating of 2 for manufacturing complexity.
Interaction complexity: This component only interacts with the tank, and is used occasionally to move the compressor. this gives it a rating of 2.
The Tank has multiple functions.
- It's two main functions, are to hold the pressurized air for later usage, and to act as a base for other components to be assembled to.
The flows associated with the tank are energy, and material flow.
- The energy flow is internal and pneumatic and the material flow is air. As the air fills the tank, more and more air is pushed into the tank until it reaches a certain pressure. This increases it's internal energy as well.
- The tank can perform both functions in any environment. Typically, the tank should be at room temperature to help stabilize the pressure and volume inside.
Component Form (Geometry, Material, and Appearance)
The general shape of the tank is a cylinder. The flat ends have been inflated to create a semi-sphere to increase volume. The tank and the ends having a cylindrical shape provides the lowest surface area to volume ratio.
- The tank looks like an elongated bubble. This effect increases the original volume of the tank without changing the dimensions.
- Since the tanks main function is to store volume, the tank itself must have three dimensions
- The tank itself is 25 inches long with a diameter of 10.5 inches.
- It weighs roughly 30 pounds.
The shape of the tank is coupled with both of its functions
- To carry out the primary function of storing pressurized air, the tank needs to have thick enough walls to maintain the air without rupturing. The high pressure inside the tank pushes out the surface area inside the tank so the thickness but be even.
- In order for the tank to support the entire electric motor and piston assembly systems, there needs to be some sort of flat surface to balance the subsystems on the tank. This requires for the tank to have extra parts welded to it.
- The tank is made out of steel
- This material choice is used for the design of the tank mainly for strength. Steel has a high Young's Modulus which gives it a high yield strength which is the number one concern. The material needs to be strong enough to maintain 140 psi of pressure.
- Global concerns are mainly the material. Steel is abundant in the world and use universally.
- Economic concerns would be that since steel is so abundant, it is cheaper than other metals.
- Societal concerns would be that steel is a sufficient metal to withhold the amount of pressure in the tank so that it doesn't fail and cause harm.
- Environmental concerns were not as considered because steel just like all metals is easily recycled.
The tank is painted Kawasaki green for visual aesthetics. It is the very first thing a consumer/operator would notice. The tank also has a very high surface finish. This is so no outside objects or occurrences can penetrate the tank causing failure and harm.
The tank had a couple different manufacturing processes.
- First the steel is cut and pressed to the specific thickness of the tank. Then the metal was bent into it cylindrical shape and welded. The two ends were also pressed and welded to create the elongated bubble effect. All other parts such as the handle, and support platforms were machined and then welded to the tank itself.
- The evidence that the tank was made this way is the welding beads around the perimeter of the diameter.
Manufacturing Complexity: This piece consists of 7 welded pieces on a green painted tank. These factors give this a rating of 8 on the manufacturing scale.
Interaction Complexity: This part interacts with the crank case, the wheels, feet and the handle. and is used everytime the compressor is used, as it stores the compressed air. It's rating is a 7.
Motor Cooling Fan
The cooling fan is used to cool the electric motor used in the Kawasaki air compressor.
- The component does not appear to be used for any function other than cooling the motor.
- The flows associated include that there is an in flow of rotational energy from the spinning shaft and an outflow of rotational energy in the fan which helps it to complete its main function of cooling the motor.
Since the air compressor is designed to be used outdoors or indoors, the fan is used in these environments as well. the cooling fan also operates near a large amount of heat( the electric motor) consistently.
Component Form (Geometry, Material, and Appearance)
The cooling fan is shaped similar to a disk with vertical blades along its outside circumference.
- The cooling fan is symmetric about the center axis.
- It is a 3 dimensional part, with a height, a radius and is continuous.
- The air cooling fan is approximately 10 ounces.
The shape of the fan allows it to properly cool the motor during operation. The symmetry does help to balance the fan, which spins with the shaft of the motor. If the piece was not symmetrical, it would be more difficult to balance. without the part being balanced it would produce unnecessary stress on the shaft of the motor.
The fan weighs roughly 1 lb.
The Cooling Fan is made from cast aluminum.
- aluminum was most likely chosen because of its low cost to manufacture and its strength.
- The material used for a cooling fan needs to be strong enough to survive centripetal forces associated with rotating tapidly, and be light enough in weight where it does not hinder the performance of the electric motor.
- Global factors taken into consideration would be, to have chosen a material available world wide, and almunium is used world wide.
- The societal factors taken into consideration would be if aluminum was locally available and what material cooling fans are generally constructed of, because of the weight and strength of it.
- The economic factors taken into consideration most likely had the largest impact on material selection. aluminum is cheap and easy to manufacture compared to similar metals.
- Environmental factors most likely had less of a role in choosing this material, However, aluminum is one of the most recycled metals. The manufacture would most likely not intend for the product to be recycled.
The Fan is most likely not seen, as it is covered by a large motor shroud.
- The fan is the same color as its material, it hasn't been colored because it is covered and cannot be seen.
- The fan has a rough surface finish from when it was cast.
- The surface finish has not been changed because it will not affect performance greatly, and it cannot be seen. machining a finer surface finish would only increase cost to manufacture the part.
The motor cooling fan was cast from aluminum.
- On the inside of the fan( the two holes drilled in the center), there are visible parting lines that travel horizontally.
- since aluminum was chosen because of weight and strength, casting the part was chosen because of its low cost and manufacture time.
- The cooling fan is a relatively simple shape, casting this part would be a straight forward process and would take the least time.
Global factors taken into consideration for choosing to cast the material, it is a common process world wide for producing aluminum parts.
Societal factors taken into consideration when choosing to cast the parts may have included the standard process used to manipulate aluminum.
Economic factors most likely had the greatest influence, as casting the material is the cheapest and fastest way to produce the parts.
Environmental factors that impacted the choice to cast, may have included the re-usability of the casting process.
Manufacturing Complexity: This part was die cast, and drilled and tapped to allow a set screw to bolt it to the motor shaft. no side actions were needed for the casting. 1 point awarded for the hole tapping the hole . this gives it a 3 for the rating, based on these factors, and its die casting.
Interactions Complexity: This part runs with the electric motor, every time the compressor is run. It connects to the motor shaft. These interaction factors gives it a rating of 4 according to our scale.
Solid Model Assembly
Below we have created 3D models of 5 integral parts within the Kawasaki Air Compressor using Autodesk Inventor.
Parts to be Modeled
The components we modeled include:
- Piston Sleeve
We decided to model the piston assembly because it is an integral part of the compressor. The shaft is rotated due to the electric motor, which rotates the crank, and pulls the piston and connecting rod up and down. The crank is balanced in order to smoothly rotate the piston/rod as a constant rpm without creating stress on the components. The rod also has an oil agitator which is used to stir up oil in order to help it reach and lube the proper components. The piston is connected to the rod via a sleeve which slides through the holes in the side of the piston and through the top end of the rod, and is clipped in by an expansion ring on each side. All these components and their reactions produce the compressors main function; to intake air and and pressurize it into a tank for later use.
The following are the individual 3D models we created, in addition to a full assembled model displaying all the parts and their respective connections with each other.
Before proceeding to manufacturing, there is a desire to analyze the sheer force exerted on the wrist pin when the compressor is at 140 psi and the piston is at top dead center (TDC).
- The pressure on the piston is 140 psi
- Diameter of the piston 1.887 in
- Pressure is not leaking past the piston rings
- Electric motor has stopped
- Wrist pin outer diameter 0.471in
- Wrist pin inner diameter 0.282in
- The wrist pin will not shear because of the rod
- Nothing break
When reviewing the calculations a 12,077,754 Pa seems extreme, but remembering that it is a Newton over a meter squared, brings this sheer stress into perspective. We are given a diameter and need a radius to calculate the surface area that the 140 psi will be applied to. Dividing the diameter by 2 will give us the radius of 0.944 in. An area of 2.80in2 makes sense and applying a force of 140 psi spread over the area of 2.80 in2 gives us a large force of 391.53 lb. converting from pounds to Newton’s we get 1742.31N as the force acting on the piston from the compressed air.
The units make sense, the area is in^2 or m^2 and the force is pounds or Newton’s and N/m^2 =Pascals.
A force of 12,077,754Pa is a realistic shear force on the wrist pin, because the air pressure acting on the piston is high and the piston has a significant surface area for the air pressure to act on, but the cross sectional area is minimal and so the force acting on it divided by the cross sectional area that is small giving an even larger number. Also the sheer force is Newton’s of meters squared, and because our cross sectional area is not even an inch squared, it can be expected to have a huge shear force. There are other factors that would affect real world usage of the compressor, and would adjust the sheer force, things like static friction verses kinetic friction. When the piston is in motion the kinetic energy will change the sheer force acting on the wrist pin. Our diagram and all measurements came from a model made after the original parts with as exact measurements as possible. In the design stages of the product, engineerings likely used these methods or similar ones to calculate the strength (or strength needed) of the wrist pin. There were likely also numerous tests done with a prototype compressor to test for strengths, stresses, and failures of the wrist pin and surrounding components. If failures or high stresses were recorded in testing, the component would need to be recalculated, redesigned and retested until proper strengths were achieved.
During the product dissection and component analysis, a few ideas for a design revision seemed to present themselves. These ideas include ways to address revisions in ergonomics, performance and product safety.
One way to improve the ergonomic design of the air compressor is to improve the physical parts of the compressor that the user interacts with. Since the air compressor is designed for portability, moving the product will be a common operation. One ergonomic issue with the air compressor is how the user can move the compressor themselves. The handles are in logical locations, for moving the compressor horizontally across the ground. However, if the operator needs to lift the compressor vertically into a vehicle or shelf it is much more challenging because of the geometry of the handles. Without the ease of moving this vertically, ergonomics is severely hindered. Ergonomics is a large societal factor that must be taken into account when designing a function. In order to improve the ability to lift the compressor, a smaller handle could be added to the end of the tank (the end with the larger handle). This would allow the user to pick the compressor up and have an even load in each arm. Without this, the small handle is grasped and the large handle, which makes the compressor physically awkward to lift vertically. The weight of the compressor could also be considered, although we feel that it would be very difficult to make the compressor physically lighter without damaging the integrity. The compressor casing, crank, rod, and piston are all currently made out of aluminum, which is one of the lightest and most common metals used for piston-cylinder assembly's and casings. Using this metal also dissipates heat better compared to iron, which is safer for the consumer. The tank could be substituted with one made of another metal, but that would also likely decrease its strength compared to the current steel one, which we feel is not worth saving a pound or so. We that adding a second "lift-handle" to the other side of the tank would provide enough support to easily lift the compressor, regardless of its somewhat heavy weight.
Improving User Safety
One major global factor in designing the air compressor that needs to be taken into consideration is user safety. During initial inspection, it can clearly be seen that the heat exchanger that moves air from the cylinder to the compressor is slightly exposed. If the user comes into contact with this heat exchanger, the operator may be burned severely. In Figure 54, it is clearly shown that when installing or removing the handle the user is in very close contact with a potentially hot component. Placing a small metal guard over this would greatly reduce the chances of injury or burn. This guard could be small bracket that is bolted on along with the crank case cover bolts. This would allow it to have a stable platform to mount on.
- User safety is of extreme importance and if a small guard was built around it, it would greatly reduce the chances of the user getting burned. This would increase cost negligibly and would give the overall product much greater safety rating, which is an ideal selling point.
A major improvement that could be made while maintaining similar costs is performance. By changing the compression rate a greater fill rate could be possible. A more efficient compressor would positively effect product recognition, which is an important societal factor.
If the crank shaft was extended downward, the connecting rod lengthened slightly, and a longer cylinder constructed, a longer stroke would be created by the piston. This effect would compress a greater volume of air during each rotation of the crank shaft, making the compressor a fair amount more efficient. The cylinder would have to be redesigned to ensure the TDC location of the piston is does not hit the valve. The compression ratio of a piston-cylinder system is its volume at BDC divided by the volume at TDC, both of which are shown in Figure 55. Due to the exhaust of the electric motor, which has been noted as the "air fill line" throughout this report, much less stress on the piston since there is minimal physical compression of air, except for in the tank. We feel that increasing the compression ratio will be make the compressor efficient enough to compete with a higher level air compressors, thus offsetting revision and additional material costs. In order to complete this revision, new cylinder bolts would also need to be used, as the cylinder itself would be increasing in height. This revision would fill the tank faster, which is ideal for the user and company in terms of advertising and price setting.