GATE 3: Product Evaluation
Contents |
Component Summary
Transmission Components:
Table 1.1: Described below are the components that make up the Transmission System
Clutch Components: Table 1.2: Described below are the components that make up the Clutch System
Engine Block Components:
Table 1.3: The components of the Engine Block are described below
Engine Head Components:
Table 1.4: The components of the Engine Head are described below.
Carburetor Components:
Table 1.4: The components of the carburetor are described below.
| Name | Function | Materials used | Manufacturing Processes | Number of times used | Image |
| Throttle Stop Cable | Changes the position of the Throttle | Rubber | Molded | Four (one for each carburetor) | |
| Throttle Stop Spring | Applies a force on the Stop Cable and causes the cable to return to its idle position when the normal throttle operating system fails | Stainless Steel | Formed | Four (one for each carburetor) | |
| Choke Bracket | Positions the choke cable securely | Billet Steel | Shaped | Four (one for each carburetor) | |
| Piston Diaphram Spring | Provides resistance for the diaphram to move up and down inside the carburetor | Zinc Plated | Formed | Four (one for each carburetor) | |
| Vacuum Chamber Cover | Keeps the air in the carburetors | Plastic | Molded | Four (one for each carburetor) | |
| Float Chamber Plug | Drains the Carburetors when needed | Titanium | Machined | Four (one for each carburetor) | |
| Throttle Stop Screw | Stops the engine from increasing its Rotations Per Minute and over heating | Steel | formed | four (one for each carburetor) | |
| Throttle Plate | Rotates to control the amount of air entering the carburetor | Steel | Machined | Four (one for each carburetor) | |
| Needle Jet | Supplies fuel to the chamber depending on the position of the throttle plate | Steel | Machined | Four (one for each carburetor) | |
| Float Chamber | Contains the fuel chamber, float pin and the needle valve | Brass | Grinding | Four (one for each carburetor) |
Intake Components:
Table 1.6: The Intake Components are described below
Product Analysis
Piston:
Component Function:
The main function of the Piston is to transfer the force provided by the expanding gas that’s present in cylinder, of the piston sub-subsystem, through the connecting rod to the Crankshaft. Each of the four strokes of the piston creates a new function. The downward stroke creates a vacuum, which sucks a fuel/air mixture into the chamber. The Compression stroke compresses the mixture and is ignited by the spark plug. Next comes the Power stroke which creates a mechanical force as a result of the ignition. The final stroke, the Exhaust stroke, releases gases through an exhaust valve that remained after the mixture was ignited and burned. Flows associated with the Piston include............The Piston functions in an environment within the Engine Block and that is related to two camshafts (intake and exhaust), valves, spark plugs, connecting rods, and the crankshaft.
Component Form:
The general shape of the piston is cylindrical and is axis-symmetric. It is primarily in three-dimensions. The piston is roughly six and one-half centimeters in diameter and four and three-quarters centimeters in length and weighs approximately from 0.5 to 1.0 pounds. The shape of the piston is important because it conforms to the always-changing dimensions of the cylinder bore. When cold, it is designed to be elliptical and when at the operating temperature the bore becomes circular. It is made from a mixture of an aluminum and silicon alloy. The amount of silicon determines the amount of strength of the piston versus wear properties and also controls the rate of expansion of the piston. More silicon allows the piston to be machined easier........
Manufacturing Methods:
Die Casting and Machining were used to make the Piston. This is evident in the complexity of the shape and the need that it be consistent every single time. Die casting is one of the more popular manufacturing methods used on metals and is very precise. Also, many pistons would have to have been made for such a high volume company and therefore needed a cost effective way of making this particular part. Silicon makes the piston easier to be machined into.....
Spark Plugs:
Component Function:
The Spark Plug's only purpose is to ignite the compressed fuels within the piston at specific points in the otto cycle. Flows associated with the component include.........The spark plugs work in an environment that consist of the camshaft and valve system, and the piston and cylinder system.
Component Form:
Spark Plugs are very small and their general shape is that of a cylinder. It is axis-symmetric on only one axis. It acts primarily in one-dimension due to the fact that it has no motion and just lights the gas at one end of its small tip. They are roughly four centimeters long and about three-quarters in length and weigh only a couple of ounces. Its shape is important because its small enough to be placed in the piston system between the valves. Also since the overall body gets thicker towards the midsection it assists in sealing up the chamber of the piston. The Spark Plugs are made up of several different materials including porcelain, an aluminum oxide ceramic for the insulator tip and several other metals that make up the rest. The insulator and electrode's materials were decided to be used since they kept the plug from burning............
Manufacturing Methods:
Several manufacturing methods were used to create the spark plug, which include forming and molding or extruding and die casting, then machining or knurling, rolling, and then further molding .......
Camshafts:
Component Function:
The function of the camshaft is to rotate while its protruded lobes push on the valves to let air/fuel mixture into the piston and the other releases the exhaust gases from the piston. It also helps and keeps in sync with the rotation of the crankshaft which is very important in timing in the otto cycle. Flows that are associated with the component function include........The camshaft performs in the engine head, and functions along with the valves and timing chain, and therefore indirectly with the camshaft.
Component Form:
The general shape of the camshaft is a long cylindrical rod with oblong lobes that protrude from it and on one end is a gear. It has a flywheel at one end that connects to the timing chain. It primarily does work in two-dimensions since it rotates about an axis. The shape of these shafts are important because the lobes are intelligently placed so that when the shaft rotates they push on the valves to open them up at the exact time that it is needed. It is about 32 cm long and two centimeters in diameter for the rod. The lobes protrude out about two more centimeters and the flywheel has a diameter of about five centimeters. The weight of camshaft is roughly two and one-half pounds. It is made out of an iron-cast since it is easier for high volume production then steel.....
Manufacturing Methods:
The Camshaft is made by methods of turing and milling..........
Crankshaft:
Component Function:
The function of the Crankshaft is to translate linear motion for the pistons into rotation. The rotation of the crankshaft will indirectly cause the wheels of motorcycle move. Also, the rotation of the crankshaft is timed perfectly with the camshafts through the timing chain. Flows associated with the Crankshaft include.......The crankshaft functions within the engine block and is conncected to the timing belt and pistons
Component Form:
The general shape of the crankshaft is a long rod with square shapes that extend off of the rod to help translate the motion. It is noticeably an awkward shape and looks like a "maze". It works in primarily two dimensions since it also rotates about a single axis creating torque. The crankshaft's shape is important because the square-shaped extensions off of the shaft are pushed by the connecting rods to help translate the motion from the piston to the crankshaft. It has dimensions of 42.8 cm in length and two diameters of 8.2 and 10.6 cm and weighs roughly 20 to 30 pounds. It is made from steel because strength is needed to withstand stress. Any weaknesses could cause problems with the bike..............
Manufacturing Methods:
The Crankshaft is forged and then machined. This is evident since no parting lines are visible and since forging is used to create stronger parts which is need in the crankshaft.........
Filter:
Component Function:
The only function of the air filter is to remove solids from the air so that only clean air enters. Flows associated with the Air Filter include........The air filter functions above the engine head and connected to the intake.
Component Form:
The shape of the Air Filter is square and is about six inches in width, a foot in length, and roughly one inch in depth. The weight of the filter is less than one pound. It contains levels of material, that look like ripples, parallel to each other and is symmetric along two axes. It primarily performs in three dimensions since air will maintain a loading across the filter and will come from all directions. The shape is important because the air flows through the filter in between the parallel levels which then collects the dirt and dust. The filter paper is made from filter paper and housed in a plastic casing. Decisions that impacted this was the fact that the paper was cheap and effective........
Manufacturing Methods:
Manufacturing methods that made this part were injection molding for the plastic casing and linear extrusion for the filter paper. The plastic has evidence of parting lines and riser marks which suggest is was manufactured in a mold. As for the filter paper, the lack of thickness and evidence of the ripple effect show that the paper was extruded. Both the material and shape impacted the method of manufacturing.
Component Complexity
| Roman Numeral | Name of Item | Precision Accuracy | Quality | Manufacturing Process (Complexity) | Overall Size |
| I | Alternator | 1 | 3 | 3 | 2 |
| II | Intake Filter | 1 | 2 | 1 | 1 |
| III | Fly Wheel | 3 | 3 | 2 | 1 |
| IV | Timing Chain | 3 | 3 | 2/3 | 1 |
| V | Pistons | 3 | 3 | 3 | 2 |
| VI | Carburetor | 2 | 2 | 3 | 2 |
| VII | Clutch plates | 1 | 2 | 1 | 1 |
| VIII | Camshaft | 3 | 3 | 3 | 2 |
Table 1-2
Meaningful Scale
Precision Accuracy: This section defines how accurate the component might have been to allow the engine to run with no problems.
Quality: This defines the quality inspection required on this component before it left the factory. Certain components of the engine must pass a minimal requirement, so that failure during ware and tare does not occur.
Manufacturing Process: This section defines the complexity of the item related to manufacturing. In other words, how easy can the item be duplicated or manufactured? Can a machine reproduce the component easily?
Overall Size: This section compares the component to the overall size of the engine.
How do the three categories above impact complexity? Depending on the component, certain accuracies, materials, and quality must all be present. The Camshaft for example, must have high precision when being manufactured because the camshaft operated valves that control intake and exhaust. Minor errors and accuracy can result and poor overall performance of the motorcycle. Quality and material are important because quality assures that the item can go through a long period of wear and tear without breaking down. A minor defect can cause total failure of the engine. For example, going back to the camshaft, if this component were to suddenly fail, the whole overall process of the engine would fail and damage can occur within. Materials are important because within an engine, temperatures can reach a couple hundred degrees. Certain materials must be used according to their characteristic. Lastly, the overall manufacturing process of an item can determine the cost and availability of the component is. If the component is difficult and costly to produce, then availability of the item would be limited **SEE CHART FOR COMPONENT RATING
How complex are the interactions? Depending on the component, interaction complexity can vary. For example, the timing chain interacts with the camshaft, and then to the valves, which deal with intake and exhaust etcetera. So the timing chain would have a high component interaction rating. The exhaust pipe rating would be low because this component only functions with the exhaust fumes from the combustion chamber.
Solid Modeled Assembly
Figure 1. Piston
Figure 2. Piston Cylinder
Figure 3. Wrist Pin
Figure 4. Connecting Rod
Piston
Piston, moves inside a cylinder between BDC (Bottom Dead Center) and TDC (Top Dead Center) compressing air and fuel mixture to get pressure. Its translate heat energy to the mechanic energy. The pressure is transmitted to the crankshaft by a connecting rod. Firstly, air and fuel mixture comes to cylinder by intake valve. At that time, piston is at BDC. Piston moves up by crankshaft to compress the mixture. At that time, the piston is at TDC. The expanded gas pushed the piston at BDC and the crankshaft spins. Combusted gas exits by exhaust valve. (1)
Connecting Rod
It connects piston to crankshaft. One side of a connecting rod is connected to piston by wrist pin, and other side is connected to crankshaft by crankpin. Connecting rod converts axial movement which is done by piston in cylinder to rotary motion which spins crankshaft. (2)
Crankshaft
Crankshaft is connected to pistons by connecting rod. It translates the linear energy into a rotational energy with its arrangement. Pistons move up and down with the arrangement. Also, it is connected to flywheel which lays kinetic energy in. (4)
Cad package
The CAD Package used was Autodesk Inventor 2010 The connecting rod is fasten to the crankshaft by the tread. Wrist pin connects the connecting rod to the piston. When the piston moves up and down, it obtains bearing to the connect rod. (3) In the Honda engine, it was made from steel, which provides very high strength, and hardness.
Engineering Analysis
Engineering Analysis
Problem Statement: How long would it take for the motorcycle to completely come to a stop with the force of friction and a 125N force of engine braking applied?
Statement of Assumptions:
-The motorcycle velocity = 40 mph ~ 17.8 m/s
-Force of the engine braking – 125N
-Mass of the bike = 295lb ~ 133.8 Kg
-Coefficient of Friction between rubber and gravel road = .55
-Drag Force applied to the body and Bike are ignored
-Treat the body and bike as a point object
Governing Equations:
Normal Force = m*a
Magnitude of Static Friction Force = μk*N
Initial Energy = Final Energy = (½ mv2+mgy = ½ mv2+mgy)
Motion with Uniform Acceleration = X=Xo+Vot +1/2 axt2
Calculations:
Normal Force = (mass)(acceleration)
= (113.8kg)*(9.810m/s2)
= 1311.2.kg* m/s2 (Newton (N))
Magnitude of Static Friction Force = μk*N
= (.55)*(1311.2kg* m/s2)
= 721.2N
Energy Final = ½ (113.8kg)(17.8m/s)2 + 0 – f*d – (Force of engine braking)
0 = (2.12E4N-m) – (721.2N)*d – 125N
-(2.12E4N-m) + 125N = -(721.2)*d
29.2m = d
X=Xo+Vot +1/2 axt2
29.12m = 0 +17.8m/s(t) +0
29.12m/ 17.8m = (t)
1.64s = (t)
Solution Check:
After looking at the equations used to find out the time it would take for the bike to come to a stop. All the units cancel out and it makes sense for the weight and the speed, it would take 1.64s to stop.
Discussion There are many other factors that are taken into account in this situation, but for calculation purposes and knowledge wise, what is stated above can calculate the distance and time it would take for a motorcycle to stop if an initial velocity is given.
Design Revisions
Design Revision #1 (Fuel Injected) Now days it is rare to see a newer motor of this size that is not fuel injected. The fuel injected system allows so many advantages (listed below) in comparison to having a carburetor. In order to make our Honda engine into a fuel injected engine a few things would have to occur starting with the carburetor (subsystem) being completely removed from the engine. You are going to need to add, injectors, vacuum lines, an Engine Control Unit and a fuel pressure regulator. All of these are necessary in order to successfully add a fuel injector to a carburetor ran engine. Although it may be a lot of work to change this part of the motor it is worth it for the following reasons:
• Less maintenance
• Higher engine performance
• Better fuel efficiency
• Easier to start and run the engine
• Reduced emissions
• Overall better control over how the engine runs
Four Factors
When we look at the environmental concern of adding fuel injection one can see that the increase in fuel efficiency directly impacts this concern. The higher fuel efficiency means that the engine will be using less gasoline which in turn means less emissions. When looking at the economic aspect we see that adding the fuel injection system may be a little costly, however, when you add in that there is an increase in fuel efficiency that adds a great selling point to the public. Society is always begging for higher performance and the best technology at the time and with fuel injection we have both of these.
Design Revision #2 (CVT) The second revision that we would suggest would be the addition of a CVT (Continuously Variable Transmission). This type of transmission is new technology for many people and has been seen on snowmobiles and now a few makes of Nissan. The CVT transmission has the ability to provide an unlimited range of gear ratios in the transmission. A CVT uses a pulley and belt system to provide an unlimited range of gear ratios. It is different from the Honda transmission which has a set number of gear ratios. A CVT uses parts such as a high density rubber/metal belt, a driving pulley actuated by a hydraulic cylinder, a mechanical torque-sensing driving pulley, sensors and microprocessors to perform its function. In order to add this transmission the old subsystem transmission would have to be completely removed and replaced with the CVT. The CVT transmission comes in a set package but does include the parts listed above. For the following reasons the CVT motor is highly recommended:
• Improved fuel economy
• Less emissions
• Quicker acceleration
Four Factors
When looking into the four factors one can find many reasons that this would be a good change to the motor. The decrease in emissions is a huge selling point for the economic concern. People like to see that they are helping out the environment while getting the type of motorcycle they want. The improved fuel economy is also a great selling point along with a good reaction for the environment. The quicker acceleration will make those performance frenzy people in society fall directly in love with the design revision. The only bad part to this revision is the economic cost, but overall the addition of the CVT would be great for all aspects.
Design Revision #3 (Supercharger)
The best way to improve the performance of the engine dramatically would be to add a supercharger. You would have to add a subsystem that connects the exhaust to the intake. A supercharge compresses air and then forces it into the internal combustion chamber. By compressing air and then forcing it into the internal combustion engine of the bike, the supercharger increases the overall density of the air inside of the engine. The result is that the engine system itself becomes more powerful. It is suggested to do this because it will allow:
• Higher performance
Four Factors By Adding a supercharger to the Honda Engine we look directly at the change in performance of the bike. This mainly concerns the societal aspect of revision because people demand higher performance and a supercharger will give them this. Economically the cost of the bike would increase, however, with the demands of people and performance this should not be a big factor. Overall, the addition of higher performance in a supercharger will attract adrenaline junkies and should cause little problem in selling this engine.
REFERENCES:
(1) Piston (n.d.). In Wikipedia, The Free Encyclopedia. Retrieved December 8, 2010, from http://en.wikipedia.org/wiki/Piston
(2) Connecting rod (n.d.). In Wikipedia, The Free Encyclopedia. Retrieved December 8, 2010, from http://en.wikipedia.org/wiki/ Connecting rod
(3) Piston pin (n.d.). In Wikipedia, The Free Encyclopedia. Retrieved December 8, 2010, from http://en.wikipedia.org/wiki/Gudgeon pin
(4) Crankshaft (n.d.). In Wikipedia, The Free Encyclopedia. Retrieved November 17, 2010, from http://en.wikipedia.org/wiki/Crankshaft
(5) Engine Assembly (n.d.). In Ford. Retrieved November 17, 2010, from http://www.fordscorpio.co.uk/manual/engines/dohc16v/DOHC16VDismant.pdf




