Group 25 - Snow Blower (Gasoline Powered)/Gate1
Craftsman Eager1 Snowblower
The purpose of this gate is to prepare for what will be encountered when the physical dissection of the product begins. Using the current knowledge we collectively possess on the topic, we will anticipate the different components and materials that will be found inside of the product as well as prepare for potential problems we may face during the dissection.
Tools Required For Disassembly:
- ¼ ‘’ through 1’’ Ratchet Sockets
- 5mm Through 25mm Ratchet Sockets
- Needle nose Pliers
- Crescent Wrenches ( ¼ ‘’ through 1’’)
- Medium sized Adjustable wrench
- Allan Wrench set
- Torx Wrenches
- Ring Clamp Wrench
Step by Step Breakdown:
The snow blower of selection is rather old and quite the complex piece of equipment in terms of assembly/disassembly. To help simplify the intended process of disassembly the snow blower has been broken down into four main sections of reference. These four sections are the Engine( which is composed of the motor/air filter/fuel tank/carburetor/starter), the Drive Train( which is the wheels/driving unit/internal gears/and belts), the Chute( which is the auger and its housing unit/ the chute/chute propeller/ propeller casing), and finally the Handles/Controls( which is the handles/throttle/chute adjuster). It will be much easier to read the process this way so to break the machine apart initially into these sections one must do the following:
- There are a series of cables that extend from the Controls to the Engine, to remove them simply slide the cable ends out of their clamps on the Engine Side.
- The crank shaft that connects the Chute to the Controls can also be removed by taking of the pin that holds it in place on the Chute side.
- Next step should be to remove the belts that are attached to the pulleys on the Engine from the Drive Train
- Now in order to separate the Chute from the Drive Train the auger must be removed. To do this there are several bolts that hold it in place and a differential case in the center, remove these and the auger should come right off with some prying possibly required.
- Last step will be to use the many different sizes of Ratchet Sockets to remove the bolts holding the Engine to the Drive Train, the bolts holding the Chute to the Drive train, and the Controls/Handle from the Drive Train.
At this point all four of the major sections are disconnected from one another and sitting individually in the desired work location. Now each section can be inspected piece by piece with relative ease versus attempting to inspect for certain things with the machine still assembled. In terms of section complexity the order will be the Handle/Controls, the Chute, the Drive Train, and last the Engine. Due to lack of field experience of the group members, an accurate hypothesis of what to expect and how to disassemble specific parts within the Engine and Drive Train cannot be given until work is actually conducted on the snow blower. Up to that point though inspection is rather simple but then could become quite complex.
For the Handle/Controls:
The cables that were used to control the fuel consumption rate of the motor and the wheel engage can be seen hanging from the throttle lever and the wheel engage lever respectively. With relative ease one could remove the screws that hold these levers in place if so desired. And as such the crack shaft that was connected to the chute can also be removed simply by breaking it into its sections and sliding it through the brackets that hold it in place.
For the Chute:
The Chute itself is composed of the auger, which should have already been taken off in order to remove this section, the auger housing, the chute, and the chute propeller with its casing that actually blows the snow up and out of the chute. To dissect this part there are 4 bolts that hold the chute to the propeller casing, remove them and it comes right off. Then there are just several bolts that hold the propeller casing to the auger housing to take off. After that all of the parts of the Chute section are disassembled and ready for inspection.
For the Drive Train:
To open up this box shaped unit, there are two metal plates that encase it held on by 8 screws. Once those are removed the entire inside of the drive train can be seen. With our current knowledge on this subject, it’s presumed that there is a gearbox that transfers power from the motor to drive the wheels if engaged from the Handle Unit. Because there are four forward speeds and one reverse on the shifter, it seems logical that there be a gearbox with five sets of gears to control how fast the wheels are driven.
For the Engine:
Once the engine sits by itself, it will be easy to remove the screws that hold the gas tank, air filter, carburetor, the electric start, and any other minor features that are in the way of removing the motor head. Now that everything has been removed, taking out the bolts that hold the head on will be the next task. With the head removed the top of the piston as well as the piston rings should be visible. Once the piston and the connecting rod are removed the crankshaft should be sitting directly below with the cam shaft next to it. After the removal of the camshaft and crankshaft, the main parts of the engine have been removed. With our current knowledge of gas engines, this is as far as we can speculate without physically disassembling the engine.
|Daniel Bachman||Project Manageremail@example.com||
||Arranges time for members to gather and work, also organizes each members tasks.||Get work done before the "last second"|
|ByungGun Song||Technical Managerfirstname.lastname@example.org||
||Designs the wiki pages and determines the layout and organization of the page.||Tell everyone to speak at a slower pace.|
|Matthew Kryzak||Wiki Researcheremail@example.com||
||Looks at wiki writing procedures and discovers solutions when they arrise in the page ppresentation.||Do what the group manager says and get work done earlier.|
|Michael Regis||Communication Managerfirstname.lastname@example.org||
||Figures the best method of vocabulary and presentation that will best connect with those looking into the project.||Do what group manager says and get work done earlier.|
|Jack Wong||Research email@example.com||
||Researches the history of the project and its uses and looks into possible improvements.||Talk more|
This dissection/analysis project will have many steps and there will be a lot to do over the semester so it is very important to set out with a well outlined plan. In order to keep everyone up to date on the project, group emails and text messages were been used to maintain contact. The group members met on a weekly basis and gathered after every class to discuss current progress of individual members and to further reinforce the tasks assigned. Outside of class the group would meet on either a Saturday or Sunday afternoon to pre-analyze the snow blower. In between our meetings we will delegate individual tasks that have to be completed by the time of the next meeting. For technical writing, meetings will be held at the Capen Hall library; however once Gate 2 begins there will also be meetings held at the dissection lab where most of the physical work will take place.
If any group conflicts were to arise they would be dealt with swiftly and justly. If there is a disagreement in the group we will enact a majority rule system where everyone will listen to each side of the disagreement, form their own opinion and vote for a side based on what they think is best for the good of the group. Because we have an odd number of group members there will always be a definite final say.
In order to keep on task and make sure we are caught up on the project, we will be assigning project roles to each of the group members.
The Craftsmen Eager-1 snow blower was developed and sold by Sears Hardware in the late 70’s and early 80’s. During the development cycle gasoline energy was widely available and cheap (abstaining the oil crisis of 1974, which was due to an oil embargo). Problems like global warming and the finite supply of oil were not at the forefront of everyone’s minds. As a result, the Craftsmen Eager-1 was not designed to be an efficient machine in terms of energy consumption. The machine was sold in the United States, in regions that experienced snowfall. It was designed to make the consumer’s life easier by replacing the often backbreaking work of shoveling snow with the simple task of pushing the snow blower.
- The craftsmen eager-1 snow blower is intended to ease the process of removing snow from one's property so that they may have greater freedom of travel without the hassle of traditional shoveling. The product draws snow in through the auger and then feeds it into an impeller. The impeller then throws the snow out of the chute in the user's desired direction.
- The Craftsmen Eager-1 is intended for personal use. It generates a small amount of torque and it has a small auger when compared to larger alternatives such as a commercial plow/snow thrower.
Four forms of energy are used in order for the snow blower to function. They include chemical energy in the form of a gasoline-air mixture, Electrical energy from the spark plug, heat energy due to combustion, and mechanical energy in the drivetrain and spinning auger. The Craftsmen Eager-1 utilizes a stock 5hp, 4-stroke gasoline engine. The engine cylinder imports chemical energy from the gas tank intake (gasoline and air). The gasoline in the cylinder of the engine is then combusted, with the help of a spark plug, causing heat energy to be released. The rapid rise in temperature (heat energy) causes an explosive expansion of the air in the cylinder, therefore driving the piston. The motion of the pistons represents the change from heat energy to mechanical energy. The pistons are connected to a crankshaft and cause it to rotate. The mechanical energy of the pistons is transferred to the crankshaft, and from the crankshaft to all subsidiary systems, such as the auger and wheels.
||Gasoline air mixture|
||Drive train and Spinning Auger|
After taking a closer look at the snow blower and using some assumptions based on my past experience with similar devices I have compiled a list of the components that make up this product. The list includes a total of 32 different components. Some components only show up once on the product but others appear a few times, in different forms and doing different jobs. Most of the components on this product are very simple and interact with other components in a pretty conceptually simple way however there are others that are a bit more abstract when it comes to looking at the job they do. One good example is the carburetor. This component does the job of taking in fuel and air in precise ratios and combining them to produce the fuel mixture that is ignited by the engine. The carburetor, like many of the other components and subsystems on the engine of the snow blower is conceptually more difficult to understand, requiring further knowledge of thermodynamics and heat transfer. However if we ignore many of the components involved with the engine, what’s left is pretty simple really. Many of the component interactions just rely on principals of statics and basic physics, like the gearing down effect you get from the pulley-belt component interaction.
System is the most complex as it contains the most small parts that are quite difficult to access without first disassembling other parts. It also runs under the largest stress as it performs combustion and its internals operate with the highest rpm. The rotational power that comes from the engine is applied to pulleys on both the auger and drive train systems.
- Pull start
- Starter motor
- Gas tank
- Spark plug
- Poppet valve
- Cam shaft
- Timing belt
- Distributor system
- Cylinder block
- Cylinder head
- Piston ring
- Rocker arm
- Valve spring
- Connecting rod
- Air filter
- Fuel filter
- Oil filter
- Oil pump
Drive System Components
The drive train is rather complex as it has many rotating gears and axles and chains moving around. It operates however with a much lower rpm and with simply romoving the top plate all inner components can be accessed at any time.
Snow Throwing Components
The Auger and Chute system is rather simple in that all components are already quite easily accessible without the removalof any panels. There are also the fewest parts of any of the systems.
- Helical auger
- Universal joint
- Sheet metal body panels
- Sheet Steel- mainly used in the construction of the housing of the snow blower. Thickness varies from about 1/16 to 3/16.
- Rubber- used to make the wheels as well as the various pulley belts and the cover to the spark plug.
- Cast Iron- the differential housing for the auger as well as the engine block are cast iron.
- Plastic- used in the housings for the cables, the grips on the handles and the knobs on the shifter and other lever controls.
- Aluminum- the piston contained inside of the engine as well as some of the drive train components could potentially be aluminum
- Copper- the coil in the starter motor is made of copper as well as the wiring that leads to the spark plug.
User Interaction Profile
The user interfaces with the snow blower through a lever that changes the gear/belt ratio of the engine and wheel axle in order to influence the speed of the snow blower. Handle bars are also available to aid in steering the machine. The user first has to make sure that the snow blower’s gear is in neutral. After that the user has to start up the snow blower by either pushing the electric start button located on the top of the snow blower or by pulling the a start cord that is located near the back of the snow blower. Next the user will hold down the clutch and move the gear handle to first gear to get it start moving. From there the user can either change the gear up or down to the desired speed. The user can also change the angle of the shoot to control which direction the snow will be blown to. The interface is very intuitive and simple. To get it started all you have to do is push the electric start button or pull the starting cord. To start moving the snow blower the only thing you would have to do is to hold the clutch and throw it into first gear. The shoot is also easily controlled by a lever near the handle bars. Required maintenance is relatively simple. It includes ensuring sufficient air is in the tires, changing the motor oil periodically, lubricating gears, replacing springs and bolts that have experienced wear and tear, ensuring that all the bolts and screws are tight, and filling the gas tank. Periodic cleaning of the outer surface may also be necessary to prevent gather up of dust and possible rusting.
Product Alternative Profile
||Better if the area to be cleaned is relatively small but requires more work.|
|Industrial Snow Thrower||
||Only good when uncovering very large areas and only if the customer has very deep pockets.|
||Good for uncovering large and smaller areas but requires a vehicle that it can mount to. Can also cut and chop up the surface it is uncovering.|