Group 11 - Dual Stage Snow Thrower (Gasoline Powered) - Gate 4

Revision as of 14:22, 30 November 2012

Intro

In this stage, we reassemble the machine, examine the most crucial mechanism, and propose some possible design revisions to the machine.

Final Critical Review

Product Reassembly

Mechanisms

1. Spur gear: It is the simplest type of gear. It consists of a cylinder with the teeth projecting radially, and although they are not straight-sided in form, the edge of each tooth is straight and aligned parallel to the axis of rotation. The single spur gear is used to make the whole gear system more stable.
Specs:
Number of teeth=13
Module =2.33
Face width= 18 mm
Diameter of outside circle= 35 mm

2. Bevel Gear: It is specifically crow gear. Crown gear is a particular form of bevel gear whose teeth project at right angles to the plane of the wheel; in their orientation the teeth resemble the points on a crown. This crown gear is meshing with spur gears. Then the crow gear interacts with the two spur gears.

Number of teeth = 26

3. Worm Gear: A worm gear is sharing the same axle with the spur gear; the spur gear rotates with the bevel gear and rotates the worm gear. They have the same angle velocity. Worm gear motivates the discharge chute to direct the snow's outlet.

Possible Design Revisions
(Note: As previously stated, the title is misleading. The Toro CCR-2000 is a single-stage blower.)

1: Wider intake scoop. This would require a longer auger, a wider upper shroud, and a smaller reduction ratio on the pulley.
Global factors: The blower would be able to handle more snow at a time<.br /> Societal factors: Its improved capacity means it takes even less time and effort to clear the same area. That is less time for the operator to spend outside in the freezing cold.
Economic factors: By having to go back and forth less times while running the engine, this revision saves time, money, fuel, and maintenance needs, making the machine pay for itself sooner.
Environmental factors: Less time spent in operation means less overall pollution from the combustion engine.

2: Add an icebreaker auger, making it a dual-stage. The second auger will be larger, but will rotate much more slowly. It will also be made of steel, with blades to loosen up the snow and break apart ice. It will require a more powerful engine, an additional axle and pulley system, and a metal intake shroud to efficiently support the weight.
Global factors: The blower will become a heavy duty machine instead of a light duty one.
Societal factors: This revision would make the blower ideal for areas with heavy snowfall or icing problems.
Economic factors: It will be more expensive in materials and fuel, since there would be a good amount of metal to be machined and added to the blower. Metal is much more expensive than ABS plastic, and the extra weight would tax the engine more.
Environmental factors: Because of the need for a more powerful engine, it will burn more fuel at a time. However, it will burn less overall compared to using a light duty machine for heavy duty work.

3: Change to a 2-cylinder engine. This may require an enlarged chassis and a larger capacity fuel tank.
Global factors: The blower would be capable of operating faster and more consistently. It would also be capable of dealing with heavier loads, though not as heavy as a Dual-Stage blower.
Societal factors: A more powerful engine keeps the operator warmer and completes the job faster. Some users also like to show off or brag about a more powerful engine.
Economic factors: The machine will cost more, and use more fuel at a time.
Environmental factors: A 2-cylinder engine burns more fuel at a time than a single-cylinder engine. This revision will increase pollution from exhaust gases.

Procedure

Difficulty scale
1: Simple and quick. One person could do it in 5 minutes at most.
2: Complicated or tedious. The step is a little tricky or takes a long time.
3: Complicated and tedious. Two people are required for the task and the process takes time to complete.

Step	Difficulty	Tools Used	Actions
Step 1	?	?	?
Step 2	?	?	?
Step 3	?	?	?
Step 4	?	?	?
Step 5	?	?	?
Step 6	?	?	?
Step 7	?	?	?