From DDL Wiki

Contents 1 About 1.1 Group Members 2 Product Study 2.1 Function 2.2 Input 2.3 Output 2.4 Normal Use 2.5 Special Considerations 2.6 Other Uses 2.7 Stakeholders 3 Product Dissection 4 Design For Environment (DFE) 5 Failure Mode Effects Analysis (FMEA)

About

This is the project Wiki for Team 8 in 24-441 Engineering Design Course. The product we have chosen to analyze is a car jack.

Group Members

• Matt Wasserman
• Alberto Guzman
• Saran Soongsawang

Product Study

Function

• Typically used to lift up the corner of a car, normally for changing a tire.

Input

• Crank, which rotates threaded rod

Output

• Vertical motion up or down that locks in place
• As a result of the design and upward motion imparts a force.

Normal Use

1. User kneels down in next to car.
2. Jack is placed flat under car.
3. Crank arm end placed into eyelet or car.
4. Crank arm held up in one hand and rotated clockwise with the other.
5. When upward motion of jack gets close to car frame, user aligns jack as necessary make sure it is securely aligned with the pinch weld on the car's frame.
6. User continues to rotate crank arm as the jack lifts the car until the desired height is reached.
7. After the user is done changing the tire the crank arm is rotated counter-clockwise until the jack is completely closed

Special Considerations

• Might be difficult for some users to kneel down next to car and reach under for correct placement.
• Depending on lighting, can be difficult to ensure proper alignment.
• When rotating crank arm it is easy to bash knuckles into the ground
• Must be careful (cannot rotate to fast, must be in right position) when rotating or else the entire jack, not just the threaded rod, rotates. The jack must then be repositioned. This is the case when the jack has not yet secured itself between the car and the ground.

Other Uses

• Separating two objects
• Bending Pipe
• Lift heavy objects
• Push heavy objects.

Stakeholders

• Car driver/passenger (user)
  • They must use the actual product
• Car Manufacturer
  • They must contract to another company or design and manufacture a jack to go with each automobile
• Jack manufacturer, if not part of car company
  • They must design and build the jack for the car company or as an after-market replacement
• Employees of car or jack manufacturer
  • They play a role in the design or manufacture of the jack and are paid for that role
• Business and employees that sell after-market jacks
  • They sell and make a profit off of the after-market jacks
• Suppliers and distributors of after-market jacks
  • Supply and distribute after-market jacks to companies to sell

Product Dissection

Documentation of Car jack product dissection

Design For Environment (DFE)

This style of car jack (manual screw jack) will require no renewable energy input during its construction. Energy will be needed to produce the steel used by all of the parts. Energy will also be used to run the machines that do the stamping/forming/assembly of the parts. Unlike hydraulic jacks which may require oil during there usage cycle this jack has been lubricated at the factory for the life of the product. The only input of energy needed during usage is work from the user.

This jack is made entirely out of steel. Parts have been coated with either a powder coat or some form of electro plating to protect them from the elements. Since all parts of this product are the same material recycling it would not require manual disassembly. The entire product could be shredded and sold as scrap steel to be recycled.

Failure Mode Effects Analysis (FMEA)

Item & Function	Failure Mode	Effects of Failure	S	Causes of Failure	O	Design Controls	D	RPN	Recmd Actions	Responsibility & Deadline	Actions Taken	S	O	D	RPN
Car Jack, used to lift corner of a car	Structural Failure	Car drops, can injure user, damage car	9	To much downward force, component failure	5	Ensure that the jack can be produced consistently with a high factor of safety	5	225	-	-	Preliminary FEA of jack showed approx 22,000 lb could be placed on jack before failure	3	2	5	42
	Rusting of jack over time	Failure of jack	9	Steel the material of the jack, can rust over time making it brittle	5	Make sure that coating is well applied	5	225	-	-	Steel coated to protect from elements, also placement during storage keep it protected from elements	3	3	5	45
	Car falls off of jack	Car drops, can injure user and damage car	9	Useage of jack on uneven ground Misalignment of jack with frame	7	Detection not possible from a pre-release standpoint	1	63	Study base more indepth to see how well it adapts for uneven ground, and study connection point with car frame	Alberto Guzman Matthew Wasserman	Include more written and pictographic documentation with and printed on jack saying to use on level ground	7	6	1	42
	User getting under car	User injury	9	Small workspace easy to be injured, car falling off of jack	4	Detection not possible from a pre-release standpoint	1	36	Study base more indepth to see how well it adapts for uneven ground, and study connection point with car frame	Alberto Guzman Matthew Wasserman	Include more written and pictographic documentation with, and printed on jack, saying to use on level ground, not to get under jack, and to keep hands away from pinch points	7	4	1	28
	User gets fingers/hand caught in pinch point	User injury	9	Careless or uninformed user	5	Detection not possible from a pre-release standpoint	1	36	Study pinch points	Alberto Guzman Matthew Wasserman	Include more written and pictographic documentation with, and printed on jack, cautioning about the pinch points	7	4	1	28
	User not using device as intended	User injury, damage to other items	9	Any number of reasons including jack slipping or applying too much force	2	Detection not possible from a pre-release standpoint	1	18	Think about how often this happens, general user stupidity	Alberto Guzman Matthew Wasserman	Include more written and pictographic documentation with and printed on jack saying to use on the device as intended	7	2	1	14