Door damper

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Revision as of 13:27, 17 September 2012 (view source) Msaitta@andrew.cmu.edu (Talk | contribs) ← Older edit		Revision as of 13:36, 17 September 2012 (view source) Msaitta@andrew.cmu.edu (Talk | contribs) Newer edit →
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	== Product Function and Evaluation ==		== Product Function and Evaluation ==
		+
		+	The door damper has two main roles.  First, the damper closes the door automatically.  Secondly, the damper ensures that the door moves at a safe and controlled rate.
		+
		+	Self closing functionality is achieved with the use of a spring.  The spring is compressed when the door is open.  It then expands and forces the door into a closed position.
		+
		+	Speed is controlled by moving a piston through a viscous fluid.  Speed can be controlled by opening additional channels to allow the fluid less head loss.
		+
		+	Motion is controlled and transmitted through the use of a two bar linkage, a rack, and a pinion.  This provides both mechanical advantage for the spring, as well as allowing the use of a linear spring to cause rotational motion of the door.
		+
		+
		+	'''Steps for use'''
		+	*Install door closer to door and frame
		+	*Adjust to desired angle and closing speed
		+	*Push/pull door open
		+	*Allow door to close behind you
		+
		+
		+
		+
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	| <1		| <1
	| o ring Picture		| o ring Picture
		+	|-
		+	| 8
		+	| Thin washer
		+	| 2
		+	| provide spacing between pinion and bearing
		+	| Stamped
		+	| Steel
		+	| <1
		+	| washer Picture
	|-		|-
	|'''Linkage'''		|'''Linkage'''

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Revision as of 13:36, 17 September 2012

Contents 1 Executive Summary 2 Primary Stakeholders and Product Needs 3 Product Function and Evaluation 4 List of Parts 5 Design For Manufacturing and Assembly 6 DFM &DFA 7 Failure Mode and Effect Analysis 8 Design for Environment 9 Team Members 10 References

Executive Summary

Primary Stakeholders and Product Needs

Consumers are building owners who must absorb cost of original door damper, instillation, as well as maintenance costs and replacement. Also must consider installers (construction workers), maintenance workers, and building planers.

Stakeholder	Needs
Consumer	Low Cost Reliable Ergonomic - easy to push door open and closes door at safe speed Maintainable Easily Installable Appearance - Do not want something too large or distracting Safe for users and maintenance personnel
Retailers	Returns a profit Easy to store and move Replacement parts Durability Reasonable price
Manufacturers	Use of stock parts if possible Few components to reduce production costs Inexpensive materials and processes Easily manufactured materials Easily assembled
Shipping/Transport	Lightweight and small – reduce fuel costs and space requirements Not easily broken – no special shipping considerations

Product Function and Evaluation

The door damper has two main roles. First, the damper closes the door automatically. Secondly, the damper ensures that the door moves at a safe and controlled rate.

Self closing functionality is achieved with the use of a spring. The spring is compressed when the door is open. It then expands and forces the door into a closed position.

Speed is controlled by moving a piston through a viscous fluid. Speed can be controlled by opening additional channels to allow the fluid less head loss.

Motion is controlled and transmitted through the use of a two bar linkage, a rack, and a pinion. This provides both mechanical advantage for the spring, as well as allowing the use of a linear spring to cause rotational motion of the door.

Steps for use

• Install door closer to door and frame
• Adjust to desired angle and closing speed
• Push/pull door open
• Allow door to close behind you

List of Parts

Part #	Part Name	QTY	Function	Manufacturing Process	Material	Weight (g)	Image
Body
1	Shell	1	Contain other parts and hydraulics	Cast	Aluminum	715	pic here
2	Rack	1	Move through viscous fluid and create damping	Cast/machined	Steel	352	rack pic here
3	Pinion	1	Transmit motion	Cast/Machined	Stainless Steel	150	Pinion pic here
4	Spring	1	Return door to closed position	Drawn	Steel	218	spring pic here
5	Side Cap with bearing	2	Allow pinion to rotate	Casting	Aluminum	24	Side cap picture
6	End Cap	1	Keep fluid contained, allow access for assembly	Cast	Aluminum	1	End Cap Picture
7	O-ring	1	Keep fluid contained, prevent leaks	Extruded and vulcanized	Rubber	<1	o ring Picture
8	Thin washer	2	provide spacing between pinion and bearing	Stamped	Steel	<1	washer Picture
Linkage
7	Large arm	1	Connect to door base	Cast	Steel	374	large arm pic here
8	Small arm	1	Connect to doorframe	Cast	Steel	81	small arm pic here
9	Threaded arm	1	connect to doorframe base/ adjust length of linkage	Cast	Steel	116	threaded arm pic
10	Washer	1	Hold linkage together	Stamped	Steel	3	Washer pic here
11	Nut	1	Hold threaded arm to short arm	Cast	Steel	6	nut pic here
12	Short screw	1	Hold linkage together	Cold headed and machined	Steel	3	Short screw pic here
13	Standoff	1	Connect to doorframe	Stamped and bent	Aluminum	6	Standoff pic here
14	Arm screw to box	1	Hold long arm to base	Cold headed and machined	Steel	6	arm screw to box pic here

Design For Manufacturing and Assembly

DFM &DFA

Failure Mode and Effect Analysis

Design for Environment

Team Members

References