Dishwasher

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Haier HDT18PA

Contents 1 Executive Summary 2 Major Post-Production Stakeholders 3 Product Use and User Study 4 Mechanical Function 5 Mechanical Use 6 Bill of Materials

Executive Summary

Major Post-Production Stakeholders

Customers: The customer has the most at stake and need for any product, in this case a tabletop dishwasher. The primary need customers would have for this product is to effectively clean dirty dishes while being more efficient than hand washing. However, this is not to say that needs satisfied by this dishwasher are also satisfied by all other dishwashers. What sets this unit apart is its small size, non-permanent installation, and easily removed plumbing connections. Satisfying these needs results in a better product and a greater demand to buy it.

Retailers:The needs of a retailer are dependent on those of the customer. In order to make a profit from the sale of this product, retailers need it to be in demand, have the right price point, and be marketed well. If these needs are not satisfied, the product will never find its way to a customer's home.

Transporters: Those who transport the product also have a stake in it. The products packaging must meet both the needs of being shipped from the manufacturer to the retailer and being shipped from the retailer to the customer. In the latter case, portability is again a need. This dishwasher will easily fit in the back seat of a car unlike a conventional dishwasher.

Product Use and User Study

Use of this dishwasher is not that difficult and very straightforward. First, a hose is attached directly to a faucet to act as a water source. Second, another hose is placed in a sink or drain to allow the waste water to be removed. Third, the user loads their dishes into the unit, applies the right amount of detergent, and then selects either a normal or heavy wash cycle. All that remains is for the user to wait until their dishes are clean. The device automatically shuts off when the cycle is complete, and the user removes the dishes from the unit.

Since receiving the unit three weeks ago, it has been tested on both the normal and high cycles by members of our team. Also, a user study was conducted with two students that are not party to this project. Their experience with the device will be summarized below. In this section we will simply share our experience while using the product.

Installing the product was of little difficulty and did not require much time. With the device installed, we then set out to find some of the dirtiest dishes we could. Since testing occurred in a house occupied by five college students, this did not take long. Dishes and cups dirtied with dried on chili, milk, oatmeal, spaghetti, and soup were all used since they were prime candidates for testing. These dishes were then loaded into the device. In order to compensate for any dish being too clean, large amounts of maple syrup were doused on the dishes while in the device. We closed the door, hit the button, and then hopped for the best. There was approximately a minute delay before the product began to function. The operation of the device sounded like that of any other normal dishwasher with the exception of seeing the waste water being removed. Approximately 45 minutes later the dishes were very clean. The following pictures show this process with components of the device labeled as they appeared before product dissection:

In the user study, test users were asked to list the steps taken to operate the device, good and bad qualities about the device, his feelings on the robustness, effectiveness, and ease of use of the product. Finally they were asked to list any potential changes that should be made to the device.

Mechanical Function

After seeing the unit operate through full cycles several times and before product dissection, we have determined that the device functions as follows. A pump contained with the unit's housing draws water from the faucet. This water is then pumped through some kind of heater where it is allowed to come up to temperature. This hot water then pools in the main chamber where it is combined with detergent. Next, the pump begins to either pull new water from the source or pump the pooled water through the rotating spray nozzle in order to clean the dishes. After the cycle is complete and via a second waste pump, all water is then drained from the chamber and discharged to a sink by passing through a trap in order to remove an particulate matter. This process is then repeated several times depending on the type of cycle that was selected. The dry cycle simply heats the air in the unit. The instruction manual also offers a quick approximation of how the device functions: http://www.haieramerica.com/en/asset/product/dec20a2ae2

Mechanical Use

Bill of Materials

The following is a bill of materials containing many individual parts and sub assemblies.

Part Number	Name/Description	Function	Material	Manufacturing Process	Mass	Quantity	Picture
1	Silverware tray	Hold silverware	Plastic	Injection molding	.125 kg	1
2	Dish tray/basket	Hold dishes	Plastic coated	Assembled	1.755 kg	1
3	Plastic wheels and axels	Movement of basket	Plastic	Injection molding	.025 kg	6
4	C-clip for sprayer arm	Attachment of sprayer	Plastic	Injection molding	.005 kg	1
5	Washer for sprayer	Allow for rotation of sprayer	Plastic	Injection molding	.001 kg	1
6	O-ring for sprayer	Sealing	Rubber	Molding	.001 kg	1
7	Rotating sprayer arm	Control water spray	Plastic	Injection molding	.1 kg	1
8	Mesh trap	Collect food particulate	Metal/Steel	Punched	.1 kg	1
9	Front panel cover	Aesthetic	Plastic	Injection molding	.8 kg	1
10	Panel cover screws (phillips)	Panel attachment	Metal	Molded	.002 kg	11
11	Latch screw and washer	Latch attachment	metal	Punched and molded	.001 kg	2
12	Latch sub-assembly	Lock door to body	Metal	Assembled	.1 kg	1
13	Latch spring	Provide resistance	Metal	Bent	.001 kg	1
14	Hinges	Fixed rotation of door	Metal	Punched	.1 kg	2
15	Hinge screws (2 metal, 1 plastic)	Fix door to hinge	Metal and plastic	Assembled	.005 kg	2
16	Metal door frame	Rigidity for door	Steel	Pressed	.5 kg	1
17	Rubber seal/spacer	Prevent water leakage	Rubber	Cut	.005 kg	1
18	Inner plastic door cover	Primary seal for water	Plastic	Injection molding	.6 kg	1
19	Inner door cover screws	Attachment of inner door cover	Plastic	Assembled	.005 kg	2
20	Electric panel to frame screws	Attachment	Metal	Assembled	.005 kg	2
21	Electronics housing	Protect against water damaged	Plastic	Injection molding	.1 kg	1
22	Electric housing connection screws	Attachment	Metal	Assembled	.005 kg	6
23	ON/OFF Button sub-assembly	Activate power to device	Various	Assembled	.05 kg	1
24	ON/OFF Button screws	Button attachment	Metal	Assembled	.005 kg	1	See previous
25	Hinge sub-assembly	Attach door to body	Metal	Assembled	.1	1
26	Plastic chamber rails	Connection of main chamber halves	Plastic	Injection molding	.05 kg	2
27	Chamber rail screws	Attachment	Metal	Assembled	.005 kg	4	See previous
28	Back panel screws	Attachment	Metal	Assembled	.005 kg	10
29	Cord holder	Cord management	Plastic	Cut	.005 kg	1
30	Back Panel	Protection	Metal	Stamped	.8 kg	1
31	Main Body	Protection	Metal	Bent and cut	3 kg	1
32	Main Body Screws	Attachment	Metal	Assembled	.005 kg	8
33	Switch Latch Electronic sub-Assembly	Acknowledge door closure	Various	Assembled	.05 kg	1
34	Inlet tube	Provide feed water	Rubber	Cut	.25 kg	1
35	Rubber feet	Stabilization	Plastic	Injection molding	.01 kg	4
36	Inlet valve sub-assembly	Control water flow rate	Various	Assembled	.1 kg	1
37	Solenoid screw	Inlet control	Metal	Assembled	.005 kg	1
38	Rubber door seal	Prevent water leakage	Plastic	Cut	.001 kg	1
39	Inner shell, upper half	Main washing chamber	Plastic	Injection molding	1.75 kg	1
40	Inner shell seals	Prevent water leakage	Plastic	Cut	.001 kg	1
41	Hose clamp for outlet tube	Attachment	Metal	Bent	.05 kg	1
42	O-ring for outlet tube	Seal	Rubber	Cut	.005 kg	1
43	Outlet hose	Water discharge	Plastic	Injection molding	.15 kg	1
44	Metal base to lower plastic chamber screws	Attachment	Metal	Assembled	.005 kg	6
45	Main plastic housing screws	Attachment	Metal	Assembled	.005 kg	8?
46	Basin to base plates	Reenforcement	Metal	Assembled	.2 kg	2
47	Bottom sub-assembly	Various electrical and mechanical components	Various	Assembled	1.7 kg	1
48	Brick	Balance	Ceramic	Molded	3.25 kg	1
49	Pump hose	Pump connection	Plastic	Cut	.15 kg	1
50	Pump hose clamp	Sealing	Metal	Bent	.05 kg	1
51	Pump hose screws	Attachment	Metal	Assembled	.005 kg	1
52	Main pump sub-assembly	Water intake	Various	Assembled	2 kg	1
53	Sprayer mount	Water feeding and rotation	Plastic	Injection Molding	.025 kg	1
54	Pump turbine sub-assembly	Produce water flow	Various	Assembled	.1 kg	1
55	Thermocouple 1 sub-assembly	Temperature measurement	Various	Assembled	.025 kg	1
56	Heating element attachment	Attachment	Metal	Assembled	.025 kg	1
57	Thermocouple 2 sub-assembly	Temperature measurement	Various	Assembled	.001 kg	1
58	Thermocouple 2 housing	Protection	Metal	Stamped	.001 kg	1
59	Trap to outlet hose	Water discharge	Rubber	Cut	.1 kg	1
60	Heating element sub-assembly	Heat water	Various	Assembled	.2 kg	1
61	Waste pump	Water flow for discharge	Various	Assembled	.6 kg	1
62	Waste to outlet hose	Waste water discharge	Rubber	Assembled	.15 kg	1
63	Circuit board	Washer Control	Fiberglass	Assembled	.15 kg	1
63	Bob casing	Housing/protection	Plastic	Injection molding	.005 kg	1
64	Bob sub-assembly	Water level control	Various	Assembled	.025 kg	1