Ice cream maker
From DDL Wiki
Component List
Failure Mode and Effects Analysis
This chart shows the top failure modes of the ice cream/sorbet maker. This is a risk assessment of the major parts of the device and how each failure ranks on a priority list. The failures are recorded in a few categories, which are severity, occurrence, and detection. The severity of the failure is a value that represents how crucial this part or action is to the usage of the product. The occurrence represents how often the failure occurs per 10,000 products. The detection represents how easily the failure mode can be detected, either in the assembly line process or by the user. Here is our FMEA of our ice cream maker. After the table, some of the values will be explained in further detail.
Item & Function | Failure Mode | Effects of Failure | S | Causes of Failure | O | Design Controls | D | RPN | Recommended Actions | Responsibility & Deadline | Actions Taken | S* | O* | D* | RPN* |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Motor
| Electrical failures: Motor may overheat and fail | Product will not mix the ice cream, and the product may not have good consistency. | 8 | Motor may overheat when the ice cream starts solidifying. The increased viscosity of the ice cream may add too much torque on the motor. | 6 | Testing with different types of ice cream and find the point when the load applied is too high | 3 | 124 | Find a controller that will turn off the motor once the torque applied to the motor gets too high | Motor Manufacturer | Integrate a current sensor into the design | 8 | 1 | 3 | 24 |
Mechanical Failure: Gear train may strip | The rotation of the motor will not be transferred to the product | 8 | The increased friction in between the separate gears can cause the gears to strip | 2 | Testing the durability of the gears | 3 | 48 | Test different materials to find the most cost-effective solution | Gear Manufacturer | N/A | 8 | 2 | 3 | 48 | |
Mixing Arm
| Mixing arm breaks/fails | Contents of the bowl will not be properly mixed to form a consistent product. | 4 | The increased viscosity of the product may cause the mixing arm to break. | 3 | Test to see the breaking point of the mixing arm. | 1 | 12 | Test different materials to find the most cost-effective solution | Manufacturer | N/A | 4 | 3 | 1 | 12 |
Wiring
| Current does not get transferred from the power outlet to the motor | Motor will not rotate the bowl, so contents of bowl will not get mixed. | 4 | The increased viscosity of the product may cause the mixing arm to break. | 2 | Before final assembly of the product, test connection points to see if all wiring points are valid | 3 | 24 | Install a station in the assembly process to make sure that all wiring connections are good | Assemblerer | N/A | 4 | 2 | 3 | 24
|
Switch
| Switch does not allow current to pass through | Motor will not rotate the bowl, so contents of bowl will not get mixed. | 4 | The switch connection may not contact the part that is used to close the circuit | 2 | Test to see if connection points are durable after many clicks (turn on and off many times) | 3 | 24 | Test a switch for 1,000 times to see if the switch operates properly each time | Assemblerer | N/A | 4 | 2 | 3 | 24 |