Group 26 - Mr. Coffee Coffee Maker Gate 4 Product Explanation
A predetermined difficulty scale was used for the reassembly process. As noted from the previous disection process, a very complex rating scale is not needed due to the simplicity of the coffee maker's design. From this conclusion a revised rating system has been used for the reassembly. The scale has three levels, 1-Easy, 2-Medium, 3-Hard. The levels differentiate on time required, and simplicity of task.
1 - Easy. Minimal effort. Short time required per task.
2 - Moderate. Average effort. Short to medium length of time required per task.
3 - Hard. Maximum effort. Long time required per task
The table listed below provides a detailed description of each step in the reassembly process, along with a photograph, the approximate time requried, and difficulty rating for the process. For the entire disection, the only tool required will be a #1 Phillips Head Screw driver.
For an enlargment of a desired photograph simply click on the image provided in the table.
|Step number||Description of Step||Tools Required||Time Required||Dificulty Rating||Picture|
|1||Start by assembling the switch pin by hand.||Hand||0:55||1|
|2||Insert the switch pin then screw in the two 7/16” Pan Machine Screws which are located at the electrical switch.||#1 Phillips Head Screw Driver||0:30||1|
|3||The assembley of the water intake valve can now be done. It is reassemble by placing the spring into the bottom black piece, followed by the top black piece, and then slipping the small rubber ring around the top black piece to secure it.||Hands||0:15||1|
|4||Insert the water intake valve by pushing it through the large rubber sealing ring on the reverse side.||Hands||0:10||1|
|5||Reattached the red tube holder to the base by screwing the four ½” Pan Machine Screws into the base and the holder from which they were removed from.||#1 Phillips Head Screw Driver||1:30||2|
|6||The motor can now be put back in by sliding the casing column in the motor reservoir.||Hands||0:30||1|
|7||Screw the four ¾” Pan Machine Screws into the square motor casing column and its base.||#1 Phillips Head Screw Driver||1:45||2|
|8||Connect the red and mauve wires to the circuit board by hand.||Hands||0:30||1|
|9||The opposing end to the 11.5in red tube can now be attached to the heating coil. It then reconnected to the motor base.||Hands||0:30||1|
|10||With the coffee maker being in half it allows access to the two scre holes located on the wall perpendicular to the heating base, screw in the two #5 5/8 Pan Machine Screws removed previously from the system to secure the motor to the casing of the cofffee maker.||#1 Phillips Head Screw Driver||2:00||2|
|11||The 5.5in red tube is then attached to the heating coil and is completely attached to the system by pushing it towards the base.||Hands||0:25||1|
|12||To further secure the motor in its place, two 3/16 Zinc Plated Pan Machine Screws right and left of the power cord slot are screwed into the coffee maker. This permately reattaches the two halfs of the coffee maker||#1 Phillips Head Screw Driver||1:45||2|
|13||Attach the circuit board base by screwing in a 5/16” Pan Machine Screw located in the center of the circuit board.||#1 Phillips Head Screw Driver||0:15||1|
|14||To attach the main circuit board base you must first assemble the coffee maker wall by screwing in two 3/16 Zinc Plated Pan Machine Screws located in the gap between the circuit board and the coffee maker wall.||#1 Phillips Head Screw Driver||2:30||3|
|15||Attach the plastic wire guard by using two #2 1/2 Zinc Plated Pan Tapping Screws, to the internal wires of the coffee maker.||#1 Phillips Head Screw Driver||0:20||1|
|16||The heating plate can now be attached by hand by dropping it into the system as shown in the picture.||Hand||0:10||1|
|17||The clear plastic display window can be attached by using two #1 1/18 Flat Machine Screws.||#1 Phillips Head Screw Driver||0:45||2|
|18||Four 3/16” Pan Machine Screws can now be attached to the back of the control panel board to attach it to the rest of the system.||#1 Phillips Head Screw Driver||0:55||1|
|19||The opposite end of the wire plug can now be attached to the control center board by hand.||Hands||0:10||1|
|20||Two ¼” Pan Machine Screws can be screwed into the control center base. The control center is now attached to the rest of the system.||#1 Phillips Head Screw Driver||0:30||1|
|21||Attach the control center to the main circuit board by attaching the wire plug to the main circuit board.||Hands||0:20||1|
|21||The red tubes can now be attached to the heating coil by hand. The heating coil should be placed in its proper position where it fits in the system.||Hands||0:25||1|
|22||The metal is guard attached over the heating coil by screwing in two 5/8” Pan Machine Screws.||#1 Phillips Head Screw Driver||0:30||1|
|23||The Base is then attached to the coffee maker by hand.||Hands||0:20||1|
|24||The two front and back holes are used to screw in #4 5/16” Tapping Screws to secure the base to the coffee maker.||#1 Phillips Head Screw Driver||1:00||1|
|25||Two rubber stops are placed over the two front holes of the screws attached to the bottom of the base.||Hands||0:10||1|
|26||All internal components should be inside the coffee maker and the coffee maker base should be secure to the system. The coffee maker can now be flipped over by hand.||Hands||0:05||1|
|27||The rubber stopper inside of the coffee basket can now be attached to keep the spring assembly intact. The spring assembly components when attached to the basket should easily slide into one another.||Hands||0:05||1|
|28||The Coffee Basket followed by the Filter basket can now be place into the coffee maker by hand.||Hands||0:10||1|
|29||To assemble the grinder a 5/16” Pan Machine screw is screwed into the grinder assembly to attach to the water channel to it.||#1 Phillips Head Screw Driver||0:20||1|
|30||Using a 9/16” Pan Machine Screw the black plastic half circle shape piece is attached to the bottom of the grinder.||#1 Phillips Head Screw Driver||0:20||1|
|31||The grinder lid is attached to the top of the grinder by hand to complete the grinder assembly .||Hands||0:10||1|
|32||The grinder assembly and grinder lid is placed into the coffee maker by hand.||Hands||0:05||1|
|33||The coffee maker flip down lid can now be attached by sliding it into the hinges.||Hands||0:10||1|
|34||The coffee maker reassembly is now complete.|
Analysis of Reassembly Process
The reassembly process was about the same as the disection process. The process took 19 minutes and 40 seconds, slightly shorter than the 20 minutes it took for the dissection process. The redisigned difficutly scale proven to give a better discription of the effort and time required relative to the task. One point to note, is that even though the scale is partially based on time, it is based on time relative to the task. Meaning that even though step 18 took 55 seconds and step 29 took 20 seconds, they still recieved the same difficulty rating since step 18 required the same amount of effort but was a longer process. Adversely, step 14, which recieved the only 3-Hard rating for the reassembly, was due to the time required to get the screws to line up with their designated holes that were not visible by any viewing angle, not because the actual task of screwing the screws into the holes required a significant amount of effort.
Analysis of Original Assembly
The coffee maker was orignally assembled to not be brokedown as far as the design process in Gate 2. The sodered connections from the motor to the circuit board suggest that the manufactures did not the consumer tampering with the motor. The different screws were mostly likely used from easy automation assembly in the early steps. Due to its small size and simplicity of the deivce it is assumed that all components are made and assembled in the same manufactoring plant.
The Mr. Coffee coffee maker has a few major problems with it. Consumer reviews about the Mr. Coffee model GBX25 12-cup brewer state that the brew quality is very poor for this model. Most reviews state that the main problems with the coffee maker was that the grinder does not grind the beans well enough, the filter does not filter the coffee properly, and the brew speed is not slow to achieve the desired brew stregth. The design revisions that follow address these problems addressed by the consumer reviews. Each revision provides a purposed solution to the designated problem as well as the affects that will occur on the four factors (social, economic, environmental, global) as a result of the design revisions.
The Coffee Bean Grinder
The biggest influence on the quality of the coffee brewed by the coffee maker is the grinder. Most of the flavor and strength of the coffee is dependent on the quality of the grounds and this is determined by the grinder. The model GBX25 has a poor quality grinder, and most consumer reviews complain about the grinder not grinding all of the beans and not grinding the grounds to a fine enough size.
In order to fix this problem with the coffee maker, it is proposed two modifications to the grinder. The first was to make more blades then just the two, make them sharper, and make them out of a better and more resilient material. The proposal for this change was to make a four blade grinder with two levels of blades which would reach more of the beans. the second part of this change would be to make the blades out of a higher grade of steel. The blades in the coffee maker are currently made of an AUS-8 stainless steel. VG-10 steel is harder and holds a sharper edge longer, but it is also more costly to make.
The second part of this change would be to make the grinder more powerful. This would include making a stronger motor for the grinder however, and this would drastically change the product in many ways. The coffee maker would have to be larger, have different circuitry and power input, and be reshaped to fit a larger motor. This change would increase the cost of production as well as increase the quality of the brew.
The Impact of the Change and the Four Factors
- The overall changes to the grinder subsystem in the model GBX25 would result in a much better brew quality. This is a large societal factor and it would boost sale volume if people in society were getting a better quality coffee.
- These changes would also result in a significant increase in cost, which is a negative economic impact. This would drive some potential consumers away.
- The environmental factor does not play a large enough role in this decision to influence it to much. A slightly higher power usage for the product would be the most significant in this category.
- Global factors would not change much with these changes. Coffee quality and cost are mostly universal for the regions that sell this model. People want good coffee at the lowest price possible.
It is concluded that the increase in cost would balance out with the increase in coffee quality, and this modification would be feasible. This does not seem to be the most ideal change however, as the changes to the product would be drastic.
The Coffee Filter
The second most influential factor in the quality and strength of the coffee brewed is the filter system. The filtration system in the model GBX25 is currently a simple basket/screen system that works relatively well if all that the consumer is concerned with is not getting grounds in their coffee. The problem is that the filter system is not of a high enough quality to produce a strong coffee. This is because the simple screen and basket method does not allow for a full mixing of the water with all of the grounds.
In order to fix this problem, a different filtration system could be implemented. A better system would be a slow-brew filter that has a paper filter that you change out after use. This filter forces the water to stay and mix with the grounds for a longer time. This in turn would increase the strength of the coffee that is brewed with no change to the grounds.
Implementing this change would result in needing a larger filter area within the filter subsystem. This could be done simply by extending the top of the coffee maker. This change would increase the material needed however, and thus increase the cost of production. This would also slow down the brew speed slightly and when it comes to coffee, speed is often important.
The Impact of the Change and the Four Factors
- The global concerns for this change are minimal. The regions that this coffee maker are sold have essentially the same views on coffee brew speed and cost as well as quality.
- The economic factor plays a role in this change because it would cost more to make the product and therefore cost more to buy the product. This increase in price, although small in comparison to the first change proposal, would still influence the sale of this product.
- The environmental factors for this change are minimal and would not play a large role in the decision making.
- The Societal factor would be the largest part of this change. This modification to the product would have both negative and positive effects on the societal factor. The positive effect would be that the coffee quality and strength would increase, creating a happier consumer. This would help to drive sales and demand up. The negative impact would be that the coffee would brew slower every time, with no setting to speed up the brewing. This would cause people who would sacrifice quality for speed to turn away from this product, driving sales down a bit.
In the end, the benefit to product quality would outweigh the negative impact on time and cost. This means that this design revision would be beneficial to the product, but again, we do not feel that this is the only way, nor the absolute best way to improve the quality.
Slower Brew Speed
After doing some research on what factors play into a coffee brew strength and flavor,it was found that a large contributor to this is the brew time. The longer the water is mixing with the grounds before filtering out through the filter funnel, the bolder the flavor is. This means that a good area to change when the desired result is stronger coffee is the brew time. The Mr. Coffee model GBX25 has a built in setting for brew strength in it. The settings are normal brew and strong brew. The problem is that even the strong setting on the coffee maker is not strong enough for many consumers. Most of the complaints for this model of the Mr. Coffee coffee maker are about the strong setting of brew not being nearly strong enough.
A good change to the Product would be to modify these settings. To do this, it is proposed that more options are added to the strength setting. The more options would include a weak, medium, strong, and extra strong setting list. Each setting would then be modified accordingly. It was found that the mixing time during the brewing process for the normal setting was half that of the strong setting. It was decided that the weak setting would be slightly less than the normal setting was. The normal setting would be slightly increased from the original. The strong setting would also be slightly higher than the original. The extra strong setting would be set to be greater than the strong setting. The following table compares the revised ouputs to the original outputs of the coffee maker.
|Design Modification Comparison|
|Original Product Settings|
|Setting Name||Grounds/Water Mixing Time (seconds)||Coffee Strength/Quality|
|Normal||15||Weak Coffee, Poor Quality|
|Strong||30||Medium coffee strength, average quality|
|Weak||15||Weak Coffee with low quality flavor.|
|Medium||35||Medium strength coffee. Medium quality flavor|
|Strong||45||Strong coffee, good quality flavor|
|Extra Strong||55||Very strong, Bold coffee. Very high quality flavor.|
Due to the fact that the Coffee maker already has a setting system for the strength of brew, making this change would be extremely easy. All that would need to be done to reach this goal would be a minor programming change and a small change to the timing that the coffee grounds mix with the water. The changes would be easy to make overall, and they would not change the actual production of the product much at all.
The Impact of the Change and the Four Factors
- Global Factors do not play much of a role as usual for the coffee maker. The strength and quality increase will be a benefit in all regions.
- Economic Factors are positive in this change. The increase in quality will allow for a higher asking price on the product, thus increasing the profit margin. The changes would not really require much more capital input for production, because there would be no more raw materials, and minimal more programming. This means that this change would be mostly pure profit.
- Societal Factors for this change are also beneficial. More people will want to buy the coffee maker when the quality and strength of the coffee made is higher. The overall sales will increase and people will find the product more appealing.
- Environmental Factors are minimal in this modification, as there is no new material, no change in production, and very minimal change in energy intake and waste.
This change is the most beneficial and profitable to the product. It has the most gain and the least loss when looking at the four factors. Also, this would be a very simple change that would not need to modify the product externally at all. This change is the optimal one for the Mr. Coffee GBX25.