July 2010 Archives

The LCA project's success or failure is largely determined by the result of design process of conceptualizing to creating the manufacturing drawings. To "Design" is for the designer to create all the necessary information (LCA performance, manufacturing drawings, operation instruction information) of the LCA project to be built. A flow of design to LCA completion is as [Fig.1] below.

[Table.1] Relationship of LCA design and LCA cost reduction

The LCA design process begins with a conceptualizing of functions with illustrations, then proceeds to design drawing and manufacturing drawing creations. To this point is a process of turning the abstract ideas into drawing information.
After the drawings are created, parts are manufactured and purchased components are procured according to the drawings, then on to assembly work and programming. All of these steps are executed according to the contents of the design. Therefore, it can be said that a good LCA depends on a good design.
A manufacturing system including LCAs are composed of purchased parts such as screws and springs, purchased machine elements such as motors, etc., and machined components made of raw materials (including control programs). Cost reduction ideas for each, as well as assembly/maintenance cost reduction ideas can be summarized in a table above. It can also be seen from this table that the quality of design largely affects the success rate of LCA.

Let us take a look at the aspect of LCA designs in regard to "Wide Variety Small Volume" production lines.

We'll begin with sorting of the design process and a flow. [see Fig. 1] "Designing" is a process of decision making (on LCA performance, manufacturing drawings, and information on how to operate) to create "Something" when a need to materialize such "Something" arises. If the design process is commenced forward without giving the proper thoughts, separate design drawings would be need for every production item and the amount of work required will increase exponentially. In actuality, businesses are offering wider variety of products.

For this diversifying needs, there is a design approach called VR (Variety Reduction)

[Table] VR Design Approach

In order to execute effective LCA, the concept of "Good Designs" needs to be first understood, before a good plan can be constructed.

Let us think about "Good LCA Designs"
The closest critics on any LCA machines or jigs are the operators who use the manufacturing systems on factory floors. Therefore, the most sought aptitude for an LCA Designer would be an ability to present "good" suggestions or proposals to those operators. Such aptitude would be backed up by the following.

	1.	Adequate product knowledge
	2.	Complete understanding on manufacturing processes and operation details
	3.	Ability to understand product cost structure
	4.	Sufficient knowledge (or understanding) on relevant manufacturing technology

The meaning of a word "Good" has revolved and evolved over the years as the industrial era phases have. Since the twilight time of the industrial automation age, a unit of measurement for the success has been a Corporate Principle driven return on investment, or cost vs. performance. But in recent times, socioecological parameters (i.e. effects on industrial waste management costs) are also being included. A prominent example of the above is Life Cycle Cost (LCC: see Notes-1).

Therefore, the LCA designer must devise effective designs taking in consideration the needs of the surrounding operators as well the socioecological factors. The functional keywords in "Good"LCA can be consummated as below.

Dimension specification for the three parts related to assembly accuracy previously identified in #047 is explained.

(1) Meaning of "matching the assembly datum of the parts"...

(2) Method of dimension specifying for each part. (see [Fig.1] and [Fig.2])

By designing with dimension specifying datum surfaces on all parts to be coincided, post assembly accuracy can be assured. This design scheme utilizes three parts each with datum surface A, A', and A" to assure the assembly accuracy of X axis and Y axis.

In order to benefit from this dimensioning specification methods to realize low cost (can be assembles without highly trained labor) machines, the designer is required of the following.

	1.	Able to understand the assembly process.
	2.	Knows how the parts are machined.
	3.	Able to properly: specify dimensions, specify tolerances, specify part fitting.