1. Matt Manning
March 15, 2008
TOYOTA PRODUCTION SYSTEM
INTRODUCTION
The Toyota Production System is a system of nested experiments through which operations are
constantly improved.i
Many of the tools that have been developed as a result of the Toyota production system
have proven to be quite valuable across multiple functions. However, kanbans, lean
manufacturing, and continuous improvement came about as responses to even more simple
questions regarding the manufacturing system. These questions should lead to how the process
could be designed more efficiently to eliminate waste.
Before one begins to implement changes, derived from the Toyota production system,
into its own manufacturing system you must differentiate whether you are trying to implement
the tools used by Toyota or the principles upon which those tools are based. Many companies
have tried and failed to implement the tools establish at Toyota. These failures may be due to
not fully understanding their own business process and which problems they were trying to
address.
LEAN PRODUCTION
Lean production has been defined as “a productive system whose focus is on optimizing
processes through the philosophy of continual improvement” (Pg. 87). The idea with lean
production is to waste as little time, effort, and resources as possible. Value-added functions are
2. to be maximized, then evaluated and maximized again. Toyota focused in decreasing waste in
the following seven areas:
1. Overproduction
2. Waiting
3. Transportation
4. Processing itself
5. Stocks
6. Motion
7. Making defective products
JUST IN TIME (JIT)
As Toyota representatives toured Ford manufacturing plants in Michigan, they were not
impressed by the huge inventory levels that were used to smooth production lines that were
largely variable. Much more impressive to the delegation was the simple replacement system
used by a supermarket. Since many supermarket foods have such a short shelf-life, these items
are only replaced once purchased. This eliminated the need for huge stockpiles and the
infrastructure to store them.
As JIT is applied to the manufacturing process, one must keep strict attention on any
possible delays. First, these delays will prove to be ever most costly due to the complete
interdependence of the system. Second, these delays will highlight the next step to take in the
continuous improvement process.
KANBANS
The use of kanbans helped Toyota to better implement the JIT system. Kanban is a
visual signaling system used to trigger action. The visibility makes it easy to know when to
3. “pull” an item to the next station. Pros of kanbans include: reducing excessive movement and
reducing excessive production.
CONTINUOUS IMPROVEMENT
Improvement methods at Toyota have a number of unique characteristics. First, proposed
improvements are structured as experiments. This allows for statistical date to prove whether a
proposal will be beneficial or not. Also, this allows for employee involvement in the
improvement method. As employees are part of the process, they can better observe first-hand
how individually beneficial process improvements are. Finally, a unique worker-manager
relationship is established where both are actively involved in the process.
WHERE THE TOYOTA PRODUCTION SYSTEM IS USED
Toyota has felt no shame in sharing its secrets with the rest of the world. The process of
implementation took Toyota more than two decades. A number of executives have actually
toured the manufacturing facilities throughout the Toyota network. Much like within the
company itself, visitors are not told directly what improvements to be implemented. We are to
learn through observation and allow the process to show us the failures. Based on these
observations, improvements may be proposed.
Other Resources
Many books and articles have been written regarding the Toyota Production System. The
reliability of such sources has come into question. I suggest those resources from persons who
were directly involved in the development process such as Taiichi Ohno and Shiego Shingo.
4. Articles
“Learning to Lead at Toyota,” Spear, Steven J. Harvard Business Review, May2004, Vol. 82
Issue 5, p78-86
“Decoding the DNA of the Toyota Production System”, Spear, Steven; Bowen, H. Kent. Harvard
Business Review, Sep/Oct99, Vol. 77 Issue 5, p96-106
Books
Study of the Toyota Production System: From an Industrial Engineering Viewpoint, Shigeo
Shingo
Toyota Production System, Taiichi Ohno
The Toyota Way, Jeffrey Liker
i
Learning to Lead at Toyota. By: Spear, Steven J.. Harvard Business Review, May2004, Vol. 82
Issue 5, p78-86