PokaYoke

1
Poka-Yoke

• CSABA VARGA
• GERGELY THIER
• JUAN PABLO LUNA TORRES

2
Outline

• History
• What is Poka-Yoke?
• Characteristics
• Types of Poka Yokes
• Industrial Applications
• Inspection Techniques
• Cost of quality
• Everyday Examples

3
History

• Poka-yoke (pronounced "POH-kah YOH-kay") was
  invented by Shigeo Shingo in the 1960s.
• The term "poka-yoke" comes from the Japanese
  words "poka" (inadvertent mistake) and "yoke"
  (prevent).

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What is Poka-Yoke?

• A poka-yoke device is any mechanism that either
  prevents a mistake from being made or makes the
  mistake obvious at a glance.
• As Shingo writes, "The causes of defects lie in
  worker errors, and defects are the results of
  neglecting those errors. It follows that mistakes
  will not turn into defects if worker errors are
  discovered and eliminated beforehand Shingo
  1986, p.50.

5
Characteristics

• they are simple and cheap.
• they are part of the process.
• they are placed close to where the mistakes occur.

6
Types of Poka Yokes

• prevention.
• engineers the process so that it is impossible to
  make a mistake.
• remove the need of correction.
• detection.
• signals the user when a mistake has been made.
• they do not enforce the correction.

7
Industrial Applications

• Yamada Electric
• General Motors
• Software Quality

8
Inspection Techniques

• judgment inspection.
• sorting the defects out
• informative inspection.
• Successive checks
• Self-checks
• source inspection.
• before the fact

9
Cost Of Quality

• Cost of achieving good quality
• Prevention
• Appraisal
• Cost of poor quality
• Internal failure costs
• External failure costs

10
Everyday Examples
3.5 inch diskettes cannot be inserted unless
diskette is oriented correctly. This is as far
as a disk can be inserted upside-down. The
beveled corner of the diskette along with the
fact that the diskette is not square, prohibit
incorrect orientation.
Fueling area of car has three error-proofing
devices 1. insert keeps leaded-fuel nozzle
from being inserted 2. tether does not allow
loss of gas cap 3. gas cap has ratchet to
signal proper tightness and prevent
overtightening.
New lawn mowers are required to have a safety bar
on the handle that must be pulled back in order
to start the engine. If you let go of the safety
bar, the mower blade stops in 3 seconds or less.
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Kiitos paljon!

• conclusion.
• comments