J

Jidoka

The ability of machines, operators and processes to detect abnormalities and stop work. This immediately calls attention to the error, stops defective work from continuing, and builds quality in at each process. Jidoka is one of the two pillars of the Toyota Production System along with just-in-time.

Jidoka also known as autonomation, because processes work autonomously without the need for people to monitor them. This requires processes to have "intelligent automation" or the ability to distinguish good output from bad. This frees operators to become multi-process handlers.

The concept of jidoka originated in the early 1900s when Toyota founder Sakichi Toyoda invented an automatic loom that stopped when a thread broke. This freed people from monitoring the looms to catch breaking threads, and one person could run many machines.

Jishuken

A brief, hands-on improvement workshop led typically by and for managers. A jishuken topic can continue for weeks or months through a series of workshops. several months. The jishuken format was a common method to teach TPS to Toyota suppliers. A similar format the five-day kaizen event common in the West.The term means "autonomous research" or "self-study" in Japanese.

Jikoutei kanketsu

See JKK

JKK

Short for jikoutei kanketsu or "Own Process Completion". Each employee considers the next process step to be their internal customer and safeguards quality by checking their own work and never handing off defective information, product or work.

Job Elements Sheet

A document using a combination of words and pictures to define all elements for a specific operation, including steps, time, key points and reasons for key points. The Job Element Sheet documents not just a single step but a complete a set of actions required to advance a process to the next operation. Job Element Sheets are used for training and as a standard work document that is part of the area leader's visual management.

Job Instruction

A four step method for supervisors and experienced workers to teach people how to do work with safely, productively, with reduced defects, less scrap or rework. Abbreviated JI, Job Instruction is one of the J-programs of Training Within Industry, or TWI.

See also Training Within Industry

Job Methods

A four step method for supervisors and experienced workers to teach people how to improve processes by making best use of people, machines, and materials to increase the output of good product in less time. Abbreviated JM, Job Methods is one of the J-programs of Training Within Industry, or TWI.

See also Training Within Industry

Job Relations

A four step method for supervisors and experienced workers to teach people how to handle human relations problems fairly and effectively by gathering the facts, weighing the facts, making a decision, taking action, and checking results. Abbreviated JR, Job Relations is one of the J-programs of Training Within Industry, or TWI.

See also Training Within Industry

Job Rotation

The practice of periodically rotating people through different tasks. The purpose of job rotation is to prevent fatigue and injury from repetition, promote flexibility through cross-training, offer employees new experiences and growth, increase variety and reduce job boredom. The frequency of rotation depends on the repetitiveness and difficulty of tasks, as well a how critical it is to develop cross-training for the task.

Job Safety

A four step method for supervisors and experienced workers to teach people how to identify and eliminate potential safety hazards in the workplace. Abbreviated JS, Job Safety is a more recent addition to Training Within Industry, or TWI.

See also Training Within Industry

Just-in-time

Abbreviated JIT, it is a system to deliver only what is needed, when it is needed, in the amount needed by the customer. JIT is comprised of three elements:

  1. takt time
  2. one-piece flow
  3. the downstream pull system

JIT relies on heijunka, or a leveled load and averaged product mix, as a foundation. JIT and jidoka are the two pillars of the Toyota Production System.

Achieving just-in-time requires removing many obstacles to flow, pull and small lot production. The pursuit of JIT leads to elimination of various wastes in order to achieve the best performance in quality, low cost and the shortest lead times.