This inventor holds 3 USPTO granted patents. Top assignees: Yazaki Corporation, Koito Manufacturing., Ltd., Toyota Jidosha Kabushiki Kaisha. Active years: 2011-2026.
Location History:
- Shizuoka, JP (2011)
- Makinohara, JP (2013)
Company Filing History:
2 out of 8,358 
1 out of 39 
1 out of 38,723 
Years Active: 2011-2026
Title: Shigemi Ishima: Innovator in Overcurrent Protection and Power Supply Control
Introduction
Shigemi Ishima is a notable inventor based in Shizuoka, Japan. She has made significant contributions to the field of electrical engineering, particularly in overcurrent protection devices and power supply control systems. With a total of 3 patents, her work has had a meaningful impact on the industry.
Latest Patents
Ishima's latest patents include an overcurrent protection device and an overcurrent protection system. The overcurrent protection device is designed to provide time differences among the timings for executing retry operations among multiple overcurrent protection devices connected to a common power supply. This innovation ensures that when a battery voltage (VBA) falls below a threshold voltage after an FET (Q) of an IC circuit is activated, all FETs (Q) of the respective IC circuits are turned off. The system clocks the time until the battery voltage reduces to a value lower than the threshold voltage after the FET (Q) is turned on. If this time is less than 400 microseconds, the count value N is incremented. The FETs (Q) are then turned on again after a randomly set standby time (Tp). When the count value N reaches 7, the FET (Q) of the IC circuit is held in the turned-off state, allowing only the load-driving circuit experiencing a dead short to be stopped while continuing the operation of other load-driving circuits.
Her power supply control apparatus is another significant invention. It connects a ground to a suitable electric potential when the ground is disconnected. This apparatus includes a control circuit with a switch element and a switch control unit, along with a load. One terminal of the load is connected to a direct-current power supply through the switch element, while the other terminal connects to a ground electric potential. The switch control unit outputs a ground current flowing toward the ground electric potential. The control circuit features a bypass device that allows the ground current to pass through the load when the connection between the ground terminal and the ground electric potential is interrupted. This innovation ensures stable operation of the switch control unit when the ground current flows.
Career Highlights
Throughout her career, Shigemi Ishima has worked with prominent companies such as Yazaki Corporation and Toyota Motor Corporation. Her experience in these organizations has contributed to her expertise in electrical engineering and innovation.