Title:
【発明の名称】過電圧防止装置
Document Type and Number:
Japanese Patent JP3367158
Kind Code:
B2
Abstract:
PURPOSE:To provide a controller of a parallel-connection DC motor which can simultaneously control each rotary speed of a plurality of DC motors which are connected in parallel for a single DC power supply in a safe state without using a high breakdown voltage switching element or a special protection circuit. CONSTITUTION:The controller of a parallel-connection DC motor simultaneously controls each rotary speed of a first DC motor for driving and a second DC motor for loading and unloading which are connected in parallel with a battery in a battery fork lift using periodical first pulse wave P1 and second pulse wave P2. For example, the ratio of the period of the first pulse wave P1 to the second pulse wave P2 is set to an integral multiple, such as 1 and 2, and the generation start delay of the second pulse wave P2 is shifted from the generation start time of the first pulse wave P1 by approximately several mS.
Inventors:
Hiroki Ohta
Application Number:
JP22115093A
Publication Date:
January 14, 2003
Filing Date:
September 06, 1993
Export Citation:
Assignee:
KABUSHIKI KAISHA TOYOTA JIDOSHOKKI
International Classes:
B60L15/28; B66F9/24; H02P5/68; (IPC1-7): H02P7/68; B60L15/28; B66F9/24
Domestic Patent References:
| JP61214707A | ||||
| JP3117393U |
Attorney, Agent or Firm:
Yoshiyuki Ohsuga