The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 16, 1989
Filed:
Apr. 29, 1988
Applicant:
Inventors:
Akira Okazaki, Matsudo, JP;
Hiroshi Minami, Matsudo, JP;
Assignee:
Mabuchi Motor Co., Ltd., , JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H02P / ;
U.S. Cl.
CPC ...
388815 ; 388824 ; 388902 ; 388930 ; 388934 ; 388935 ;
Abstract
A speed control device for d-c motors includes an IC control circuit having such a construction that a reference voltage is generated across two of its terminals C and D. Additionally, a current proportional to the armature current of the d-c motor is kept flowing in the terminal D at all times. A transistor is connected across the terminals C and D of the control circuit so that motor revolution can be changed linearly by means of a variable resistor connected in parallel across the base and collector of the transistor. With this arrangement, the revolution of d-c motors can be accurately controlled.