| 摘要 |
1,214,909. Indicating electric motor speeds. GENERAL ELECTRIC CO. 26 March, 1968 [27 April, 1967], No. 14454/68. Heading H2A. In an air-cooled electric motor 10 comprising a field stator and a housing 12 having mounted at one end a first end shield 22 which includes a bearing rotatably supporting the shaft 30 of a wound armature assembly 26 having a commutator 28, there is provided a shaft speed indicating assembly comprising a corer member 98 mounted externally on the end shield and enclosing an end of the shaft and carrying a light source 58 adjacent an optical disc 52 having a circular track mounted for rotation with the shaft end, together with a light responsive means eg. a photo-cell 54 mounted on the end shield adjacent the disc and which produces a signal in response to energy received through the disc from the light source. The cover member forms a substantially air-tight dust-free enclosure for the indicating assembly, and is encompassed by an enclosure member 106 mounting terminal boards 114, 116 and having holes 112 through which cooling air is drawn by an exhaust fan 34, deflectors 48 being provided to guide the air on to the commutator 28, brushes 31 and armature assembly 26. Although shown as a D.C. motor it may alternatively be of the A.C. type or have a permanent magnet field. |
