Overheat preventing device for motor vehicle engine

• US 3,894,521 A
• Filed: 12/04/1973
• Issued: 07/15/1975
• Est. Priority Date: 12/05/1972
• Status: Expired due to Term

• Current Assignee: Hiroshi Sakasegawa, Yoichi Yamamoto
• Original Assignee: Hiroshi Sakasegawa, Yoichi Yamamoto
• Inventors: Sakasegawa, Hiroshi, Yamamoto, Yoichi
• Primary Examiner(s): Antonakas, Manuel A.
• Assistant Examiner(s): O'Connor, Daniel J.
• Application Number:
  US05/421,618
• Time in Patent Office: 588 Days
• Field of Search: 123/41.11,41.12,41.49,41.01
• US Class Current: 123/41.12
• CPC Class Codes: F01P 2001/005 Cooling engine rooms
• CPC Class Codes: F01P 2005/046 with electrical pump drive
• CPC Class Codes: F01P 2031/30 Cooling after the engine is stopped
• CPC Class Codes: F01P 2060/14 Condenser
• CPC Class Codes: F01P 5/04 Pump-driving arrangements
• CPC Class Codes: F01P 5/12 Pump-driving arrangements
• CPC Class Codes: F01P 7/042 using fluid couplings couplings or clutches of this type per se F16D35/00
• CPC Class Codes: F01P 7/048 using electrical drives
• CPC Class Codes: F01P 7/08 by cutting in or out of pumps

Abstract

A motor vehicle engine provided with a radiator and a fan driven by the engine to cool the radiator, and an electric motor operatively connected to the fan through a one-way clutch to rotate the fan independently of the engine rotation and a control circuit of the electric motor, the electric motor being actuated when the engine speed is so low that the fan is not rotated at a speed to supply enough air for cooling the radiator satisfactorily.

Claims

1. An overheat preventing device in a motor vehicle having an engine, a radiator through which a pump circulates engine coolant, a condenser for an air conditioner comprising;

a fan;

a one-way clutch;

a first pulley on a shaft supported by the engine and engeable with said fan through said one-way clutch; and

fan being normally rotated from the engine shaft through said one-way clutch, when engaged, and a first V-velt means to air cool the contents of the radiator and the condenser;

an electric motor with a motor shaft;

a second pulley mounted freely rotatably on said motor shaft;

a third pulley fixedly mounted on said fan;

a clutch means fixedly mounted on said motor shaft and engageable with said second pulley for said second pulley to be rotatable with said motor shaft;

said fan being rotatable by said electric motor through said second pulley when engaged by said clutch, a second V-belt and said third pulley;

an ignition switch and a first control switch means connected in series between said motor and a battery, said first control switch means closing to energize said motor when one of the temperature in said radiator, the temperature and pressure in said condenser reaches a predetermined value and the vehicle speed decreases below a predetermined value;

a second control switch means, a delay switch and a thermosensitive switch also connected in series between said motor and the battery and in parallel with said ignition switch and said first control switch means being closed when said ignition switch is opened, and said thermosensitive switch closing only when the ambient temperature is above a predetermined level to energize said motor for a predetermined period through said delay switch and said second control switch means when said ignition switch is open.

2. A device as claimed in claim 1, wherein said one-way clutch is a fluid coupling comprising an impeller operatively cOnnected to said engine shaft through said first pulley, a runner connected to said fan and slidably mounted on said first pulley shaft, and wherein said clutch is an electromagnetic clutch means having a magnetic coil mounted in said electric motor for electromagnetically coupling said second pulley and said motor when energized by said battery to drive said fan when one of the temperature of said radiator, the pressure and temperature of said condenser reaches a predetermined value and vehicle speed decreases to a predetermined value.

3. A device as claimed in claim 1, wherein said one-way clutch and said clutch are of spring type, said one-way clutch having its drive portion operable by said engine shaft, a helical spring fixed at its one end to said drive portion and its other end forming a one-way connection with said third pulley;

said clutch having its drive portion fixed to said motor shaft, a helical spring fixed at its one end to said drive portion and its other end frictionally driving said second pulley.