초록 ▼

An electronically-controlled viscous fan drive having a one-piece accumulator and reservoir located on the top side of the clutch. The accumulator also has a low pressure and high pressure fill hole for allowing movement of viscous fluid from the reservoir to a anti-bleedback chamber and into the op

An electronically-controlled viscous fan drive having a one-piece accumulator and reservoir located on the top side of the clutch. The accumulator also has a low pressure and high pressure fill hole for allowing movement of viscous fluid from the reservoir to a anti-bleedback chamber and into the operating and working chamber of the coupling during normal operation. A radially balance valve disk having a step up feature coupled to a spring and an actuator electronically controls movement of viscous fluid from the reservoir to the anti-bleedback chamber through the fill holes by energizing or deenergizing the spring based on engine operating conditions. The valve disk may be a one-piece or two-piece design. The accumulator is designed to prevent morning sickness associated with the flow of viscous fluid from the reservoir to the operating chamber during engine off situations.

대표청구항 ▼

1. An electronically controlled viscous fan drive used on an internal combustion engine comprising:an actuator capable of generating a magnetic flux;a housing member;a cover member coupled to said housing member;an actuator shaft coupled to said actuator and partially disposed within said housing me

1. An electronically controlled viscous fan drive used on an internal combustion engine comprising:an actuator capable of generating a magnetic flux;a housing member;a cover member coupled to said housing member;an actuator shaft coupled to said actuator and partially disposed within said housing member and said cover member;an input coupling assembly coupled to said actuator shaft, said input coupling assembly capable of rotating at an input speed;an input coupling member coupled to said input coupling assembly and disposed within said housing member and said cover member, said input coupling member and said cover member defining a working chamber therebetween;an accumulator coupled to said input coupling assembly and sealed to said input coupling member, said accumulator having an inner circular ring and an outer circular ring and a plate portion; said inner circular ring and said outer circular ring defining an anti-bleedback chamber, said anti-bleedback chamber having a pair of outer regions;a fluid reservoir chamber defined by said inner circular ring, said plate portion, and said input coupling member, said fluid reservoir chamber in fluid communication with said working chamber;a pumping element coupled between said working chamber and said fluid reservoir chamber through said cover member;a fluid operating chamber defined by said accumulator, said cover member, and said input coupling member, said fluid operating chamber in fluid communication with said working chamber and each of said pair of outer regions;a low pressure fill hole contained within said inner circular ring, said low pressure fill hole capable of moving a quantity of a viscous fluid from said reservoir chamber to said anti-bleedback chamber;a high pressure fill hole contained within said inner circular ring, said high pressure fill hole capable of moving a quantity of said viscous fluid from said reservoir chamber to said anti-bleedback chamber;a valve disk coupled to said actuator shaft and disposed within said fluid reservoir chamber, said valve disk having an inner step region and an outer step region;an actuator piston coupled around a portion of said actuator shaft, said actuator piston capable of axial move met along the length of said input coupling assembly in response to said magnetic flux to position said valve disk in either an engaged position, a partially engaged position, or in a disengaged position; anda spring coupled to said actuator shaft and to said valve disk such that said spring is between said valve disk and said actuator piston, said spring normally biasing said valve disk in said engaged position in the absence of said magnetic flux of said actuator. 2. The fan drive of claim 1, wherein said accumulator comprises a molded plastic accumulator. 3. The fan drive of claim 1, wherein said engaged position is characterized such that said valve disk is positioned wherein said low pressure fill hole is not covered by said inner step region and wherein said high pressure fill hole is not covered by said outer step region. 4. The fan drive of claim 1, wherein said partially engaged position is characterized such that said low pressure fill hole is not covered by said inner step region and such that said high pressure fill hole is partially covered by said outer step region. 5. The fan drive of claim 1, wherein said partially engaged position is characterized such that said low pressure fill hole is not covered by said inner step region and such that said high pressure fill hole is covered by said outer step region. 6. The fan drive of claim 1, wherein said partially engaged position is characterized such that said low pressure fill hole is partially covered by said inner step region and such that said high pressure fill hole is covered by said outer step region. 7. The fan drive of claim 1, wherein said disengaged position is characterized such that said low pressure fill hole is covered by said inner step region and such that said high pressure fill hole is covered by said outer step region. 8. The fan drive of claim 1 further comprising:an external controller; andan electrical coil electrically coupled to said external controller, said electrical coil capable of being electrically activated by said external controller to generate a magnetic flux, wherein a relative increase in amount of said magnetic flux thereby causing the movement of said actuator piston away from said spring in response to said relative increase and wherein a relative decrease in said amount of magnetic flux causes the movement of said actuator piston towards said spring in response to said relative decrease. 9. The fan drive of claim 8 further comprising at least one sensor input electrically coupled to said external controller, said at least one sensor input capable of sensing the temperature of the internal combustion engine, wherein said external controller interprets said sensed temperature to determine the amount of electrical signal to send to said electrical coil in response to said sensed engine operating condition to maintain said engine in a desired operating range. 10. A method for controlling the output speed of an electronically controlled viscous fan drive to control the temperature of a internal combustion engine within a desired operating range at a given input speed, the fan drive having a working chamber defined between an input coupling member and an output member, the method comprising:coupling an accumulator to an input coupling assembly of the electronically controlled viscous fan drive, said accumulator having a low pressure fill hole and a high pressure fill hole, wherein said accumulator and input coupling member also define a fluid reservoir chamber, wherein said fluid reservoir chamber is fluidically coupled to the working chamber through said low pressure fill hole and said high pressure fill hole;coupling said input coupling assembly to an actuator shaft;coupling a valve disk to said actuator shaft within said fluid reservoir chamber;coupling a spring around said actuator shaft between an actuator piston and said valve disk;coupling said actuator piston to an actuator, said actuator piston capable of moving actually along the length of said input coupling assembly away from said spring in response to an increasing amount of strength of a magnetic flux generated from electrically activating said actuator, thereby causing said valve disk to be pulled in response to said movement of said actuator piston against said spring;controlling the amount of said magnetic flux from said actuator to said actuator piston, thereby controlling the positioning of said valve disk to control the amount of a viscous fluid flowing from said fluid reservoir chamber to the working chamber, which in turn controls the amount of slippage between said input coupling member and output member within said working chamber to drive the output member. 11. The method of claim 10, wherein said spring is naturally biased against said valve disk in the absence of said magnetic flux from said actuator such that said valve disk is in a filly engaged position, said fully engaged position characterized by said valve disk being positioned such that said low pressure fill hole and said high pressure fill hole are uncovered, thereby allowing the maximum flow of said viscous fluid from said fluid reservoir chamber to the working chamber at the given input speed. 12. The method of claim 11, wherein said actuator piston moves said valve disk from said fully engaged position to a disengaged position in response to a first magnetic flux from said actuator such that said valve disk covers said high pressure fill hole and said low pressure fill hole, thereby preventing the flow of said viscous fluid from said fluid reservoir chamber to the working chamber at the given input speed. 13. The method of claim 11, wherein said actuator piston moves said valve disk from said fully engaged position to a partially en gaged position in response to a first magnetic flux from said actuator, said partially engaged position therein restricting, but not preventing, the flow of said viscous fluid from said fluid reservoir chamber to said working chamber at a given input speed. 14. The method of claim 13, wherein said actuator piston moves said valve disk from said partially engaged positioned to a disengaged position in response to a second magnetic flux, said second magnetic flux being greater than the amount of said first magnetic flux, such that said valve disk covers said high pressure fill hole and said low pressure fill hole, thereby preventing the flow of said viscous fluid from said fluid reservoir chamber to the working chamber at the given input speed. 15. The method of claim 13, wherein said actuator piston moves said valve disk from said partially engaged positioned to a fully engaged position in response to a second magnetic flux, said second magnetic flux being less than the amount than said first magnetic flux, said fully engaged position characterized by said valve disk being positioned such that said low pressure fill hole and said high pressure fill hole are uncovered, thereby allowing the maximum flow of said viscous fluid from said fluid reservoir chamber to the working chamber at the given input speed. 16. The method of claim 10, wherein coupling said actuator piston to an actuator comprises:coupling said actuator piston to an actuator; andcoupling said actuator to an external controller, said external controller electrically coupled to an electrical coil, said external controller capable of electrically activating said electrical coil, said electrical coil generating an amount of magnetic flux proportional to the degree of electrical activation, wherein the increase in the amount of magnetic flux of causes said actuator piston to move away from said spring in response to said relative increase. 17. The method of claim 16 further comprising electrically coupling at least one input sensor to said external controller, said at least one input sensor used to determine to the temperature of the internal combustion engine and send an electrical signal to said external controller as a function of said sensed temperature, wherein said external controller interprets said electrical signal to determine the amount of electrical activation of said electrical coil to maintain the internal combustion engine within a desired operating temperature range. 18. A method for preventing morning sickness in an electronically controlled viscous fan drive, the viscous fan drive the fan drive having a working chamber defined between an input coupling member and an output member, the input coupling member being coupled to and rotating about an input coupling assembly at a given input speed, the input coupling member being coupled to an actuator shaft, said output member driven as a function of the given input speed and the amount of a viscous fluid contained in the working chamber, the method comprising:providing an accumulator having an inner plate region, an inner circular ring having an inner top surface, an outer circular ring having an outer top surface and a pair of outer open regions;coupling said accumulator to the input coupling assembly of the viscous fan drive such that said inner top surface and said outer top surface are substantially sealed to said input coupling member, therein defining a fluid reservoir chamber and an anti-bleedback chamber, wherein said fluid reservoir chamber is fluidically coupled with said anti-bleedback chamber by a low pressure fill hole and by a high pressure fill hole,wherein the coupling also defines a fluid operating chamber between said accumulator, said input coupling member and a cover member, said fluid operating chamber fluidically coupling said pair of outer open regions of said accumulator to the working chamber;wherein the relative location of said pair of outer regions and said low pressure fill hole and high pressure fill hole are designed to prevent the flow of a viscous fluid from said fluid reservoir chamber to said fluid operating chamber when the given input speed is zero. 19. The method of claim 18, wherein providing an accumulator comprising molding an accumulator having an inner plate region, an inner circular ring having an inner top surface, an outer circular ring having an outer top surface and a pair of outer open regions. 20. An electronically controlled viscous fan drive used on an internal combustion engine comprising:an actuator capable of generating a magnetic flux;a housing member;a cover member coupled to said housing member;an actuator shaft coupled to said actuator and partially disposed within said housing member and said cover memberan input coupling assembly coupled to said actuator shaft, said input coupling assembly capable of rotating at an input speed;an input coupling member coupled to said input coupling assembly and disposed within said housing member and said cover member, said input coupling member and said cover member defining a working chamber therebetween;an accumulator coupled to actuator shaft and sealed to said input coupling member, said accumulator having an inner circular ring and an outer circular ring and a plate portion, said inner circular ring and said outer circular ring defining an anti-bleedback chamber, said anti-bleedback chamber having a pair of outer regions;a fluid reservoir chamber defined by said inner circular ring, said plate portion, and said input coupling member, said fluid reservoir chamber in fluid communication with said working chamber;a pumping element coupled between said working chamber and said fluid reservoir chamber through said cover member;a fluid operating chamber defined by said accumulator, said cover member, and said input coupling member, said fluid operating chamber in fluid communication with said working chamber and each of said pair of outer regions;a low pressure fill hole contained within said inner circular ring, said low pressure fill hole capable of moving a quantity of a viscous fluid from said reservoir chamber to said anti-bleedback chamber;a high pressure fill hole contained within said inner circular ring, said high pressure fill hole capable of moving a quantity of said viscous fluid from said reservoir chamber to said anti-bleedback chamber;a two-piece valve disk coupled to said actuator shaft and disposed within said fluid reservoir chamber, said two-piece valve disk having an inner disk and an outer disk;an actuator piston coupled around a portion of said actuator shaft, said actuator piston capable of axial movement along the length of said input coupling assembly in response to said nagnetic flux to position said two piece valve disk in either an engaged position, a partially engaged position, or in a disengaged position; anda spring coupled to said actuator shaft and to said inner disk such that said spring is between said inner disk and said actuator piston, said spring normally biasing said inner disk in said engaged position in the absence of said magnetic flux of said actuator. 21. The fan drive of claim 20, wherein said accumulator comprises a molded plastic accumulator. 22. The fan drive of claim 20, wherein said engaged position is characterized such that said inner disk is positioned wherein said low pressure fill hole is not covered and wherein said high pressure fill hole is not covered by said outer disk. 23. The fan drive of claim 20, wherein said partially engaged position is characterized such that said low pressure fill hole is not covered by said inner disk and such that said high pressure fill hole is partially covered by said outer disk. 24. The fan drive of claim 20, wherein said partially engaged position is characterized such that said low pressure fill hole is not covered by said inner disk and such that said high pressure fill hole is covered by said outer disk. 25. The fan drive of claim 20, wherei n said partially engaged position is characterized such that said low pressure fill hole is partially covered by said inner disk and such that said high pressure fill hole is covered by said outer disk. 26. The fan drive of claim 20, wherein said disengaged position is characterized such that said low pressure fill hole is covered by said inner disk and such that said high pressure fill hole is covered by said outer disk. 27. The fan drive of claim 20, further comprising:an external controller; andan electrical coil electrically coupled to said external controller, said electrical coil capable of being electrically activated by said external controller to generate a magnetic flux, wherein a relative increase in amount of said magnetic flux thereby causing the movement of said actuator piston away from said spring in response to said relative increase and wherein a relative decrease in said amount of magnetic flux causes the movement of said actuator piston towards said spring in response to said relative decrease. 28. The fan drive of claim 27 further comprising at least one sensor input electrically coupled to said external controller, said at least one sensor input capable of sensing the temperature of the internal combustion engine, wherein said controller interprets said sensed temperature to determine the amount of electrical signal to send to said electrical coil in response to said sensed engine operating condition to maintain said engine in a desired operating range.