Title of Invention

MAGNETIC DRIVING PUMP OF VEHICLE INTERNAL COMBUSTION ENGINE

Abstract

N/AA-magnetic driving pump of vehicle internal combustion engine where permanent magnets, magnetized to have alternate N poles and S poles around an axial line of a drive shaft and a driven shaft, are respectively fixed to the drive shaft interlocked with a crankshaft and the driven shaft coaxially provided with the drive shaft.where in Mnnnn of Solution! Permanent magnets 25 and 26, magnetized to have alternate N poles and S poles 90 degrees or 180 degrees in phase in a peripheral direction, are respectively fixed to the drive shaft and the driven shaft 23. Fig. 2

Full Text

THE PATENTS ACT 1970 [39 OF 1970] PROVISIONAL/COMPLETE SPECIFICATION [See Section 10] "MAGNETIC DRIVING PUMP OF VEHICLE INTERNAL COMBUSTION ENGINE" HONDA GIKEN KOGYO KABUSHIKI KAISHA, a corporation of Japan, 1-1, Minamiaoyama 2-chome, Minato-ku, Tokyo, Japan The following specification particularly describes the nature of the invention and the manner in which it is to be performed :- The present invention relates to a magnetic driving pump for a vehicle internal combustion engine. [0001] [Technical Field of the Invention] The present invention relates to a magnetic driving pump of vehicle internal combustion engine in which permanent magnets, magnetized to have alternate N poles and S poles around an axial line of a drive shaft and a driven shaft, are respectively fixed to the drive shaft interlocked with a crankshaft and the driven shaft coaxially provided with the drive shaft. [0002] [Prior Art] Conventionally, a magnetic driving pump, in which mutually magnetizing permanent magnets are respectively fixed to a drive shaft driven by an electric motor and a driven shaft coaxially provided with the drive shaft, is known in, e.g., Japanese Published Unexamined Patent Application No. Sho 64-66490. [0003] [Problem to be Solved by the Invention] However, in this magnetic driving pump, a phase difference between magnetic poles of the permanent magnet on the drive shaft side and the permanent magnet on the driven shaft side increases by a resonance phenomenon due to variations in revolution on the drive shaft side and variations in revolution on the driven shaft side to which power is transmitted from the drive shaft side by the magnetic force. The phase difference may exceed a relative angle range of magnetic poles for power transmission between the drive shaft 2 and the driven shaft, and a power - transm.ittable torque between the drive shaft and the driven shaft is degraded by degradation of relative magnetic force. Then a step out (pull out) phenomenon in which the driven shaft side cannot rotate in correspondence with the drive shaft side may occur. [0004] Accordingly, in the magnetic driving pump disclosed in the above Japanese Published Unexamined Patent Application No . Sho 64-66490, an inertial moment of the drive shaft side is set to a value 4 or more times greater than that on the driven shaft side, thereby variations in revolution on the drive shaft side is suppressed, to attain mild acceleration and prevent the occurrence of the pull out phenomenon on the driven shaft side. [0005] However, in a magnetic driving pump where a drive shaft is interlocked with a crankshaft of internal combustion engine having a wide revolution area, especially internal combustion engine mounted on a vehicle, the occurrence of the pull out phenomenon on the driven shaft side cannot be completely prevented only by change in inertial mass as described above. [0006] The present invention has been made in view of the above situation, and has its object to provide a magnetic driving pump of vehicle internal combustion engine to reliably prevent the occurrence of the pull out phenomenon. [0007] [Means to Solve the Problem] 3 To attain the foregoing object, the invention in claim 1 is characterized in that in a magnetic driving pump of vehicle internal combustion engine, in which permanent magnets, magnetized to have alternate N poles and S poles around an axial line of a drive shaft and a driven shaft, are respectively fixed to the drive shaft interlocked with a crankshaft and the driven shaft coaxially provided with the drive shaft, the permanent magnets, magnetized to have alternate N poles and S poles 90 degrees or 180 degrees in phase in a peripheral direction, are respectively fixed to the drive shaft and the driven shaft. [0008] According to this construction, 4-pole or 2-pole permanent magnets where magnetic poles adjacent in a peripheral direction are different are respectively fixed to the drive shaft and the driven shaft. The driving force can be transmitted between the 4-pole or 2-pole permanent magnets within a range of 90 degrees or 180 degrees of mutual phase difference. As it is apparent from experimental results as shown in Fig. 3, the phase difference between the driven shaft and the drive shaft in use of 4-pole permanent magnets is 60 degrees at the maximum in an anteroposterior direction on one side, and there is an allowable phase difference of 30 degrees (=90-60) before the occurrence of pull out phenomenon. As the allowable phase difference is sufficient in consideration of changes in magnetic force due to temperature changes, a relative dimensional error between the permanent magnets upon assembly of pump, variation in inertial mass on the driven shaft side, and the width of variations in revolution on the internal 4 combustion engine side, the occurrence of the pull out phenomenon can be reliably prevented. Further, in use of 2-pole permanent magnets, the pull out phenomenon does not occur before the phase difference on the driving shaft side with respect to the driven shaft side becomes 180 degrees on one side. As there is a sufficient allowable phase difference, the occurrence of the pull out phenomenon can be reliably prevented as in the case of 4-pole permanent magnets. On the other hand, inuseof 6 or more pole permanent magnets , according to the experimental results shown in Fig. 3, there is merely an allowable phase difference of 15 degrees or less on one side before the occurrence of the pull out phenomenon. The allowable phase difference cannot be sufficient to prevent the occurrence of the pull out phenomenon. [0009] Further, in the invention in claim 2, in addition to the construction of the above-described invention in claim 1, one of the permanent magnets having a ring shape is provided in the inner perimeter of a cup-shaped rotary member fixed to the drive shaft, and the other one of the permanent magnets having a ring shape is fixed to the driven shaft in the portion coaxially covered with the rotary member. According to this construction, in comparison with the case where a pair of permanent magnets are provided at an interval in an axial direction, an area in which the respective magnetic poles of one permanent magnet face the other permanent magnet side can be increased, to increase transmission torque by the magnetic force. Further, an impeller or the like provided on the driven 5 shaft side can be provided more closely to the rotary member on the drive shaft side in the axial direction, thereby the inertial mass on the driven shaft side can be set to a small value, to increase the response of the driven shaft side and more reliably prevent the occurrence of the pull out phenomenon. [0010] Further, in the invention in claim 3, in addition to the construction of the above-described invention in claim 1 or 2, the drive shaft is a camshaft interlocked and connected with the crankshaft at a deceleration ratio of 1/2. According to this construction, as the number of revolutions of the camshaft is 1/2 of that of the crankshaft, variations in revolution of the drive shaft can be suppressed as much as possible, and the occurrence of the pull out phenomenon can be reduced. [0011] [Working Examples] Hereinbelow, an working example of the present invention will be described in accordance with an embodiment of the present invention as shown in the attached drawings. [Brief Explanation of the Drawings] [Fig. 1] A vertical cross-sectional view showing a part of the internal combustion engine. [Fig. 2] A cross - sectional view along the line 2-2 in Fig. 1. [Fig. 3] A diagram showing the experimental results of measurement of variations in revolution on the driving side 3-6- (o First, in Fig. 1, an engine main body 5 of a water-cooled internal combustion engine E mounted on e.g. a motorcycle has a cylinder block 6 with a cylinder bore 9 slidably engaged with a piston 8, a cylinder head 7 connected to the cylinder block 6, forming a combustion chamber 10 between a top of the piston 8 and the cylinder head, and a crank case (not shown) connected to the cylinder block 6, rotatably supporting the crankshaft 12 connected to the piston 8 via a connecting rod 11. Further, the cylinder block 6 and the cylinder head 7 are provided with a water jacket 13 to circulate cooling water. An ignition plug 14, facing the combustion chamber 10, is attached to the cylinder head 7. [0014] A valve chamber 16 is formed between the cylinder head 7 and a head cover 15 connected to the cylinder head 7. The valve chamber 16 includes an intake valve (not shown) to control supply of air-fuel mixture to the combustion chamber 10 and a valve mechanism 17 to drive an exhaust valve (not shown) to control exhaustion of burned gas from the combustion chamber 10. A camshaft 18 forming a part of the valve mechanism 17 is rotatably supported on the cylinder head 7 on an axial line parallel to the crankshaft 12. [0015] A drive sprocket 19 is fixed to the crankshaft 12. On the other hand, a driven sprocket 20 is fixed to the camshaft 18. An endless chain 21 is put around the driven sprocket 20 and the drive sprocket 19. By this arrangement, the revolution power of the crankshaft 12 is reduced at a deceleration ratio ^-2 of 1/2 and transmitted to the camshaft 18. [0016] The camshaft 18 also functions as a drive shaft of a water pump 22 as a magnetic driving pump according to the present invention. In the water pump 22, permanent magnets 25 and 26, magnetized to have alternate N poles and S poles around an axial line of the camshaft 18 and a driven shaft 23, are respectively fixed to the camshaft 18 as the drive shaft and the driven shaft 23 coaxially provided with the camshaft 18 and is provided with an impeller 24. [0017] Also referring to Fig. 2, a cup-shaped rotary member 27 pressed from e.g. a thin stainless steel plate is coaxially fastened, with the driven sprocket 20, to the camshaft 18 by plural bolts 28, 28. . . ., and the ring-shaped permanent magnet 25 is fixed to an inner perimeter of the rotary member 27. [0018] The impeller 2 4 is accommodated in an eddy chamber 3 0 formed in a pump housing 29. The pump housing 29 has a housing main body 31 with an open end opposite to the camshaft 18, and a pump cover 32 which closes the open end of the housing main body 31 by forming the eddy chamber 30 between the cover and the housing main body 31. The pump housing is fastened to the cylinder head 7 with a part of the housing main body 31 inserted into the cylinder head 7. [0019] The housing main body 31 of non-magnetic material has a bottomed cylindrical part 31a with a closed camshaft 18 side. The bottomed cylindrical part 31a is coaxially inserted into the permanent magnet 25 fixed to the inner perimeter of the rotary member 27 which rotates with the camshaft 18. [0020] Both ends of support shaft 33 coaxial with the camshaft 18 are fixed to the closed end of the bottomed cylindrical part 31a and the pump cover 32 in the housing main body 31. A cylindrical - shaped driven shaft 23 of e.g. synthetic resin, coaxially surrounding the support shaft 33, is rotatably supported by the support shaft 33. Further, the ring-shaped permanent magnet 26 is fixed to an outer perimeter of the driven shaft 23. [0021] The permanent magnet 26 is covered with a coating 34 of synthetic resin, and the impeller 24 is integrally formed with the coating 3 4 . That is, the impeller 24 is fixed to the driven shaft 23 via the coating 34 and the permanent magnet 26, and in a portion coaxially covered with the rotary member 27 where the ring-shaped permanent magnet 25 is fixed to the inner perimeter, the ring-shaped permanent magnet 26 is fixed to the driven shaft 2 3, with the bottomed cylindrical part 31a and the coating 34 positioned between the magnet 26 and the permanent magnet 25. [0022] An intake port 3 5 communicated with a central portion of the eddy chamber 30 is provided in a central portion of the pump cover 3 2, and cooling water taken from the intake port 3 5 into the eddy chamber 30 is pressed by rotation of the impeller 24. Then the cooling water discharged from the water pump 22 is supplied to the water jacket 13 of the engine main body 5 shown in Fig. 1, and the water jacket 13 is connected to a radiator (not shown). [0023] Further, the pump cover 32 includes a thermostat 36 . The thermostat 36 operates to select connection or disconnection of the intake port 3 5 with an exit of the radiator in correspondence with the temperature of the cooling water. That is, in a state where the cooling water temperature is low i.e. in a state where the internal combustion engine E is cooled, the cooling water from the water jacket 13 is restored to the water jacket 13 via the thermostat 36 and the water pump 22, while in a state where the cooling water temperature is high i.e. in a state where the internal combustion engine E has been warmed up, the cooling water is restored to the water jacket 13 via the radiator, the thermostat 36 and the water pump 22, thus the cooling water is cooled by radiation in the radiator. [0024] In the water pump 22 of this magnetic driving type, resonance may occur between variations in revolution of the camshaft 18 due to variations in revolution of the engine E and variations in revolution on the driven shaft 23 side to which the driving force is transmitted by the magnetic force from the camshaft 18. That is, as the driving side permanent magnet 2 5 rotates around the axial line, a force to restore the phase difference between the magnetic poles of the both permanent magnets 25 and 26 to "0" acts between the permanent 11 magnets 25 and 26 on the driving side and the driven side, and the restoration force changes to a nonlinear force in correspondence with the phase difference. If the restoration force is replaced by a spring force, a spring constant is reduced in accordance with increment of amplitude, and a natural oscillation is moved to a lower value. The movement of the natural oscillation causes resonance with the driving side on the driven side. This resonance may increase the phase difference between the driving side and the driven side even with a statically sufficient transmission torque, to case the pull out phenomenon. [0025] Accordingly, the present inventor performed an experiment by using actual startup of the internal combustion engine E mounted on a motorcycle, to check variations in revolution on the driven side with respect to the driving side when the number of magnetic poles are changed to 4 poles, 6 poles and 8 poles, in the permanent magnet 25 fixed to the inner perimeter of the rotary member 27 as the driving side and the permanent magnet 26 fixed to the outer perimeter of the driven shaft 23 as the driven side. Then experimental results were obtained as shown in Fig. 3. [0026] In Fig, 3, the vertical axis indicates the phase difference on one side of the driven side with respect to the driving side . The phase difference is represented by amplitude on the driven side with respect to the driving side in a full load state when the throttle of the internal combustion engine WE CLAIM : 1. A magnetic driving pump for a vehicle internal combustion engine, comprising: a driving shaft [18]; a driven shaft [23] mounted coaxially with said driving shaft [18]; and a pair of permanent magnets [25, 26], said pair of permanent magnets [25,26] being one of 4-pole and 2-pole permanent magnets where magnetic poles adjacent in a peripheral direction are different and are respectively fixed to said driving shaft [18] and said driven shaft [23], respectively, and being magnetized to have alternate N poles and S poles 90 degrees or 180 degrees in phase in a peripheral direction around an axis of said drive shaft[18]; wherein each of said pair of permanent magnets [25,26] is ring shaped, one of said permanent magnets [25] being provided within an inner perimeter of a cup-shaped rotary member [27] fixed to said drive shaft[18], and the other one of said permanent magnets [26] is fixed to said driven shaft [23] with at least a portion coaxially covered by said rotary member [27]. 2. The magnetic driving pump as claimed in claim 1 wherein said drive shaft [18] is interlocked with a crankshaft [12] of the engine, said drive shaft [18] being a camshaft interlocked and connected with said crankshaft [12] at a deceleration ratio of 1/2. 3. The magnetic driving pump as claimed in claim 1, comprising a pump housing [29], said driven shaft [23] being mounted for rotation within said pump housing [29]. 4. The magnetic driving pump as claimed in claim 3, wherein said driven shaft [23] includes an impeller [24] mounted for rotation therewith. 5. The magnetic driving pump as claimed in claim 1, wherein each of said pair of permanent magnets [25, 26] is a 2-pole permanent magnet. 6. The magnetic driving pump as claimed in claim 1, wherein each of said pair of permanent magnets [25,26] is a 4-pole permanent magnet. 7. A magnetic driving pump for a vehicle internal combustion engine substantially as hereinbefore described with reference to the accompanying drawings. Dated this 17/10/2001 [ JAYANTA PAL ) OF REMFRY & SAGAR ATTORNEY FOR THE^fPPLICANTS

Documents:

1016-mum-2001-abstract(26-07-2006).doc

1016-mum-2001-abstract(26-07-2006).pdf

1016-mum-2001-abstract.doc

1016-mum-2001-cancelled pages(26-07-2006).pdf

1016-mum-2001-claim(granted)-(26-07-2006).doc

1016-mum-2001-claims(granted)-(26-07-2006).pdf

1016-mum-2001-claims-canclled.pdf

1016-mum-2001-claims.doc

1016-mum-2001-claims.pdf

1016-mum-2001-correspondence(11-08-2006).pdf

1016-mum-2001-correspondence(ipo).pdf

1016-mum-2001-correspondence.pdf

1016-mum-2001-description(granted).doc

1016-mum-2001-description(granted).pdf

1016-mum-2001-drawing(26-07-2006).pdf

1016-mum-2001-form 1(17-10-2001).pdf

1016-mum-2001-form 1.pdf

1016-mum-2001-form 18(6-10-2005).pdf

1016-mum-2001-form 18.pdf

1016-mum-2001-form 2(granted)-(26-07-2006).doc

1016-mum-2001-form 2(granted)-(26-07-2006).pdf

1016-mum-2001-form 2(granted).doc

1016-mum-2001-form 2(granted).pdf

1016-mum-2001-form 2(title page).pdf

1016-mum-2001-form 3(17-10-2001).pdf

1016-mum-2001-form 3(26-07-2006).pdf

1016-mum-2001-form 3(8-01-2002).pdf

1016-mum-2001-form 3.pdf

1016-mum-2001-form 5(17-10-2001).pdf

1016-mum-2001-form 5.pdf

1016-mum-2001-other.pdf

1016-mum-2001-petition under rule 137.pdf

1016-mum-2001-petition under rule 138(26-07-2006).pdf

1016-mum-2001-petition under rule 138.pdf

1016-mum-2001-power of authority(18-03-2002).pdf

1016-mum-2001-power of authority(26-07-2006).pdf

1016-mum-2001-power of authority.pdf

1016-mum-2001-united states patent.pdf

1016-mum-2001-ups document.pdf