Hereafter, a magnetic power transmission system according a first embodiment of the present invention, will be described with reference to the drawings. The first embodiment is an example in which the magnetic power transmission system of the present invention is applied to a differential unit of a vehicle drive system.
In the vehicle 2, torque of the engine 3 is changed in speed by the automatic transmission 4, and then transmitted to the left and right drive wheels 6 and 6 via the magnetic power transmission system 1, and the left and right drive shafts 5 and 5, respectively.
The automatic transmission 4 includes a torque converter 4a connected to a crankshaft 3a of the engine 3, a main shaft 4b integrally formed with an output shaft of the torque converter 4a, an auxiliary shaft 4c parallel to the main shaft 4b, a gear mechanism 4d having a plurality of gear positions formed by a plurality of gear pairs (only one of which is shown) arranged on the shafts 4b and 4c, an output gear 4e disposed on the auxiliary shaft 4c, a clutch mechanism (not shown) for selectively switching the gear positions of the gear mechanism 4d, ands so forth.
In the automatic transmission 4, the gear positions of the gear mechanism 4d are selectively switched according to a speed change command from a control system, not shown, and torque transmitted from the engine 3 via the torque converter 4a is changed to a rotational speed dependent of the gear position of the gear mechanism 4d to be transmitted to the magnetic power transmission system 1 via the output gear 4e.
Next, a description will be given of the magnetic power transmission system 1.
As shown in
On the other hand, the outer rotor 11 includes a rotational shaft 11a, and a pair of left and right disks 11b and 11b concentrically formed on the rotational shaft 11a. The rotational shaft 11a is concentric with the shafts 10c of the casing 10, for extending through inner holes thereof, and its left end is connected to the drive shaft 5. Further, the right disk 11b is fixed to the right end of the rotational shaft 11a, and the left disk 11b is fixed to a predetermined portion of the rotational shaft 11a with a predetermined distance between the same and the right disk 11b.
The left and right disks 11b and 11b are each made of a soft magnetic material element, and on opposed surfaces thereof, left and right permanent magnet rows are formed in plane symmetry with each other at respective locations closer to outer peripheral ends of the surfaces. The left and right permanent magnet rows are each comprised of m (m is an integer) permanent magnets 11c, and the permanent magnets 11c are mounted to the disks 11b in a state in which the permanent magnets 11c and 11c opposed to each other are arranged to have the same polarities. Further, in each permanent magnet row, the m permanent magnets 11c are arranged at predetermined equal intervals such that the magnetic poles of each adjacent two of the permanent magnets 11c and 11c have polarities different from each other.
Further, the inner rotor 12 includes a rotational shaft 12a concentric with the rotational shaft 11a of the outer rotor 11, and a hollow cylindrical casing portion 12b concentrically and integrally formed with the rotational shaft 12a. The rotational shaft 12a has a right end connected to the drive shaft 5. Further, the casing portion 12b has a left end formed with a permanent magnet row disposed in the center of the two permanent magnet rows of the outer rotor 11 in a manner opposed thereto. This permanent magnet row is formed of m permanent magnets 12c.
The permanent magnets 12c are mounted to the casing portion 12b in a state in which they are arranged such that polarities on the left and right sides of each adjacent two of the permanent magnets 12c and 12c are different from each other. Further, the m permanent magnets 12c are provided such that they are in plane symmetry with the above-described m permanent magnets 11c when the outer rotor 11 and the inner rotor 12 have a predetermined rotational position relationship therebetween. More specifically, the permanent magnets 12c are arranged such that they are identical to the permanent magnets 11c in number, pitch, and the radial distance from the center of rotation. Furthermore, the opposite side surfaces of each permanent magnet 12c have approximately the same area and shape as those of an end face of each permanent magnet 11c opposed thereto.
It should be noted that in the present embodiment, one of the outer rotor 11 and the inner rotor 12 corresponds to first, third, and seventh movable members, and the other to second, fourth, and eighth movable members. Further, either of the left and right permanent magnets 11c, and the permanent magnets 12c correspond to first and third magnetic poles, and the other to second and fourth magnetic poles.
Furthermore, the intermediate rotor 13 rotates in unison with the casing 10, and includes a hollow cylindrical portion 13a rotatably fitted in the rotational shaft 11a, a left wall 13b radially extending from the left end of the hollow cylindrical portion 13a for being continuous with the inner wall of the casing 10, and a right wall 13c integrally formed with the right end of the hollow cylindrical portion 13a.
A left soft magnetic material element row is provided at a predetermined portion of the left wall 13b such that it is at the center between the left permanent magnet row of the outer rotor 11 and the permanent magnet row of the inner rotor 12 in a manner opposed thereto. The left soft magnetic material element row is comprised of m left soft magnetic material elements (e.g. laminates of steel plates) 13d, and the left soft magnetic material elements 13d are mounted to the left wall 13b such that they are in plane-symmetric relation with the above-described permanent magnets 11c or the permanent magnets 12c when the intermediate rotor 13 is in a predetermined rotational position relationship with the outer rotor 11 or the inner rotor 12. More specifically, the left soft magnetic material elements 13d are arranged such that they are identical to the permanent magnets 11c and the permanent magnets 12c in number, pitch, and the radial distance from the center of rotation. Furthermore, the opposite side surfaces of each left soft magnetic material element 13d have approximately the same area and shape as those of the end face of each permanent magnet 11c, and the opposite side surfaces of each permanent magnet 12c.
On the other hand, a right soft magnetic material element row is provided at a foremost end of the right wall 13c such that it is at the center between the right permanent magnet row of the outer rotor 11 and the permanent magnet row of the inner rotor 12 in a manner opposed thereto. The right soft magnetic material element row is formed of m right soft magnetic material elements (e.g. laminates of steel plates) 13e. The right soft magnetic material elements 13e are arranged such that they are identical to the left soft magnetic material elements 13d in pitch and the radial distance from the center of rotation, and mounted to the right wall 13b in a state circumferentially displaced from the left soft magnetic material elements 13d by a half of the pitch (see
Further, the distances between the respective opposite side surfaces of the left soft magnetic material element 13d, and the end face of the left permanent magnet 11c and the left side surface of the permanent magnet 12c, and the distances between the respective opposite side surfaces of the right soft magnetic material element 13e, and the end face of the right permanent magnet 11c and the right side surface of the permanent magnet 12c are set to be equal to each other.
It should be noted that in the present embodiment, the intermediate rotor 13 corresponds to fifth, sixth and ninth movable members, while one of the left and right soft magnetic material elements 13d and 13e corresponds to a first soft magnetic material element, and the other to a second soft magnetic material element.
Furthermore, the above-described casing 10 and three rotors 11 to 13 are supported by a large number of radial bearings and thrust bearings (none of which are shown in the figures), such that they are hardly changed in the mutual positional relationships in the direction of the rotational axis and the radial direction, and configured such that they are relatively rotatable with respect to each other about the same rotational axis.
Next, a description will be given of the operation of the magnetic power transmission system 1 configured as above. It should be noted that in the following description, the rotational speeds of the three rotors 11 to 13 are represented by V1 to V3, respectively, and torques of the three rotors 11 to 13 by TRQ1 to TRQ3. First, a case will be described with reference to
First, before the start of rotation of the inner rotor 12, when the opposite side surfaces of each permanent magnet 12c of the inner rotor 12 are at an opposed position where they are opposed to the respective end faces of the permanent magnets 11c and 11c of the outer rotor 11, due to the above-described arrangement, one of two pairs of magnetic poles opposed to each other have polarities different from each other, and the other have the same polarity. For example, as shown in
In this state, first magnetic lines G1 of force are generated between the magnetic pole of each left permanent magnet 11c, each left soft magnetic material element 13d, and the magnetic pole at the left-side portion of the permanent magnet 12c, and second magnetic lines G2 of force are generated between the magnetic pole of each right permanent magnet 11c, each right soft magnetic material element 13e, and a magnetic pole at a right-side portion of each permanent magnet 12c, whereby magnetic circuits as shown in
As described hereinbefore, the magnetic lines of force have a characteristic that when bent, they generate magnetic forces acting to reduce the lengths thereof, and therefore when the first magnetic lines G1 are bent, magnetic forces acting on the left soft magnetic material element 13d becomes larger as the degree of bend of the first magnetic lines G1, and the total magnetic flux amounts thereof are larger. More specifically, the magnetic force acting on the left soft magnetic material elements 13d is determined depending on the synergistic action of the degree of bend of the first magnetic lines G1 and the total magnetic flux amounts thereof. Similarly, also in a case where the second magnetic lines G2 are in a bent state, a magnetic force acting on the right soft magnetic material elements 13e is determined depending on the synergistic action of the degree of bend of the second magnetic lines G2 and the total magnetic flux amounts thereof. Therefore, in states shown in
When the inner rotor 12 rotates due to the torque TRQ2 from a position shown in
In this state, a considerably strong magnetic force acts on the left soft magnetic material element 13d by the synergistic action of the degree of bend of the first magnetic lines G1 and the total magnetic flux amounts thereof, and drives the left soft magnetic material elements 13d downward, as viewed in
Then, when the inner rotor 12 rotates from the position shown in
While the inner rotor 12 rotates from the position shown in
From this state, when the inner rotor 12 further rotates, the left soft magnetic material elements 13d are driven downward by a magnetic force generated by the synergistic action of the degree of bend of the first magnetic lines G1 and the total magnetic flux amounts thereof, while the right soft magnetic material elements 13e are driven downward by a magnetic force generated by the synergistic action of the degree of bend of the second magnetic lines G2 and the total magnetic flux amounts thereof, whereby the intermediate rotor 13 is rotated in the same direction as the direction of rotation of the inner rotor 12. In doing this, while the inner rotor 12 rotates to the position shown in
As described above, in accordance with the rotation of the inner rotor 12, a state is repeated in which the magnetic forces acting on the left soft magnetic material elements 13d, and the magnetic forces acting on the right soft magnetic material elements 13e are increased and decreased alternately, whereby the intermediate rotor 13 is driven, so that it is possible to transmit the torque TRQ2 input to the inner rotor 12 to the intermediate rotor 13. In this case, when torques transmitted via the left soft magnetic material element 13d, and the right soft magnetic material element 13e are represented by TRQ3d and TRQ3e, the relationship between torque TRQ3 transmitted to the intermediate rotor 13 and the torques TRQ3d and TRQ3e is generally as shown in
Further, as is clear from comparison between
It should be noted that during the rotation of the inner rotor 12 as described above, the intermediate rotor 13, while being pulled by the inner rotor 12, is rotated by the magnetic forces generated by the first magnetic lines G1 and the second magnetic lines G2, so that the intermediate rotor 13 rotates with a small phase delay with respect to the inner rotor 12. Therefore, when the inner rotor 12 is at the position shown in
Further, inversely to the above, when the inner rotor 12 is fixed (V2=0, TRQ2=0), and the TRQ1 is input to the outer rotor 11, in accordance with the rotation of the inner rotor 12, the state is repeated in which the magnetic forces acting on the left soft magnetic material elements 13d, and the magnetic forces acting on the right soft magnetic material elements 13e are increased and decreased alternately, whereby the intermediate rotor 13 is driven, as described above. As a result, it is possible to transmit the torque TRQ1 input to the outer rotor 11 to the intermediate rotor 13.
In doing this, for the above reason, the intermediate rotor 13 is driven such that it rotates at a value equal to one half of the rotational speed of the outer rotor 11. More specifically, V3=0.5×(V1+V2)=0.5×V1 holds (see
Next, a description will be given of a case in which the intermediate rotor 13 is fixed, and the torque TRQ2 is input to the inner rotor 12. First, it is assumed that before the start of rotation of the inner rotor 12, the three rotors 11 to 13 are in a positional relationship illustrated in
In this state, although magnetic forces are generated between the left and right soft magnetic material elements 13d and 13e, and the magnetic poles at the opposite-side portions of the permanent magnets 12c, by the synergistic action of the degree of bend of the first magnetic lines G1 and the second magnetic lines G2 and the total magnetic flux amounts thereof, the magnetic forces are not influential since the inner rotor 12 is driven by the torque TRQ2, and at the same time the left and right soft magnetic material elements 13d and 13e are fixed. Further, since the first magnetic lines G1 between the magnetic poles of the left permanent magnets 11c and the left soft magnetic material elements 13d are straight although their total magnetic flux amounts are large, no magnetic forces for driving the left soft magnetic material elements 13d are generated. On the other hand, the second magnetic lines G2 between the right soft magnetic material elements 13e and the magnetic poles of the right permanent magnets 11c generate magnetic forces for pulling the right permanent magnets 11c toward the right soft magnetic material elements 13e, by the synergistic action of the degree of bend of the second magnetic lines G2 and the total magnetic flux amounts thereof, whereby the outer rotor 11 is driven in a direction (upward as viewed in
While the outer rotor 11 rotates from the position shown in
When the inner rotor 12 and the outer rotor 11 are placed in a positional relationship shown in
From this state, when the inner rotor 12 rotates to a position shown in
When the inner rotor 12 rotates from the position shown in
As described above, along with the rotation of the inner rotor 12, the magnetic forces generated by the first magnetic lines G1 between the left soft magnetic material elements 13d and the left permanent magnets 11c, the magnetic forces generated by the second magnetic lines G2 between the right soft magnetic material elements 13e and the right permanent magnets 11c, and the magnetic forces corresponding to the difference between the above magnetic forces alternately act on the outer rotor 11, whereby the outer rotor 11 is driven in the direction opposite to the direction of rotation of the inner rotor 12. Therefore, it is possible to transmit the torque TRQ2 input to the inner rotor 12 to the outer rotor 11. In this case, as shown in
On the other hand, also when the intermediate rotor 13 is fixed, and the torque TRQ1 is input to the outer rotor 11, similarly to the above, the inner rotor 12 is driven such that it rotates at the same speed as that of the outer rotor 11 in the direction opposite to the direction of rotation thereof. In this case, as to the rotational speed, |V1|=|V2| holds, and as to the torque, TRQ1=TRQ2 holds.
Next, a description will be given of a case in which the three rotors 11 to 13 are all rotating.
Since the magnetic power transmission system 1 according to the present embodiment is used as a differential unit, the three rotors 11 to 13 are all rotating during traveling of the vehicle 2, and the relationship between the rotational speeds V1 to V3 is shown in
Further, when TRQ1≠0, TRQ2≠0, and TRQ3≠0, the torques of the three rotors 11 to 13 satisfy the relationship of TRQ1=TRQ2, and TRQ3=TRQ1+TRQ2. More specifically, the torque TRQ3 input to the intermediate rotor 13 is divided in two for being distributed to the outer rotor 11 and the inner rotor 12. It should be noted that inversely to the magnetic power transmission system 1 according to the present embodiment, also when both the outer rotor 11 and the inner rotor 12 are used as the torque input side, and the intermediate rotor 13 as the torque output side, the relationship of TRQ3=TRQ1+TRQ2 is satisfied.
As described above, according to the magnetic power transmission system 1 of the present embodiment, since torque input to any one of the three rotors 11 to 13 is transmitted to one or both of the other two rotors by magnetic forces, it is possible to execute the same torque-transmitting operation as carried out by the planetary gear unit, using the magnetic forces. Therefore, in a unit for carrying out the same torque-transmitting operation as executed by the planetary gear unit, it is possible to ensure advantageous effects peculiar to the magnetic power transmission system, that no lubricating structure is necessary, and there is no fear of generation of backlash or dusts at contact portions, for example. Further, when torque is transmitted, magnetic paths are formed using all of the left and right permanent magnets 11c and 11c, the left soft magnetic material elements 13d, the permanent magnets 12c, and the right soft magnetic material element 13e, so that it is possible to ensure the areas of the magnetic paths efficiently. As a result, compared with the conventional magnetic power transmission system which forms magnetic paths using only part of magnetic poles, it is possible to enhance the transmission efficiency of torque and transmission torque capacity, while maintaining the advantageous effects obtained by performing power transmission with magnetic forces.
Additionally, the magnetic power transmission system 1 can be realized by a relatively simple construction having the outer rotor 11 including the left and right permanent magnet rows, the inner rotor 12 having the permanent magnet row, and the intermediate rotor 13 including the left and right soft magnetic material elements, so that the manufacturing costs can be reduced compared with the conventional magnetic power transmission system provided with magnetic teeth having a complicated shape.
It should be noted that although the first embodiment is an example in which the magnetic power transmission system according to the present invention is applied to the differential unit for a vehicle, this is not limitative, but the magnetic power transmission system according to the present invention can be applied to torque-transmitting systems of various industrial apparatuses and devices, particularly to a torque-transmitting system required to perform such an operation as is carried out by the planetary gear unit. For example, the magnetic power transmission system according to the present invention may be applied to a power transmission system for a wind power generator.
Further, although the first embodiment is an example in which the left and right permanent magnets 11c and 11c, the permanent magnets 12c, the left and right soft magnetic material elements 13d and 13e are arranged in the same number at the same pitch, this is not limitative, but any suitable number and arrangement of these members may be employed insofar as the first magnetic rows and the second magnetic rows are generated such that torque transmission can be properly performed between the three rotors 11 to 13.
For example, the members may be arranged such that when each permanent magnet 12c is in a positional relationship with each of the left and right permanent magnets 11c and 11c, in which it is slightly displaced from a line connecting the centers of the left and right permanent magnets 11c and 11c, one of the left and right soft magnetic material elements 13d and 13e is in a position between the permanent magnets 11c and 12c, and the other thereof is in a position between each circumferentially adjacent two of the permanent magnets 11c and between those of the permanent magnets 12c. Further, the permanent magnets 11c and 11c, the permanent magnets 12c, and the left and right soft magnetic material elements 13d and 13e may be arranged in the same number at approximately equal intervals.
Furthermore, the left and right soft magnetic material elements 13d and 13e may be arranged in the same number at the same pitch such that the permanent magnets 11c and 11c and the permanent magnets 12c are arranged in the same number at the same pitch, and the number of the left and right soft magnetic material elements 13d and 13e is set to a value smaller than the number of the permanent magnets 11c and 11c and the permanent magnets 12c.
Next, a magnetic power transmission system 1B according to a second embodiment will be described with reference to
The magnetic power transmission system 1B includes a pair of left and right outer rotors 21 and 21, a pair of left and right inner rotors 22 and 22, a pair of left and right intermediate rotors 23 and 23, two pairs of bearings 24 each of which is formed by left and right bearings, and three gear shafts 25 to 26 provided in a rotatable manner. The pair of left and right outer rotors 21 and 21 are arranged at respective symmetrical locations, and hence the following description is given of the left outer rotor 21, by way of example.
The left outer rotor 21 includes a rotational shaft 21a, a disk 21b concentrically and integrally formed with the rotational shaft 21a, and a gear 21d. The rotational shaft 21a is rotatably supported by a pair of bearings 24 and 24. The disk 21b is formed of a soft magnetic material element, and has a permanent magnet row formed on a right side surface thereof, at a location closer to an outer peripheral end of the surface.
The permanent magnet row is comprised of m permanent magnets 21c. As shown in
On the other hand, the right outer rotor 21 is configured such that a gear 21d thereof is in constant mesh with a right gear 25a, described hereinafter, of the gear shaft 25, and in this state, the magnetic pole of each permanent magnet 21c has the same polarity as that of the magnetic pole of an axially corresponding one of the permanent magnets 21c of the left outer rotor 21. Otherwise, the right outer rotor 21 is configured similarly to the left outer rotor 21.
Further, the gear shaft 25 includes a pair of left and right gears 25a and 25a integrally formed therewith. As described above, the left and right gears 25a and 25a are in constant mesh with the gears 21d and 21d of the left and right outer rotors 21 and 21, respectively, whereby the left and right outer rotors 21 and 21 are configured such that they rotate in the same direction at the same speed while holing the positional relationship shown in
Further, the left and right inner rotors 22 and 22 are similarly configured, except for part thereof. First, a description will be given of the left inner rotor 22. The left inner rotor 22 includes a hollow cylindrical rotational shaft 22a concentrically fitted in a rotational shaft 23a of the intermediate rotor 23, described hereinafter, a disk 22b integrally formed with the rotational shaft 22a, and a gear 22d. The disk 22b is formed of a soft magnetic material element, and has a permanent magnet row formed on a left side surface thereof, at a location closer to an outer peripheral end of the surface, in a manner opposed to the permanent magnet row of the left outer rotor 21.
The permanent magnet row is comprised of m permanent magnets 22c. As shown in
On the other hand, the right inner rotor 22 is configured such that a gear 22d thereof is in constant mesh with a right gear 26a, described hereinafter, of the gear shaft 26, and in this state, the magnetic pole of each permanent magnet 22c has the same polarity as that of the magnetic pole of an axially corresponding one of the permanent magnets 22c of the left inner rotor 22. Otherwise, the right inner rotor 22 is configured similarly to the left inner rotor 22.
Further, the gear shaft 26 includes a pair of left and right gears 26a and 26a integrally formed therewith. As described above, the left and right gears 26a and 26a are in constant mesh with the gears 22a and 22a of the left and right inner rotors 22 and 22, respectively, whereby the left and right inner rotors 22 and 22 are configured such that they rotate in the same direction at the same speed while holing the positional relationship shown in
It should be noted that in the present embodiment, either of the left and right outer rotors 21 and 21, and the left and right inner rotors 22 and 22 correspond to first and third movable members, and the other to second and fourth movable members. Further, either of the left and right permanent magnets 21c and 21c, and the left and right permanent magnets 22c and 22c correspond to the first and third magnetic poles, and the other to the second and fourth magnetic poles.
Further, the left and right intermediate rotors 23 and 23 are similarly configured, except for part thereof. First, a description will be given of the left intermediate rotor 23. The left intermediate rotor 23 includes a hollow cylindrical portion 23a concentrically and rotatably fitted in the rotational shaft 21a, a left wall 23b integrally formed with the hollow cylindrical portion 23a, and a gear 23c. A left permanent magnet row is formed at a foremost end of the left wall 23b such that it is in a position between the left permanent magnet row of the left outer rotor 21 and the permanent magnet row of the left inner rotor 22 in a manner opposed thereto.
The left soft magnetic material element row is comprised of m left soft magnetic material elements 23d. The left soft magnetic material elements 23d are arranged in the same number at the same pitch as those of the permanent magnets 21c and the permanent magnets 22c such that they are identical to the permanent magnets 21c and 22c in the radial distance from the center of rotation. Additionally, the opposite side surfaces of each left soft magnetic material element 23d have approximately the same area and shape as those of the end faces of the respective permanent magnets 21c and 22c. Further, the gear 23c is in constant mesh with a left gear 27a, described hereinafter, of the gear shaft 27.
On the other hand, the right intermediate rotor 23 has a right soft magnetic material element row comprised of m right soft magnetic material elements 23e. The right soft magnetic material elements 23e are arranged in the same number at the same pitch as those of the permanent magnets 21c and the permanent magnets 22c such that they are identical to the permanent magnets 21c and 22c in the radial distance from the center of rotation. Additionally, the opposite side surfaces of each right soft magnetic material element 23e have approximately the same area and shape as those of the end faces of the opposed ones of the permanent magnets 21c and the permanent magnets 22c.
Further, in the right intermediate rotor 23, the gear 23c thereof is in constant mesh with a right gear 27a, described hereinafter, of the gear shaft 27, and in this state, the right soft magnetic material element 23e is disposed such that it is displaced from the left soft magnetic material element 23d by a half of the pitch in the direction of rotation of the right intermediate rotor 23.
On the other hand, the distances between the respective left and right side surfaces of the left soft magnetic material element 23d, and the end face of the permanent magnet 21c of the left outer rotor 21 and the end face of the permanent magnet 22c of the left inner rotor 22, and the distances between the respective left and right side surfaces of the right soft magnetic material element 23e, and the end face of the permanent magnet 21c of the right outer rotor 21 and the end face of the permanent magnet 22c of the right inner rotor 22 are set to be equal to each other.
It should be noted that in the present embodiment, one of the left and right intermediate rotors 23 corresponds to the fifth movable member, and the other to the sixth movable member. Further, one of the left and right soft magnetic material element 23d and 23e corresponds to the first soft magnetic material element, and the other to the second soft magnetic material element.
Further, the above six rotors 21 to 23 are supported by a large number of radial bearings and thrust bearings (none of which are shown in the figures), such that they are hardly changed in the positional relationships in the directions of the rotational axis and the radial direction, and configured such that they are relatively rotatable with respect to each other about the same rotational axis.
According to the magnetic power transmission system 1B of the second embodiment configured as described above, it is possible to obtain the same advantageous effects as provided by the magnetic power transmission system 1 according to the first embodiment. More specifically, it is possible to execute the same power-transmitting operation as carried out by the planetary gear unit, using the magnetic forces. Further, the areas of the magnetic paths can be ensured, whereby compared with the conventional magnetic power transmission system which forms magnetic paths using only part of magnetic poles, it is possible to enhance the transmission efficiency of torque and transmission torque capacity, while maintaining the advantageous effects obtained by performing power transmission with magnetic forces.
It should be noted that although the magnetic power transmission system 1B according to the second embodiment is an example in which the six rotors 21 to 23 as the first to sixth movable members are connected by the gear mechanism, this is not limitative, but the magnetic power transmission system according to the present invention may be configured such that the first movable member and the third movable member, the second movable member and the fourth movable member, and the fifth movable member and the sixth movable member move relative to each other in an interlocked manner, respectively. For example, the magnetic power transmission system according to the present invention may be configured such that two movable members move relative to each other in an interlocked manner by a combination of pulleys and belts.
Further, although the magnetic power transmission system 1B according to the second embodiment is an example in which the magnetic power transmission system according to the present invention is constructed symmetrically except for the polarities of the magnetic poles of the permanent magnets 22c of the left and right inner rotor 22, and the arrangement of the left soft magnetic material elements 23d and the right soft magnetic material elements 23e of the left and right intermediate rotors 23, this is not limitative, but the magnetic power transmission system according to the present invention may be constructed unsymmetrically. For example, the left and right rotors of the outer rotors 21 and 21, the inner rotors 22 and 22, and the intermediate rotors 23 and 23 may be configured to have diameters different from each other such that the numbers and the pitches of the permanent magnets 21c, the permanent magnets 22c, and the soft magnetic material elements 23d and 23e are different between the left and right rotors.
Next, a magnetic power transmission system 1C according to a third embodiment of the present invention will be described. As shown in
As shown in the figures, the magnetic power transmission system 1C includes the outer rotor 11, and left and right actuators 17 and 17. The outer rotor 11 includes the rotational shaft 11a, and left and right disks 11d and 11d concentric with the rotational shaft 11a. The left and right disks 11d and 11d are mounted to the rotational shaft 11a by being spline-fitted therein, respectively, whereby they are configured such that they are relatively axially movable with respect to the rotational shaft 11a, for rotation in unison with the rotational shaft 11a.
Further, the left and right actuators 17 and 17 (magnetic force-changing device) have the same arrangement, and hence the following description will be given of the left actuator 17, by way of example. The left actuator 17 includes a body 17a, and a rod 17b retractable with respect to the body 17a. A foremost end of the rod 17b is connected to the left disk 11d. This actuator 17 is electrically connected to a control system, not shown, and drives the left disk 11d between a transmitting position indicated by two-dot chain lines in
Similarly to the left actuator 17, the right actuator 17 as well is electrically connected to the control system, not shown, and drives the right disk 11d between a transmitting position indicated by two-dot chain lines in
In the magnetic power transmission system 1C, when the left and right disks 11d and 11d are at the transmitting positions, similarly to the above-described magnetic power transmission system 1 according to the first embodiment, torque is transmitted between the three rotors 11 to 13. For example, when the torque TRQ3 is input to the intermediate rotor 13, the torque TRQ3 is transmitted to the outer rotor 11 and the inner rotor 12, respectively.
From the above state, when the left and right disks 11d and 11d are driven from the transmitting positions to the blocking positions by the left and right actuators 17 and 17, magnetic resistance between each permanent magnet 12c and the permanent magnets 11c and 11c of the left and right disks 11d and 11d is increased to decrease the total magnetic flux amount. In accordance with the decrease in the total magnetic flux amount, torque capacity transmitted between the three rotors 11 to 13 is reduced. Then, when the left and right disks 11d and 11d are driven to the blocking positions, respectively, the total magnetic flux amount is extremely decreased, whereby a state is generated in which no torque is transmitted between the three rotors 11 to 13.
As described above, according to the magnetic power transmission system 1C of the third embodiment, it is possible to freely drive the left and right disks 11d and 11d between the transmitting positions and the blocking positions by the actuators 17 and 17. In this case, when the left and right disks 11d and 11d are held at the transmitting positions, it is possible to obtain the same advantageous effects as provided by the magnetic power transmission system 1 according to the first embodiment. Further, by driving the left and right disks 11d and 11d from the transmitting positions toward the blocking positions, it is possible to freely change transmission torque capacity between the three rotors 11 to 13. Particularly when the left and right disks 11d and 11d are driven to the blocking positions, it is possible to block torque transmission between the three rotors 11 to 13.
It should be noted that the method of changing transmission torque capacity between the three rotors 11 to 13 and blocking transmission torque is not limited to the above-described method according to the third embodiment, but the following method can be employed. For example, a magnetic power transmission system 1D as shown in
Further, a magnetic power transmission system 1E as shown in
Next, a magnetic power transmission system 1F according to a fourth embodiment of the present invention will be described with reference to
The magnetic power transmission system 1F includes a small-diameter rotor 31, a large-diameter rotor 32, and an intermediate-diameter rotor 33, and the three rotors 31 to 33 are supported by a large number of radial bearings and thrust bearings (none of which are shown in the figures), such that they are hardly changed in the mutual positional relationships in the direction of the rotational axis and the radial direction, and configured such that they are relatively rotatable with respect to each other about the same rotational axis.
The small-diameter rotor 31 includes a rotational shaft 31a connected to the drive shaft 5, and a turntable 31b integrally formed with a right end of the rotational shaft 31a. The turntable 31b is made of a soft magnetic material element, and has a laid-down H shape in cross-section. A permanent magnet row is axially formed on an outer peripheral surface thereof. The permanent magnet row is comprised of m permanent magnets 31c, which are arranged, as described hereinafter.
Further, the large-diameter rotor 32 includes a rotational shaft 32a concentric with the rotational shaft 31a of the small-diameter rotor 31 and connected to the drive shaft 5, and a hollow cylindrical casing portion 32b concentrically and integrally formed with the rotational shaft 32a. A ring 32d made of a soft magnetic material element is fixed to a foremost end of the casing portion 32b. A permanent magnet row is formed on the ring 32d in a manner opposed to the permanent magnet row of the large-diameter rotor 32. The permanent magnet row is comprised of m permanent magnets 32c, which are arranged, as described hereinafter.
It should be noted that in the present embodiment, one of the small-diameter rotor 31 and the large-diameter rotor 32 corresponds to the first, third, and seventh movable members, and the other to the second, fourth and eighth movable members. Further, one of the left and right permanent magnets 31c and 32c corresponds to the first and third magnetic poles, and the other to the second and fourth magnetic poles.
On the other hand, the intermediate-diameter rotor 33 includes a hollow cylindrical portion 33a rotatably fitted in the rotational shaft 31a, a gear 33b integrally formed with the hollow cylindrical portion 33a, in constant mesh with the output gear 4e of the automatic transmission 4, an annular protruding portion 33c protruding from a right side surface of the gear 33b, and left and right soft magnetic material element rows formed on the protruding portion 33c. The left and right soft magnetic material element rows are comprised of m left and right soft magnetic material elements 33d and 33e, respectively, and the left and right soft magnetic material elements 33d and 33e are arranged, described hereinafter.
It should be noted that in the present embodiment, the intermediate-diameter rotor 33 corresponds to the fifth, sixth and ninth movable members, while one of the left and right soft magnetic material elements 33d and 33e corresponds to the first soft magnetic material element, and the other to the second soft magnetic material element.
Further, the left and right soft magnetic material elements 33d and 33e are arranged such that they are circumferentially displaced from each other by a half of the pitch. Furthermore, the permanent magnets 31c are arranged such that the magnetic poles of each adjacent two thereof have polarities different from each other, and the permanent magnets 32c as well are arranged such that the magnetic poles of each adjacent two thereof have polarities different from each other. Additionally, the permanent magnets 31c, the permanent magnets 32c, the left soft magnetic material elements 33d, and the right soft magnetic material elements 33e are formed such that surfaces thereof opposed to each other have approximately the same area and shape.
Here, since two of the permanent magnets 32c and 32c, and the two rings 32d and 32d, shown in
Therefore, in the magnetic power transmission system 1F, the small-diameter rotor 31 corresponds to the aforementioned outer rotor 11, the large-diameter rotor 32 to the inner rotor 12, and the intermediate-diameter rotor 33 to the intermediate rotor 13, whereby the same torque-transmitting operation as executed by the three rotors 11 to 13 according to the first embodiment can be executed by the three rotors 31 to 33.
As described above, according to the magnetic power transmission system 1F of the fourth embodiment, it is possible to obtain the same advantageous effects as provided by the magnetic power transmission system 1 according to the first embodiment. More specifically, it is possible to execute the same power-transmitting operation as carried out by the planetary gear unit, using the magnetic forces. Further, compared with the conventional magnetic power transmission system which forms magnetic paths using only part of magnetic poles, it is possible to enhance the transmission efficiency of torque and transmission torque capacity, while maintaining the advantageous effects obtained by performing power transmission with magnetic forces. Additionally, the three rotors 31 to 33 are radially arranged side by side, whereby the axial sizes of the three rotors 31 to 33 can be made more compact than those of the three rotors 11 to 13 in the magnetic power transmission system 1 in which the three rotors 11 to 13 are arranged side by side in the axial direction.
Next, a magnetic power transmission system 1G according to a fifth embodiment of the present invention will be described with reference to
The left rotor 41 includes a rotational shaft 41a connected to the drive shaft 5, and a turntable 41b integrally formed with a right end of the rotational shaft 41a. The turntable 41b is made of a soft magnetic material element, and has a permanent magnet row axially formed at a portion closer to an outer periphery of a right side surface thereof. The permanent magnet row is comprised of m permanent magnets 41c, which are arranged, as described hereinafter.
The right rotor 42 includes a rotational shaft 42a concentric with the rotational shaft 41a of the left rotor 41 and connected to the drive shaft 5, and a turntable 42b integrally formed with a left end of the rotational shaft 42a. The turntable 42b is made of a soft magnetic material element, and has a permanent magnet row axially formed at a portion closer to an outer periphery of a right side surface thereof. The permanent magnet row is comprised of m permanent magnets 42c, which are arranged, as described hereinafter.
It should be noted that in the present embodiment, one of the left and right rotors 41 and 42 corresponds to the first, third and seventh movable members, and the other to the second, fourth, and eighth movable members. Further, one of the permanent magnet 41c and the permanent magnet 42c corresponds to the first and third magnetic poles, and the other to the second and fourth magnetic poles.
On the other hand, the intermediate rotor 43 includes a hollow cylindrical casing portion 43a, hollow shafts 43b and 43b integrally formed with the left and right sides of the casing portion 43a, for being rotatably fitted in the rotational shafts 41a and 42a, a gear 43c integrally formed with the casing portion 43a, in constant mesh with the output gear 4e of the automatic transmission 4, an annular protruding portion 43f protruding from an inner wall surface of the casing portion 43a, and outer and inner soft magnetic material element rows formed on the protruding portion 43f. The outer and inner soft magnetic material element rows are comprised of m outer and inner soft magnetic material elements 43d and 43e, respectively, and the outer and inner soft magnetic material elements 43d and 43e are arranged, described hereinafter.
It should be noted that in the present embodiment, the intermediate rotor 43 corresponds to the fifth, sixth and ninth movable members, while one of the outer and inner soft magnetic material elements 43d and 43e corresponds to the first soft magnetic material element, and the other to the second soft magnetic material element.
Further, the outer soft magnetic material elements 43d and the inner soft magnetic material elements 43e are arranged such that they are circumferentially displaced from each other by a half of the pitch. Furthermore, the permanent magnets 42c are arranged such that the magnetic poles of each adjacent two thereof have polarities different from each other. Additionally, the permanent magnets 41c, the permanent magnets 42c, the outer soft magnetic material elements 43d, and the inner soft magnetic material elements 43e are formed such that surfaces thereof opposed to each other have approximately the same area and shape.
On the other hand, since two of the permanent magnets 41c and 41c, and the two turntables 42b and 42b, shown in
Therefore, in the magnetic power transmission system 1G, the left rotor 41 corresponds to the aforementioned outer rotor 11, the right rotor 42 to the inner rotor 12, and the intermediate rotor 43 to the intermediate rotor 13, whereby the same torque-transmitting operation as executed by the three rotors 11 to 13 according to the first embodiment can be executed by the three rotors 41 to 43.
As described above, according to the magnetic power transmission system 1G of the fifth embodiment, it is possible to obtain the same advantageous effects as provided by the magnetic power transmission system 1 according to the first embodiment. Additionally, the axial sizes of the three rotors 41 to 43 can be made more compact than those of the three rotors 11 to 13 in the first embodiment, whereby the axial size of the whole system can be made compact.
Next, a magnetic power transmission system 1H according to a sixth embodiment of the present invention will be described with reference to
The outer slider 51 is made of a soft magnetic material element, and includes a flat top wall 51a extending in the front-rear direction, and left and right side walls 51b and 51b extending downward from opposite ends of the top wall 51a. Left and right permanent magnet rows are formed on inner surfaces of the side walls 51b and 51b in a manner extending in the front-rear direction. The respective left and right permanent magnet rows are comprised of a predetermined number of symmetrically arranged left and right permanent magnets 51c. As shown in
Further, a plurality of rollers 51d (only one of which is shown) are amounted to a lower end of each side wall 51b. The rollers 51d are accommodated within a guide rail 55 which is placed on a floor 54, for extending in the front-rear direction. With the above arrangement, when the driving force acts on the outer slider 51 in the front-rear direction, the plurality of rollers 51d roll while being guided by the guide rail 55, whereby the outer slider 51 moves in the front-rear direction.
Further, the inner slider 52 includes a body 52a extending in the front-rear direction along the side walls 51b and 51b of the outer slider, a plurality of rollers 52b (only one of which is shown) amounted to a lower end of the body 52a, and a permanent magnet row formed on an upper end of the body 52a. The permanent magnet row is comprised of a predetermined number of permanent magnets 52c. The permanent magnets 52c are arranged at the same intervals as the intervals at which the permanent magnets 51c are arranged, in the front-rear direction, such that the magnetic poles of each adjacent two of the permanent magnets 52c have polarities different from each other.
On the other hand, the rollers 52b are accommodated within a guide rail 56 which is placed on the floor 54, for extending in the front-rear direction. With the above arrangement, when the driving force acts on the inner slider 52 in the front-rear direction, the plurality of rollers 52b roll while being guided by the guide rail 56, whereby the inner slider 52 moves in the front-rear direction.
It should be noted that in the present embodiment, one of the outer and inner sliders 51 and 52 corresponds to the first, third and seventh movable members, and the other to the second, fifth, and eighth movable members. Further, either of the left and right permanent magnets 51c and the permanent magnets 52c correspond to the first and third magnetic poles, and the other to the second and fifth magnetic poles.
On the other hand, the intermediate slider 53 includes a flat top wall 53a extending in the front-rear direction, and left and right side walls 53b and 53b extending downward from opposite ends of the top wall 53a. A plurality of rollers 53c (only one of which is shown) are amounted to a lower end of each side wall 53b. The rollers 53c are accommodated within a guide rail 57 which is placed on the floor 54, for extending in the front-rear direction. With the above arrangement, when the driving force acts on the intermediate slider 53 in the front-rear direction, the plurality of rollers 53c roll while being guided by the guide rail 57, whereby the intermediate slider 53 moves in the front-rear direction.
Further, a left soft magnetic material element row is formed at the center of the left side wall in a manner extending in the front-rear direction. The left soft magnetic material element row is comprised of a predetermined number of left soft magnetic material elements 53d. As shown in
It should be noted that in the present embodiment, the intermediate slider 53 corresponds to the fifth, sixth and ninth movable members, while one of the left and right soft magnetic material elements 53d and 53e corresponds to the first soft magnetic material element, and the other to the second soft magnetic material element.
Further, in the magnetic power transmission system 1H, when the driving force is transmitted to any one of the outer slider 51, the inner slider 52, and the intermediate slider 53, the number of either of the left and right permanent magnets 51c and 51c, the left and right soft magnetic material elements 53d and 53e, or the permanent magnets 52c, of the slider to which the driving force is transmitted, is set to a value smaller than the numbers of the others.
The magnetic power transmission system 1H according to the sixth embodiment is configured as described above. As is clear from comparison between
Therefore, in the magnetic power transmission system 1H, the driving force acting in the front-rear direction can be transmitted between the three sliders 51 to 53 by magnetic lines generated between the permanent magnet 51c, the left soft magnetic material element 53d, the permanent magnet 52c, the right soft magnetic material element 53e, and the permanent magnet 51c. For example, when the outer slider 51 is fixed, and the driving force is input to the inner slider 52, it is possible to drive the intermediate slider 53 in the same direction at a half of the speed of the inner slider 52, and transmit a driving force twice as large as a value input to the inner slider 52 to the intermediate slider 53.
As described hereinabove, according to the magnetic power transmission system 1H, it is possible to transmit a driving force input to any one of the three sliders 51 to 53, as a driving force linearly acting on both or one of the other two sliders, by magnetic forces. In doing this, magnetic circuits are formed by using all of any of the left and right permanent magnets 51c and 51c, the left and right soft magnetic material elements 53d and 53e, or the permanent magnets 52c, of a slider to which the driving force is input, and hence it is possible to efficiently ensure the areas of magnetic paths. As a result, compared with the conventional magnetic power transmission system which forms magnetic paths using only part of magnetic poles, it is possible to enhance power transmission efficiency and power transmission capacity, while maintaining the advantageous effects obtained by performing power transmission with magnetic forces.
Additionally, the magnetic power transmission system 1H can be realized using a relatively simple arrangement of the intermediate slider 53 which is provided with the outer slider 51 including left and right permanent magnet rows, the inner slider 52 including a permanent magnet row, and the intermediate slider 53 including left and right soft magnetic material element rows.
It should be noted that although the magnetic power transmission systems according to the above-described embodiments are all examples in which use permanent magnets as magnetic poles, this is not limitative, but the magnetic power transmission system according to the present invention may be configured to employ electromagnets as magnetic poles.
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Number | Date | Country | Kind |
---|---|---|---|
213905/2006 | Aug 2006 | JP | national |