WO1988005976A1

WO1988005976A1 - Dynamomagnetic machine

Info

Publication number: WO1988005976A1
Application number: PCT/US1988/000283
Authority: WO
Inventors: Tommy O. Franklin
Original assignee: Franklin's Magnetic Generator Corp.
Priority date: 1987-02-04
Filing date: 1988-02-01
Publication date: 1988-08-11

Abstract

A dynamomagnetic machine utilizes annular arrays of magnets (13) mounted to a rotor (10) and stator (11) such that the magnetic forces generated therebetween drive the rotor (10). This is specifically achieved by magnet mounting orientations, cyclically reorientation of magnets and the use of magnetic insulation (96).

Description

DYNAMOMAGNETIC MACHINE

TECHNICAL FIELD

This invention relates to dynamomagnetic machines by which magnetic energy is converted into mechanical energy.

BACKGROUND OF THE INVENTION

As exemplified by U.S. Patent Nos. 4,114,057, 4,233,532. 4.441,043 and 4-551,645, dynamoelectric machines have heretofore employed magnets for purposes other than for providing magnetic fields in which armatures are rotated to generate electric current. For example, auxiliary magnets have been used to provide interaction induction. The present inventive concept also utilizes arrangements of magnets on both rotary and stationary elements. However, the invention here is directed towards a means of generating rotary torque per se. Such torque may be used as mechanical power or to generate electrical power. Thus, where the dynamomagnetic machine is associated with an electric generator, it is done so for the purpose of providing mechanical power to rotate its armature.

'^" SUMMARY OF THE INVENTION In one form of the invention a dynamomagnetic machine comprises a stator having a set of stator magnets mounted as an annular array about a stator axis. A rotor is mounted for rotary movement also about the stator axis. The rotor has a set of rotor magnets mounted as an annular array about the stator axis in general axial alignment with the set of stator magnets. The magnets of at least one of the sets of magnets are mounted with their poles radially skewed with respect to the stator axis.

In another form of the invention a dynamomagnetic machine comprises a stationary member and a rotary member mounted for rotation with respect to the stationary member about an axis of rotation. The stationary member has a set of magnets mounted about the axis adjacent the rotary member. The rotary member has a set of magnets about the axis adjacent the stationary member set of magnets with like poles of the sets of magnets being adjacent. The magnets of at least one of the sets of magnets are mounted with their poles aligned parallel with and offset from radials of the axis of rotation.

In another form of the invention a dynamomagnetic machine comprising a stator having a set of stator magnets mounted as an annular array about a stator axis and a rotor mounted for rotary movement about the stator axis that has a set of rotor magnets mounted as an annular array about- the stator axis. The machine also has means for cyclically reorienting the magnet of one of the sets as they pass the magnets of the other set such that the net magnetic forces generated between the two sets of magnets drive the rotor about the stator axis. In yet ' another form of the invention, a dynamomagnetic machine comprising a stator having a set of stator magnets mounted as an annular array about a stator axis and a rotor mounted for rotary movement about the stator axis that has a set of rotor magnets mounted as an annular array about the axis. The machine also comprises magnetic insulation means for magnetically insulating the magnets of one set from those of the other set during a portion of their mutual passage such that the net magnetic force generated between the two sets of magnets drives the rotor in a rotary direction about the stator axis.

BRIEF DESCRIPTION OF THE DRAWING Fig. 1 is a partial, cross-sectional view of a dynamomagnetic machine embodying principles of the present invention.

Fig. 2 is a perspective view of an electric power generator that employs a dynamomagnetic machine of the present invention as shown in Fig. 1. Figs. 3a-3c are three cross-sectional views showing relative positions in sequence of one rotor magnet with respect to one stator magnet of the dynamomagnetic machine shown in Figs. 1 and 2.

Fig. 4 is a partial, cross-sectional view of a dynamomagnetic machine embodying principles of the invention in another preferred form.

Fig. 5 is a partial, cross-sectional view of a dynamomagnetic machine embodying principles of the invention in yet another form. Figs. βa-6c are three diagrammatical views showing relative positions in sequence of a rotor magnet with respect to a stator magnet of the dynamomagnetic machine partially shown in Fig. 5. Fig. 7 i-s an exploded view of a dynamomagnetic machine embodying principles of the invention in yet another form with certain details shown only in an enlarged view illustrated in Fig. 7a.

Fig. 8 is a side view of a portion of a dynamomagnetic machine embodying principles of the invention in still another form.

Fig. 9 is a sectional end view of a portion of the dynamomagnetic machine shown in Fig. 8.

DETAILED DESCRIPTION

With reference next to the drawing, there is shown in Fig. 1, in partially diagrammatical form for clarity of explanation, a dynamomagnetic machine or generator comprised of a rotor shown generally at 10 and a stator shown generally at 11. The rotor has a drive shaft 12 mounted by unshown bearing means for rotation about an axis 15 extending centrally along the shaft^{^}12. A set of permanent magnets 13 is mounted to the rotor as an annular array coaxially about the axis 15. The magnets 13 here are permanent type, preferably cast alnico or rare earth cobalt bar magnets, in the shape of slabs with opposite poles located on the principal surfaces of the slabs. Alternatively, of course, the magnets could be electro-magnet types as where, for example, the dynamomagnetic machine is quite large. In Fig. 1 each magnet is mounted with its poles skewed and aligned at an angle A with respect to a radial from axis 15 that passes centrally through the magnet midway between its two poles. With this orientation it is seen that each magnet has its poles aligned parallel with a radial from axis 15, with the magnet center offset by a distance S.

The stator 11 also has a set of permanent magnets 20 mounted thereto in axial alignment with and closely adjacent to the path of rotation of the annular array of rotor magnets 13. For clarity of illustration only two stator magnets 20 have been illustrated; however, a larger number such as 6 to 8 is preferably employed. The stator magnets are preferably stronger, e.g. twice as strong, as the rotor magnets. As with the case of the rotor magnets the stator magnets are also mounted at a skewed angle with respect to radials from axis 15 that passes centrally through the magnets midway between their two poles as located at opposed prinicipal surfaces of the magnets. Like poles of the rotor magnets 13 and the stator magnets 20 are adjacent. In this embodiment both rotor and stator magnets are oriented at a skewed angle A; however, it is only necessary that one of the two sets of magnets be so oriented, i.e., either the rotor or stator set may be oriented normally to radials from axis 15. Although the angle A drawn is smaller, an angle A of approximately 30° has been found to be optimum. Lesser angles, such as some 20° result in lesser power (and speed) being developed as the forces of repulsion become more radially directed. Greater angles, such as some 40° also produce less power with lessened field confrontation. Unshown switch means are employed for controllably arresting motion of the rotor in a generator off mode.

In Fig. 2 the just described dynamomagnetic machine or generator is seen to be mounted within an annular housing 21 that extends from a block shaped housing 22 to which an electric generator 23 of conventional construction is mounted. Here, the shaft 12 is seen to be coupled with the armature coil, partially shown at 24, of the electric generator 23 which armature is positioned for rotation within the magnetic field provided by two semi-cylindrical magnets 26. With this construction rotation of the shaft 12, created by the provision and arrangement of the rotor and stator magnets 13 and 20, causes the armature of the electric generator 23 to rotate within the magnetic field provided by the magnets 26 and thereby generate electric current which is delivered via power lines 27 to an ancillary load. These lines, as is well known, are coupled with the armature coil by means of slip rings and brush assemblies indicated generally at 28 within the housing of the electric power generator. The manner in which the dynamomagnetic machine or generator develops torque may be best understood by reference to Figs. 3a-3c. In Fig. 3b it is .seen that like poles of the two magnets are approximately, although not precisely, in alignment along a line 30 that extends to one side of the axis 15 of the rotor and stator. Since like poles are adjacent and are mutually repulsive, the force created by the magnets creates a coupling moment about the axis 15 causing the rotor to rotate in the direction indicated by the arrow in Fig. 3b. This provides an explanation of how the device operates.

Another method of understanding how the generator operates may be had by comparing Figs. 3a and 3c. As the rotor magnet 13 travels over the s^'tator magnet 20 the face of the rotor magnet 13 proximal to the stator magnet confronts the adjacent face of the stator magnet at an angle so as to create a unidirectionally rotary motion of the rotor with respect to the stator. More specifically, in Fig. 3a the approach of the magnet 13 to its point of perigee with magnet 20 is- resisted since adjacent poles are proximally positioned in their mountings. However, this confrontation is to a lesser spatial degree than that of Fig. 3c were the rotor to be attempting to rotate in the direction opposite to the arrow illustrated in that figure. The result is such that the net force imparted as magnet 13 swings past magnet 20, as shown occurring in Fig. 3, is greater than the net force of retardation shown in the approach of magnet 13 to magnet 20 as shown in Fig. 3a. Yet another way to visualize the inventive concept here is to consider the rotor magnets as analogous to the paddles of a water wheel. Obviously, the orientation of such paddles with respect to the wheel axis determines its direction of rotation where tne wheel is positioned directly beneath a stream of water gravitating down upon the wheel. This may therefore help in visualizing why it is uncecessary that both sets of magnets be at skewed angles.

The dynanomagnetic machine of Figs. 1-3 has been found to work well in generating relatively low forces, such as some 3-pound force or less, with the use of permanent type magnets. Higher force machines though have been found to be achievable through the selective use of magnetic insulation material and/or the use of means for reorienting magnets with respect to their mount or substrate as they make magnetic passes. For example. Fig. 4 illustrates a dynamomagnetic machine 40 having a stator 41 and a rotor 42 mounted for movement about a common stator and rotor axis 43. The rotor is seen to have a set of rotor magnets 44 rigidly mounted thereto with their poles oriented as shown at a skewed angle B which preferably in in the order of some 30".

The stator is seen to have a set of stator magnets 45 rigidly mounted thereto with their poles located as shown at a skewed angle such that passage of the rotor magnets thereby brings them in a mutually parallel relationship as their centers are aligned at perigee. In addition, the machine is seen to have strips of magnetic insulation material 46 mounted to magnets 45 so as to overlay their south poles. Though other suitable magnetic insulation materials are commercially available in mesh form, rubber has been found by applicant to provide good magnetic insulation in this application. in operation the dynamomagentic machine 40 operates in a mode very similar to that previously described in conjunction with the explanation of Figs. 1-3. Here however it may be appreciated that as the rotor rotates in the counterclockwise direction indicated by the arrow the magnetic insulation 46 will lessen the forces of repulsion as the south poles of the rotor magnets approach the south poles of the stator magnets. At the same time, the insulation will not tend to lessen the forces of repulsion provided as the north poles of the rotors pass the north poles of the stator magnets since the insulation does not extend over the north poles of the stator magnets. As a

• result, the dynamomagnetic machine of Fig. 4 has been found to be capable of generating greater power than the previously described embodiment.

Another technique employed in maximizing the driving forces and resultant power of dynamomagnetic machines is illustrated in that machine shown in Fig. 5 whose operation is sequentially shown in Figs. 6a-6e. In this case the stator 50 is provided with stator magnets 51 in an annular array about an unshown stator axis, similar to the other figures. Here, however, the north pole of the stator magnet shown is seen to be located adjacent the rotor 53 rather than on one of the ends of the magnets, as in Fig. 4. In addition, here the rotor 53 is seen to have a set of rotor magnets 54 that are mounted to the rotor for pivotable movement about a pivot 55 towards and away from the magnets of the stator 50. Movement is controlled by a camming mechanism that includes a cam follower 56 that is mounted on the end of an arm 57 for pivotable movement about a pivot axis 58. An end 57* of the arm is positioned so as to support that portion of the magnet

54 located distally from the pivot 55. The stator is provided with an endless camming surface 59 that is shaped to cam the cam follower 56 in its revolution about the stator and rotor common axes in producing the desired pivotal motion.

Figs. 6a-6e sequentially illustrate the pivotal movement of one rotor magnet 54 as it passes one stator magnet 51. In Fig. 6a it is seen that as the rotor magnet 54 approaches the stator magnet its south pole is drawn toward the north pole of the rotor magnet. It is also seen that no camming action is effected until the trailing edge of the rotor magnet 54 has reached the midway point along the rotor magnet. At this point the camming mechanism causes the rotor magnet 54 to pivot so that its trailing north pole is forced into close proximity with the north pole of the stator magnet 51. An angle of about 60° is finally achieved between the two magnets which is maintained, as shown in Figs. 6c and 6d, until the rotor magnet 54 has finished its pass by the stator magnet. This close proximity of the stator and rotor magnet produces substantial force which is used in driving the rotor. Following the passage of the rotor magnet pass the stator magnet the camming mechanism then returns the rotor magnet to its original postion as shown in the process of being done in Fig. 6e. Figs. 7 and 7a jointly illustrate another dynamomagnetic machine which utilizes rotating magnets to an advantage in maximizing the effects of forces generated between rotor and stator sets of magnets. Here, however,'^" it is the stator magnets rather than the rotor magnets which rotate or pivot with respect to their supporting structure.

In Fig. 7 a dynamomagnetic machine 70 is seen to have a rotor 71 and a stator 72 with the rotor having an annular array of permanent bar magnets 73 mounted thereto with their major surfaces oriented at a skewed angle to the flat, disc-shaped surface 74 of the rotor. The rotor also has a conical gear 75 that projects outwardly from the face 74 whose apex is located along a common stator and rotor axis. The stator 72 is also seen to have an annular array of stator magnets 77 that are seen to be larger and stronger than the rotor magnet 73. The mounting details of the stator magnets is omitted in Fig. 7, for clarity of explanation, but is shown in detail in Fig. 7a. Specifically, openings 79 are formed in the face 78 of the stator that faces the rotor. In each of these openings a stator magnet 77 is pivotally mounted for continuous rotation. Each stator magnet is mounted to an elongated cylindrical bar or axle 80 which extends through an outer bearing 81 and an inner bearing 82 radially from a common rotor and stator axis 85. A truncated conical gear 86 is mounted to the end of each axle 80 located closest to the axis 85 in mesh with the rotor gear 75. It thus is seen that as the rotor and its gear 75 rotates this action drives all of the stator gears 86 which in turn cause the stator magnets 77 to rotate continuously within the openings 79. The rotary positions of the stator magnets is selected such as to maximize the rotor driving forces generated between the rotor and stator magnets doing their mutual passages. Thus, approach repulsion is diminished as'^' much as possible by the poles of the rotor magnets 73 as they approach each of the stator magnets 77 and maximized upon departure. It should be appreciated here that the magnets of the rotor and stator face each other and are arranged along rotor and stator planes as opposed to the annular positions of the stator and rotor magnets in the previously described embodiments.

Finally, with reference to Figs. 8 and 9 yet another dynamomagnetic machine is shown which embodies principles of the invention and which might figuratively be considered as a water-wheel type embodiment. It is believed to have the potential for being the most powerful of the various embodiments. In this case magnetic insulation is again utilized as a means for maximizing the forces of repulsion between rotor and stator magnets in a desired direction of rotation. In this case the dynamomagnetic machine 90 is seen to have a rotor formed with a set of vanes or arms 91 that extend radially from a drive shaft 93. To the end of each vane is mounted a permanent magnet 92. The output power drive shaft 93 is rotatably mounted within sleeves or bearings 94. The stator here includes a set of annularly arranged tunnels 95 through which the rotor arms and magnets sequentially pass as the rotor rotates. These tunnels are of generally U-shaped configuration and are seen to have magnetic insulation material 96 on a portion thereof located distally from the rotor axis of rotation. To outer surfaces of each of the tunnels 95. are mounted stator magnets 97 with their south poles shown located just at ____ the exits of the tunnels. With this configuration as the north poles of the rotor magnets approach the north poles of the stator repulsion is lessened to a substantial degree by the presence of the magnetic

5 insulation material. However, once the rotor emerges from each tunnel its south pole is then positioned in close proximity to the south pole of the stator magnet. As a result, substantial force is imparted to the rotor magnets here which in turn causes the rotor to be the

10 driven.

In conclusion it is seen that a dynamomagnetic machine is provided by which mechanical torque can be developed from magnetic energy which may be used in numerous applications, both mechanical and electrical.

15 Though only preferred embodiments have been illustrated, many modifications, additions and deletions may be made thereto without departure from the spirit and scope of the invention as set forth in the following claims. 0

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5

Claims

1. A dynamomagnetic machine comprising a stator having a set of stator magnets mounted as an annular array about a 'stator axis, and a rotor mounted for rotary movement about said stator axis, said rotor having a set of rotor magnets mounted as an annular array about said stator axis in generally axial alignment with said set of stator magnets, and wherein the magnets of at least one of said set of magnets are mounted with their poles radially skewed with respect to said stator axis.

2. The dynamomagnetic machine of claim 1 wherein the magnets of each of said sets of magnets are mounted with their poles radially skewed with respect to said stator axis.

3. The dynamomagnetic machine of claim 2 wherein the magnets of each of said sets of magnets are mounted with their poles at substantially the same radially skewed angle with respect to said stator axis.

4. The dynamomagnetic machine of claim 1 wherein said stator and rotor magnets are mounted with like poles oriented adjacently.

5. The dynamomagnetic machine of claim 1 wherein the magnets of at least one of said set of magnets are permanent magnets.

6. The dynamomagnetic machine of claim 1 wherein said rotor is coupled with an electric power generator armature.

7. The dynamomagnetic machine of claim 1 wherein a portion of each magnet of one of said sets of magnets is overlaid with a magnetic insulator.

8. The dynamomagnetic machine of claim 1 wherein each magnet of one of said sets is mounted for pivotal movement, and wherein said dynamomagnetic machine further comprises means for pivoting each magnet of said one set as they pass each magnet of the other set.

9. A dynamomagnetic machine comprising a stationary member and a rotary member mounted for rotation with respect to said stationary member about an axis of rotation, said stationary member having a set of magnets mounted thereto about said axis adjacent said rotary member, said rotary member having a set of magnets mounted thereto about said axis adjacent said stationary member set of magnets with like poles of said sets of magnets being adjacent, and wherein the magnets of at least one of said sets of magnets are mounted with their poles aligned parallel with and offset from radials of said axis of rotation.

10. The dynamomagnetic machine of claim 9 wherein the magnets of each of said sets of magnets are mounted with their poles aligned parallel with and offset from radials of said axis of rotation.

11. The dynamomagnetic machine of claim 10 wherein the magnets of each of said sets of magnets are mounted with their poles aligned along common parallels.

12. The dynamomagnetic machine of claim 9 wherein the magnets of at least one of said sets of magnets are permanent type magnets.

13. The dynamomagnetic machine of claim 9 wherein said rotary member is coupled with the armature of an electric generator.

14. A dynamomagnetic machine comprising a stator having a set of stator magnets mounted as an annular array about a stator axis, a rotor mounted for rotary movement about said stator axis and having a set of rotor_, magnets mounted as an annular array about said stator axis, and means for cyclically reorienting the magnets of one of said sets as they pass the magnets of the other set such that the net magnetic forces generated between the two sets of magnets drive the rotor about the stator axis.

15. The dynamomagnetic machine of claim 14 wherein said stator magnets are cyclically reoriented by said reorienting means.

16. The dynamomagnetic machine of claim 15 wherein said reorienting means comprises a rotor gear mounted to said rotor and a stator gear linked with each of said magnets and located in mesh with said rotor gear.

17. The dynamomagnetic machine of claim 15 wherein said stator magnets are mounted to said stator for pivotal movement about an axis oriented generally parallel with said stator axis.

18. The dynamomagnetic machine of claim 14 wherein the magnets of one set are mounted for pivotal movement about an axis oriented generally radially of said stator axis.

19. The dynamomagnetic machine of claim 14 wherein said reorienting means comprises a cam and cam follower.

20. A dynamomagnetic machine comprising a stator having a set of stator magnets mounted as an annular array about a stator axis, a rotor mounted for rotary movement about said stator axis and having a set of rotor megnets mounted as an annular array about said stator axis, and magnetic insulation means for magnetically insulating said rotor magnets from said stator magnets during a portion of their passage past the stator magnets such that the net magnetic force generated between the two sets of magnets drive the rotor in a rotary direction about the stator axis.

21. The dynamomagnetic machine of claim 20 wherein said magnetic insulation means comprises magnetic insulation positioned between said stator magnets and rotor magnets as said rotor magnets approach said stator magnets in said rotary direction.