[001] The invention relates to a universal motor/generator. As a generator it is capable of generating both DC as well as AC at its output. The AC generated can be within a wide frequency range which is limited only by the electromagnetic properties of the rotor magnetic core material and excitation coils.

[002] The following invention can be considered an advanced and upgraded version of the famous Faraday disc generator, made by Michael Faraday during his experiments back in 1831. Also known as the Homopolar generator or unipolar generator, the original generator made by Faraday was the world’s first electromagnetic generator. It still is the only electromechanical generator known capable of producing DC voltage without commutators or rectifiers. The generator in its original form was made of a conductive disc rotor fixed to a rotating shaft and two current collectors in the form of carbon/graphite brushes that combined with a load resistance between them completed the electrical loop. One brush normally is attached to the axis or inner diameter of the conductive disc while the other brush is attached to the circumference or outer diameter of the disc. The generator also had a stationary permanent magnet located near the disc. The magnetic field lines cut the disc perpendicularly. As the disc rotates electron deflection and accumulation occurs between the center and periphery of the disc due to the Eorentz force law which states that a charged particle traveling through a magnetic field at 90 degree angle experiences a force that is both perpendicular to the B field and to the particles own original trajectory. The prior art is also disclosed in the Spanish patent application publication No. ES 2527783, in the US patent application publication No. US 3185877, in the international patent application publication No. WO2011/0211008 and Australian patent application publication No. AU2015201800.

[003] Eorentz law stipulates that a particle of charge q moving with a velocity v in an electric field E and a magnetic field B experiences a force of F=qE+qv*.B. For the classical permanent magnet Faraday disc the E field from the magnet may be ignored (because the magnet doesn’t have an E field in the stationary reference frame) and focus on the B field produced by the magnet. The E field is set up in the disc between its center and outer diameter as it rotates due to charge (free electron) deflection within the disc and accumulation. Although this prior-art design worked, the original Faraday disc was very inefficient and suffered from major drawbacks. Since the generating part of the device is the rotating disc in classical generator/motor analogy it can be thought of as a single wire loop.

[004] The equation for voltage produced by the rotating disc is this (without considering the air gaps) are as follows:

[005] The equation (1) illustrates that the voltage is proportional to the square of the radius, which explains why all the known discs that were used for either scientific or other purposes were of large diameter. Using the original brush contacts also means that with such a low voltage there are high ohmic losses in the brush contacts, especially the one located on the periphery of the disc. Here the surface velocity is large and the contact wears out fast and also produces arcing which results in a bad electrical connection. The original disc also had a magnet that did not cover the whole surface area of the disc which meant that in one part of the disc currents were generated center to rim (or vice versa) while in the other parts not covered by field lines this current was electrically shunted and short circuited. Later models avoided this problem by having a magnet whose field is homogeneous across the entire disc surface.

[006] Some later experiments conducted in the 20 ^th century used special current collection means like a spray of liquid metal (NaK) against the rim of the disc. One notable example was a generator built in the Australian National University for their synchrotron project.

[007] The main reason experiments and upgrades were carried out with the Faraday disc is because despite all its drawbacks its low internal resistance is capable of providing very large currents into low resistance electrical loads like large coils or welding machines.

[008] It should also be noted that it is impossible to design a generator of this type without a sliding electrical contact located at its periphery because the B field lines always form loops and the lines permeating the disc also cross the current return path connecting the disc center to periphery which means that if this electrical connection was attached and co -rotating with the disc it would generate current in the same direction as that in the disc and the two currents would cancel. It is impossible to create a geometry where the magnetic field would not loop back through some current generating part of the generator creating an opposing current within the loop. This is one of the reasons why the invention comprises a slotted conductive disc in order to use pole pairs. Each pole pair has a closed short length magnetic flux path.

[009] The drawbacks of the prior- art designs are as follows: (i) fast wearing high resistance sliding electrical contacts; (ii) non uniform magnetic field resulting in internal shunting of the disc; and (iii) sliding contacts using liquid metal that are hard to implement and toxic.

[010] But there are also some important properties to the generator, like (a) a low internal resistance, capability of very high current; (b) only DC producing generator capable of direct DC output; and (c) capability of AC output by using electromagnetic excitation.

[Oi l] Due to the underlying physical characteristics of this generator/motor the frequency or waveform of the AC generated is not related to the RPM of the rotor shaft, instead the electrical output of the generator in terms of frequency/waveform is fully independent of the RPM of the rotor shaft. The electrical output is thus shaped by a much smaller input signal that is applied to the excitation coils located on the rotor magnetic core. In this regard the device can be thought of as an electromechanical amplifier where much like in a solid state amplifier a lower amplitude input signal is amplified to a larger amplitude output signal preserving the shape and waveform characteristics of the signal.

[012] Similarly, the generator can be also driven as a motor, as such it can work both with DC as well as AC within a wide frequency range.

[013] This device offers some advantages compared to other methods of generating very high power AC waveforms, DC or pulsed power, namely it consists of robust copper and steel parts with no semiconductors or spark gaps or other wearable parts, given the layout of the conducting elements within the device it can also sustain prolonged periods of short circuit and other over design specification operation modes, which might be beneficial in science experiments and other demanding fields.

[014] The universal motor/generator works based on the Lorentz force law and can be considered an advanced version of the famous Faraday disc. The original Faraday disc or as it is also known as Homopolar generator had various drawbacks like fast degrading brush contacts, magnetic field inhomogeneities and others, that made the device inefficient as well as only allowed DC operation by using static magnetic field. In this device these drawbacks are eliminated by introducing a sealed, rotating liquid metal contact assembly as a means of current collection at the edge/periphery of the disc. Also, the original monolithic copper disc is separated into thin involute slots where all the individual slots are joined together by inner and outer rings forming a single piece part.

[015] The main parts of this generator/motor are the magnetic core together with excitation coils and involute shaped slotted copper discs that are joined at the periphery of the disc structure by a co-rotating liquid metal contact assembly which closes the electrical loop of the generator/motor.

[016] A generator/motor basically comprises three main assemblies: a rotor assembly, a rotating liquid metal contact assembly positioned around the rotor assembly and fixed to the rotor assembly, and a stator or a stator assembly.

[017] The rotating liquid metal contact assembly consists of two isolated electrodes attached to the assembly structure, a rotor with two electrodes and a liquid metal. The rotor is part of an electric motor formed by the stator located on the stationary support and electromagnetic pickup ring located on the side of the rotating liquid metal contact assembly facing the stationary stator forming an inductive coupling where power is transferred from stationary frame to the rotating frame.

[018] The rotor assembly comprises a rotor shaft which is mounted on bearings attached to the base so that the rotor shaft is rotatable. The rotor assembly further comprises a rotor cover fixed with to rotor shaft. The rotor cover may consist of two parts creating a casing which encloses other parts of the rotor assembly. The rotor assembly further comprises a first part of a rotor main magnetic core and a second part of a rotor main magnetic core opposed to the first part of the rotor main magnetic core. Both parts of the rotor main magnetic core are fixed to the rotor cover so that the cores can rotate together with the rotor cover and the rotor shaft. The rotor assembly further comprises a first slotted conductive disc and a second slotted conductive disc positioned between the both parts of the rotor main magnetic cores. The first slotted conductive disc and the second slotted conductive disc are shaped so that the discs do not cover the involute slots. The sections of the discs that are not slotted are positioned at the protrusions of the rotor main magnetic core so that these sections do not cover the slots of the rotor main magnetic core. Moreover, by introducing a time varying magnetic field means that the disc is broken up into thin slots much like the laminated electrical steel core of a transformer.

[019] Each part of the rotor main magnetic cores comprises involute slots and involute protrusions that are formed so that each involute slot and each involute protrusion of the first part of the rotor main magnetic core coincides with each involute slot and each involute protrusion of the second part of the rotor main magnetic core respectively. The rotor assembly further comprises excitation coils, where each excitation coil is wind around every second involute protrusion of the first part of the rotor main magnetic core.

[020] As mentioned above, around these magnetic core involuted protrusions are positioned the excitation coils. Once energized they form magnetic pole pairs, two slotted discs are located inside one rotor, so that one copper strip from one disc carries a centre to rim current as it goes through the magnetic pole field lines while the adjacent copper strip on the second disc traverses through returning B field lines of the same pole pair carrying a rim to centre current and closing the loop. Accordingly, many such parallel involute slots and strips are joined together all following the same principle.

[021] A support is fixed to the rotor cover so that the rotating liquid metal contact assembly can be fixed to the rotor assembly.

[022] The rotating liquid metal contact assembly comprises a toroidal casing. The toroidal casing comprises a main body, an end body and a toroidal stator ring. The main body, the end body and the toroidal stator ring are fixed together forming an enclosed hermetically sealed volume or toroidal casing. Within this volume liquid metal and inert gas atmosphere is formed. The rotating liquid metal contact assembly further comprises a ring-type rotor made of nonconducting material and disposed within the volume. The rotating liquid metal contact assembly further comprises a permanent magnet ring fixed to the rotor and positioned around its circumference and two rotor electrodes also fixed to the rotor. Both rotor electrodes are position a distance from each other. The liquid metal is arranged in the volume of the toroidal casing in close proximity of the rotor electrodes. A separator is positioned in the volume and configured to separate the liquid metal in two separate sections so that for each rotor electrode there is certain amount of the liquid metal. The rotating liquid metal contact assembly is provided with a pickup ring fixed thereto. The rotating liquid metal contact assembly further comprises two contact assembly electrodes. Both contact assembly electrodes are isolated from each other and one end of each contact assembly electrode is positioned in the volume and separated by the separator so that each contact assembly electrode is in contact with only one section of the liquid metal.

[023] The stator is positioned in proximity of the rotor assembly and the rotating liquid metal contact assembly. The stator comprises a stationary stator ring fixed to the stator. The stationary stator ring is arranged so that the magnetic transfer link is provided between the stationary stator ring and the pickup ring.

[024] The rotating liquid metal contact assembly further comprises a connector electrically connecting both rotor electrodes.

[025] The liquid metal is selected from the group comprising a mercury, gallium and eutectic alloy consisting of gallium, indium and tin. In certain embodiment of the invention other liquid metals and it allows may be used. For example, in another embodiment of the invention a caesium may be used.

[026] The generator/rotator further comprises a conductor connected between the pickup ring to the toroidal stator ring providing electric transfer therebetween.

[027] As the rotating liquid metal contact assembly starts to rotate the liquid metal inside the assembly starts to get dragged along the outer edge side of the assembly due to friction against the electrodes and also due to centripetal force acting on the heavy liquid mercury. Even at low RPM after a short while the liquid mercury forms a thin even layer spread out around the inner periphery of the assembly covering the surface of the electrodes attached to the assembly. On top of this layer of mercury sit the toroid shaped tube electrodes of the rotor, these electrodes are shunted electrically after periodic intervals through the rotor structure. The mercury layer also acts as a bearing and mechanical support for the rotor. As the assembly rotates, by applying a DC potential to the stator located on the stationary support structure, the rotor pickup ring receives power and the rotor inside the rotating liquid metal contact assembly is being held in place with respect to the rest of the assembly. [028] One can also make the rotor turn in reverse direction than that of the assembly by applying a time varying waveform to the stator located on the stationary support structure, this action is then comparable to frequency control of a permanent magnet motor. The rotor with electrodes inside the rotating contact assembly can be thought of as the classical brush contact equivalent applied to the disc edge of the classical Faraday disc.

[029] The output voltage from a Faraday disc is directly proportional to the magnetic field strength and disc RPM (revolutions per minute) with respect to brush contact (which under classic conditions is stationary), so by varying the RPM of the rotor inside the liquid metal contact assembly the output voltage is varied.

[030] The low electrical resistance of such a liquid metal contact is enhanced by the fact that even as the rotor’s toroidal electrodes will push the liquid metal away as they move through it the liquid metal will experience a constant back pressure due to centripetal force acting on it which will tend to constantly push the metal on the surface of the electrodes.

[031] Considering the Faraday disc working principle it is known that the current is generated within the disc due to the Lorentz force and from Lorentz force it is known that a charged particle experiences a deflection force while traveling through a magnetic field at an angle. If a charged particle travels through vacuum where a B field is present and the B field strength is changed, the change in deflection felt by the particle is almost instantaneous (changes in Em fields in vacuum travel at c).

[032] Faraday disc example indicates that as long as the magnetic field is static and the disc RPM is also fixed the output is a stable DC voltage, but if we were to alter the strength of the magnetic field cutting the disc the output voltage would change proportionally to the change in magnetic field strength. This happens because the output voltage of the disc is proportional to its RPM and magnetic field strength, also the diameter of the disc. Of all these three properties there is only one we can change fast enough in time and that is the strength of the magnetic field. In the following invention the electromagnet is introduced as the B field source for the disc. [033] If we consider a Faraday disc but with an electromagnet producing the magnetic field we see that if we spin the disc and supply the electromagnet with a 50 Hz sine wave frequency the output of the disc would also be a 50 Hz sine wave. The changes in the magnetic field are felt almost instantaneously by the free electrons within the disc and the current changes accordingly. The disc now becomes analogous to an amplifier, where the input signal is amplified at the output, but the shape of the signal is conserved. In fact it is an electromechanical amplifier.

[034] Any classical Faraday disc also has two brush contacts wherein the one is in the periphery of the disc while the other is either at some minor disc radius or at the axis.

[035] In the proposed invention, the rotating liquid metal contact assembly can be thought of as the peripheral brush contact for both of the two discs while there is no minor radius or rotor axis brush contact as would be in the classical Faraday disc. The reason for this is that this minor radius contact is actually not needed and is only used because of the need to close the circuit. Physics dictates that a deformable/moving electrical contact is only necessary in one place of a deformable circuit which is exposed to a magnetic field that loops through the circuit. This should also coincide with the place where the angular velocity of charged particles is the highest which is at the outermost radial parts of a disc.

[036] For example, if perfect conducting disc is spun in a homogeneous magnetic field the highest rate of change experienced by a free electron within the disc is at the periphery of the disc while at the very center of the disc there is no change at all and zero velocity for the electron. It is represented in the following equation:

E=(co ^x r)xB, (2) where E denotes the Electric field, co denotes angular velocity while r radius.

[037] If r is equal to zero, then multiplying by zero results in zero, so there is no voltage or current generated at the center of the disc, even for small r the total voltage still is very small which shows us that most of the current is generated within the outer larger radius of the disc.

[038] Another aspect of the invention is a use of Faraday paradox originally arose because M. Faraday observed that current/voltage is generated from the disc both when the disc rotates and magnet is stationary and also when both the disc and magnet rotate together. It was known as a paradox because in Faraday’s time the model of electrons and EM fields was not yet properly understood. Later with the help of A. Einstein’s theory of special relativity and also better understanding of electron flow within conductors this paradox was explained.

[039] In short, the explanation for the paradox is as follows. If the field produced by the magnet is homogeneous and covers the whole disc, then the field as such can be thought as separated from the magnet because if one was to rotate the magnet around its center axis the strength of its field would not change. On the other hand, the electrons within the disc are moving due to the rotational motion of the disc. The electrons within the disc are cutting B field lines nevertheless if the magnet is physically rotating with the disc or is stationary. We need to remember that magnetic lines of force are a human made construct to aide visual thinking and not a real phenomenon of nature. The only real property of a magnet is the strength of its field. The physical motion of a symmetrical disc shaped magnet around its axis of symmetry doesn’t change its field strength. This property is used in the invention to eliminate the otherwise necessary air-gap and assemble the device in such a way that the excitation field magnets and their cores are pressed together with the disc slots. In the geometry of my device this is also necessary.

[040] The drawings illustrate generally, by way of example, but not by way of limitation, various embodiments of the invention.

[041] Fig. 1 is a perspective view of one embodiment of a generator/motor.

[042] Fig. 2 is a cross-sectional view of the generator/motor as seen in Fig. 1.

[043] Fig. 3 is a detail view of a cross section of the generator/motor as seen in Figs. 1 and 2.

[044] Fig. 4 is an exploded view of the generator/motor as seen in Figs. 1 to 3.

[045] Fig. 5 is another exploded view of the generator/motor as seen in Figs. 1 to 4.

[046] Fig. 6 is a cross-sectional view of another embodiment of a generator/motor having vertical axis of a rotation.

[047] As seen in Figs. 1 to 5, the motor/generator comprises a rotor assembly (2) comprising a central rotor axis (2) which has grooves machined on the rotor shaft. On these grooves slide the rotor covers (11). The rotor covers (11) contain within them the whole rotor assembly except for the current collection assembly. Within the rotor covers (11) are located the rotor main magnetic core (1) and the second part of the main magnetic core (13) which serves as the path that closes the magnetic field lines from the pole pairs that are located within the main magnetic core (1). Both cores (1; 13) comprises involute slots (1A; 13A) and involute protrusions (1B;13B). Also within the main magnetic core (1) are located the excitation coils (17) that are wrapped around or mounted on the involute protrusions (IB) located in the main magnetic core (1). The excitation coils (17) fill the empty space that is within the involute slots (1A) within the main magnetic core (1). For each two involute protrusions (IB) there is a single excitation coil (17) forming a pole pair, where the field lines are pointing in one direction within the protrusion that houses the coil and looping back through the second part of the main magnetic core (13) through the neighboring protrusion where the field lines are in the opposite direction.

[048] Between the two parts of the rotor main magnetic core (1) and (13) the involute slotted Faraday disc is located. Further in the text referred to as an involute slotted conductive disc (51; 71). There are two such discs within the rotor magnetic core, namely the first disc (51) and the second disc (71). Because it is technically preferred that the current generated be collected at a smaller radius, near the rotor axis (2) of both discs (51; 71) are used as one serves as the current path from center to periphery while the other serves as a return path. Both discs (51; 71) participate in current generation so by this method the output voltage is doubled as compared to a single classical Faraday disc. The slotted conductive discs (51;71) are either laminated or other means of electrical isolation/heat conduction are used to shield them from the main magnetic core parts. Due to the flat large surface space of the slotted conductive discs (51; 71) against the rotor magnetic core parts (1; 13) there is good heat conduction. This heat is further passed onto the rotor covers (11) where with the help of grooves on the plates the heat is easily dissipated when the rotor is spinning. The rotor covers (11) can be made to function as large fans. On one of the rotor covers (11) is attached a circular support (7) which serves to attach and hold the rotating liquid metal contact assembly (40) to the rotor structure. The rotating liquid metal contact assembly (40) comprises screws/rivets as the connecting members (14) that hold it together structurally are made such that they have an empty middle whereby they can be attached via other screws to the circular support (7). Please see Figs 1 to 5.

[049] The current collection device is the most complicated structure within this generator due to the peculiar physical laws that govern the way it works which we discussed earlier. The current collection device is referred to as the “rotating liquid metal contact assembly” (40). This contact assembly can be thought of as a motor within a motor, or as the separator within a ball bearing, where we know the separator rotates with a different RPM than that of the shaft the bearing holds. The output voltage of the generator is dependent on the relative speeds between the two loops, namely the rotating loop formed by the generator discs and the stationary loop formed by the disc current collector contacts which in the classical model are stationary brushes. In the classical generator mentioned earlier the brushes are stationary and fixed so one cannot vary their speed relative to the disc. In the proposed motor/generator the current collector parts are free to move with respect to the slotted discs (51;71) contained within the rotor main body. Thanks to this feature the output voltage of the generator can be varied even more by either keeping the current collection contacts stationary while the rotor rotates or rotating the contacts in opposite direction to the rotor main body which would result in an increased voltage and power output.

[050] The rotating liquid metal contact assembly (40) is itself made from three individual parts, namely the main body (6) onto which two isolated electrodes are attached (20; 21), an end body (5), a separator (18) for separating the liquid metal onto each electrode while rotating. On the inner diameter of the main body (40) a toroidal stator ring (12) is located which is the stator for the rotor (4) located within the liquid metal contact assembly main body (40). The rotor (4) has a permanent magnet ring (3) attached to its inner side forming a rotor with the stator (12) which is analogous to a permanent magnet BLDC motor. The rotor (4) has two toroidal rotor electrodes (19) attached to it. The electrodes are shunted (short circuited) after given fixed intervals with a connection that is made between them and through the rotor body (4) which itself is made from a nonconductive material. The toroidal stator ring (12) is a three phase stator like that of an ordinary BLDC motor, it is electrically connected to the pickup ring (8) which is an identical stator like ring that serves as a power pickup/transfer device from the stationary frame to the rotary frame. The pickup ring (8) is spaced with an air gap against the stationary stator ring (10) located on a stator (9). The stationary stator ring (10) and pickup ring (8) can be though as a power transfer mechanism from the stationary frame to the rotary frame. As this power is now fed to the rotary frame it travels from the pickup ring (8) into the toroidal stator ring (12) located within the liquid metal contact assembly main body (40). By this means the speed of the rotor (4) located inside the main body (40) from a stationary frame may be controlled. If the whole generator rotor is moving at speed X then by applying a DC potential to the stator ring (10) we will induce power into the pickup ring (8) and at the same time into the toroidal stator ring (12) because the pickup ring (8) and toroidal stator ring (12) are electrically connected and identical in coil layout. This induced current will then create pole pairs within the toroidal stator ring (12) which will then latch on to the pole pairs of the permanent magnet ring (3) on the rotor (4) dragging the whole rotor structure (4) with it. As the rotor speed increases the induced current also increases and the rotor (4) holding becomes stronger. This additional step of power transfer to the rotor (4) via (8) and (10) is necessary because without it the required air gap between a stationary stator and rotary rotor would be too large to be practical. See Figs 1 to 5.

[051] If on the other hand one wants to make the rotor (4) within the main body (40) turn in the opposite direction than that of the rotor of the generator in order to increase output voltage, then an AC variable frequency signal can be applied to the stationary stator (10).

[052] At first as the generator rotor is stationary the liquid metal (mercury for example) (M) rests on the lower side of the rotating liquid metal contact assembly (40), as the rotor starts to rotate, even at low RPM (100 RPM for example) the liquid metal (mercury) (M) is spread out across the outer edge of the rotating liquid metal contact assembly (40) inner channel. This happens because most known liquid metals, especially mercury is very dense and heavy and is dragged along the channel while at the same time pressed against the channel wall due to centripetal force.

[053] The electrodes (20; 21) within the channel or volume (61) of the rotating liquid metal contact assembly (40) have small grooves on their surface which helps to drag the metal along the electrodes. As this process happens the separator (18) maintains that the two now separated streams of liquid metal don’t touch each other directly. The toroidal electrodes (19) that are attached to the rotor (4) float atop the spread out liquid metal stream, so the liquid metal also serves as a bearing mechanism for the rotor (4). At startup the rotor (4) is allowed to turn together with the rotating liquid metal contact assembly itself (40), then as the liquid metal has spread out evenly within the channel, a DC potential is applied to the stationary stator ring (10) and the rotor (4) slowly stopped in place with respect to the generator rotor itself. As the rotor (4) now turns against the channel it is immersed in it further helps to spread out and even out the thin liquid metal layer. Due to the low surface adhesion of liquid metals like mercury, the rotor (4) feels very little drag/friction while turning at a different speed with respect to the rest of the channel. Due to the fact that the liquid metal (M) experiences a constant centripetal force, even as it is being pushed away by the rotor (4) toroidal electrodes (19) it constantly moves back and pushes against the electrodes (19) itself, maintaining a constant contact. Although as said mercury has very low adhesion to surfaces it maintains good contact with the electrodes (20;21) of the rotating liquid metal contact assembly (40) because of centripetal force experienced by mercury while at the same time it also serves as a very low friction bearing to the toroidal electrodes (19) of the rotor (4). The whole rotating liquid metal contact assembly (40) is hermetically sealed which permits the use of such metals as mercury within it, as mercury has better electrical and mechanical properties than other liquid metals. The rotating liquid metal contact assembly (40) is made from nonconductive materials, except for the conductive parts like the main electrodes (20;21) toroidal rotor electrodes (19) and liquid metal contained inside. In order to endure liquid metals like mercury and others the electrodes are either galvanized with a coating that is nonreactive with the liquid metal or made from a metal that does not react with the liquid metal. The maximum speed difference between the rotor (4) and the channel of the rotating liquid metal contact assembly (40) is not known and should be investigated by practical experiment, but based on theoretical models and known physics it should be substantial enough to allow not only stationary working mode which would be analogous to a stationary brush on a classical Faraday disc but also allow for reverse rotation which would increase the total speed difference between the two electrical loops of the generator and thereby increase the output voltage/power. The use of a hermetically sealed rotating liquid metal contact assembly (40) like the one proposed here results in a contact resistance which is almost equal to the internal resistance of the slotted conductive discs (51 ;71) themselves which results in a very efficient generator design and the ability to have very large currents through the generator. See Figs 1 to 5.

[054] In another embodiment of the invention, the motor/generator has vertically positioned rotor shaft (2). See Fig. 6. In the vertical position everything contained within the generator rotor main body which is held in place by the rotor covers (11) is identical to the horizontal case. The only part that differs slightly is the rotating liquid metal contact assembly (40). This is due to the effects on gravity on the liquid metal. The basic function of the rotating liquid metal contact assembly (40) as well as its parts are the same in the vertical position as in the horizontal position, there are only slight differences to the shape of the electrodes (20;21) and the elimination of the separator (18). The function of the separator is now done by one of the two electrodes which also functions as a fluid separator. In fact in the vertical axis position case the rotating liquid metal contact assembly (40) function is even better, because due to gravity the liquid metal is always spread out evenly across the whole surface of the electrodes around the whole assembly, which allows the rotor (4) to always float atop the liquid metal. As the assembly starts to rotate due to centripetal force the liquid metal would then move and form triangular circular rings pressed against the corners of both electrodes, the rotor toroidal electrodes would then push against this and the same function would result.

[055] It is also possible to build a generator/motor and put many such rotor assemblies on one rotor.

[056] Each fully equipped rotor has two electrical terminals both located within the inner diameter of the slotted conductive discs (51 ;71) inside the rotor cover plates (11), by the use of holes or slots within the rotor cover plates (11) it is possible to electrically wire either a single such rotor or many parallel rotors together in either a parallel or series connection depending on the application.

[057] The overall current generated on the rotor can be then collected by two means. Either by using a rotating transformer located adjacent to the rotors on the same shaft or by using a liquid metal current collection device.

[058] In case only AC operation is necessary and there is enough free space one can use a rotational transformer, if also DC as well as AC operation is needed to use the full capability of the generator/motor one can use liquid metal contacts.

[059] It is possible to use an assembly of rotating contacts located within a cavity sealed by ordinary seals or ferrofluid seals where the nontoxic eutectic of Ga In Sn can be used as means of transferring current from the rotational frame to the stationary one.

[060] Another rotating contact must be used to deliver the excitation coil current to the rotor. Here I propose the use of ordinary graphite brushes and copper sliding contacts, because the current necessary for the coils is not large and within the range that is normally used in industrial products. Further if one assembles multiple parallel rotor assemblies on a single rotor, one can use one of the assemblies as the generator for the excitation coil current for the rest of the rotor assemblies. [061] The excitation coils within a given rotor assembly are normally wired all in parallel which means they have very low inductance which is good in case for pulse operation of the generator, but the wiring of the excitation coils can be changed if necessary for certain applications.

[062] The generator can also be wired in such a way that it is self excited by wiring the excitation coils either in parallel or series with the generator slotted conductive discs.

[063] Also by using capacitors in the output of the generator and with various internal wiring possibilities, the generator can be made to function as an oscillator. It can function as a LC tank circuit either series or parallel.

[064] Therefore, this generator/motor is capable of flexible operation within wide operation modes within a wide array of fields both within the industry and outside it in special applications like military hardware, rail gun technology etc.

[065] In case of pulse operation, the output pulse rise time would be dependent on the total impedance of the machine in question which can be changed by changing the connection types within the generator and its geometry.

[066] If the generator uses high quality electrical steel laminations for its rotor, it can sustain both DC operation as well as AC operation from 1 Hz to about 25 Khz or more depending on the core metal properties used in the main magnetic cores (1 ;13) of the generator.

[067] It is possible to have an even higher frequency output up to couple of Mhz by using ferrite or other high frequency compliant magnetic materials for the main magnetic cores of the generator.

[068] While the invention may be susceptible to various modifications and alternative forms, specific embodiments of which have been shown by way of example in the figures and have been described in detail herein, it should be understood that the invention is not intended to be limited to the particular forms disclosed. Rather, the invention includes all modifications, equivalents, and alternatives falling within the scope of the invention as defined by the following claims.

[0691 List of references

1 - a first part of a rotor main magnetic core;

1A - an involute slot of a first part of a rotor main magnetic core;

IB - an involute protrusion of a first part of a rotor main magnetic core;

2 - a rotor shaft;

3 - a permanent magnet ring;

4 - a rotor;

5 - an end body of a rotating liquid metal contact assembly;

6 - a main body of a rotating liquid metal contact assembly;

7 - a support;

8 - a pickup ring;

9 - a stator;

10 - a stationary stator ring;

11 - a rotor cover;

12 - a toroidal stator ring;

13 - a second part of a rotor main magnetic core;

13 A - an involute slot of a second part of a rotor main magnetic core;

13B - an involute protrusion of a second part of a rotor main magnetic core;

14 - a connecting member;

17 - an excitation coil;

18 - a separator;

19 - a rotor electrode;

20 - a contact assembly electrode;

21 - a contact assembly electrode;

30 - a rotor assembly;

40 - a rotating liquid metal contact assembly;

51 - a first slotted conductive disc;

61 - a hermetically sealed volume;

71 - a second slotted conductive disc; and

M - a liquid metal.