Patent Description:
Conventional, axial air gap brushless motors with layered disk stators are known, such as <CIT>. That patent discloses a stator winding that uses wires interconnected in a wave or lap configuration. Such motors are relatively large and difficult to manufacture. Axial field electric devices that use PCB stators also are known, such as <CIT>, <CIT> and <CIT>. However, some of these designs are complicated, relatively expensive and they are not modular. Thus, improvements in cost-effective axial field rotary energy devices continue to be of interest. Document <CIT> discloses a related machine.

The above identified objects are solved by the features of the independent claim. Advantageous embodiments can be derived from the respective dependent claims.

The foregoing and other objects and advantages of these embodiments will be apparent to those of ordinary skill in the art in view of the following detailed description, taken in conjunction with the appended claims and the accompanying drawings.

So that the manner in which the features and advantages of the embodiments are attained and can be understood in more detail, a more particular description can be had by reference to the embodiments thereof that are illustrated in the appended drawings. However, the drawings illustrate only some embodiments and therefore are not to be considered limiting in scope as there can be other equally effective embodiments.

<FIG> depict various views of an embodiment of a device <NUM> comprising an axial field rotary energy device (AFRED). Depending on the application, device <NUM> can comprise a motor that converts electrical energy to mechanical power, or a generator that converts mechanical power to electrical energy.

Embodiments of device <NUM> include at least one rotor <NUM> comprising an axis <NUM> of rotation and a magnet (i.e., at least one magnet <NUM>). A plurality of magnets <NUM> are shown in the embodiment of <FIG>. Each magnet <NUM> can include at least one magnet pole.

Device <NUM> also includes a stator <NUM> that is coaxial with the rotor <NUM>. Rotor <NUM> can be coupled on a shaft <NUM> and with other hardware, such as one or more of the following items: a mount plate, fastener, washer, bearing, spacer or alignment element. Embodiments of the stator <NUM> includes a single unitary panel, such as the printed circuit board (PCB) <NUM> shown in <FIG>. PCB <NUM> includes at least one PCB layer <NUM>. For example, certain embodiments described herein include twelve PCB layers <NUM>. PCB layers <NUM> can be parallel and spaced apart in the axial direction. Each PCB layer <NUM> can include at least one conductive trace <NUM>. Each trace <NUM> is a separate conductive feature formed on a given PCB layer <NUM>. For example, eight traces <NUM> are shown in <FIG>. Traces <NUM> can be configured in a desired pattern, such as the coils illustrated in <FIG>.

<FIG> depicts an embodiment of one PCB layer <NUM> within a twelve-layer PCB <NUM>. The other eleven PCB layers are similar, with differences described below in regards to subsequent figures. On the illustrated PCB layer <NUM>, each trace <NUM> (forming a single coil) includes a first terminal <NUM> at the outer edge of the coil, and a second terminal <NUM> in the center of coil. Traces <NUM> are connected to other traces <NUM> using vias <NUM>. A first set of vias <NUM> is disposed adjacent to the first terminal <NUM> at the outer edge of each coil, and a second set of vias <NUM> is disposed adjacent to the second terminal in the center of each coil. In this embodiment, traces <NUM> on the illustrated PCB layer <NUM> are not directly connected to an adjacent trace <NUM> on this illustrated PCB layer <NUM>, but rather are each directly connected to a corresponding trace <NUM> on another PCB layer <NUM>, as more thoroughly explained in regards to <FIG> and <FIG>.

In this embodiment, each trace <NUM> is continuous and uninterrupted from its first terminal <NUM> to its second terminal <NUM>, and connections to such trace <NUM> are made only to the first and second terminals <NUM>, <NUM>. Each trace <NUM> includes no other terminals for electrical connections. In other words, each trace <NUM> can be seamlessly continuous with no other electrical connections, including no additional vias <NUM>, between the first and second terminals <NUM>, <NUM>. Also shown in <FIG>, the width of a given trace <NUM> can be not uniform. For example width <NUM> corresponding to an outer trace corner can be wider than width <NUM> corresponding to an inner trace corner. Gap <NUM> between adjacent concentric trace portions forming a single coil can be the same or different than the gap <NUM> between adjacent traces (i.e., separate coils). In some embodiments, a given trace can comprise an outer width that is adjacent an outer diameter of the PCB and in a plane that is perpendicular to the axis <NUM>, and an inner width that is adjacent an inner diameter of the PCB and in the plane. In some embodiments the outer width can be greater than the inner width. In some embodiments a given trace can comprise inner and outer opposing edges that are not parallel to each other.

<FIG> depicts an embodiment of a twelve-layer PCB <NUM> incorporating the PCB layer <NUM> shown in <FIG>. Each of the twelve PCB layers <NUM> are closely spaced and form a "sandwich" of PCB layers <NUM>, labeled as <NUM>-<NUM>. On the uppermost PCB layer <NUM>, a first trace <NUM> (also described herein as "coil <NUM>") is shown whose first terminal <NUM> is coupled to an external terminal <NUM> for the device <NUM>. On the lowermost PCB layer <NUM>, a trace <NUM> is shown whose first terminal <NUM> is coupled to an external terminal <NUM> for the device <NUM>. In this embodiment, there are eight traces <NUM> (coils) on each of twelve PCB layers <NUM>-<NUM>. These traces are coupled together (as more fully described below) such that current flowing into the external terminal <NUM> will flow through the ninety-six coils, then flow out the external terminal <NUM> (or conversely flow into external terminal <NUM> and out external terminal <NUM>). In this embodiment, only one trace <NUM> (e.g., coil <NUM>) is coupled to the external terminal <NUM> for the device <NUM>, and only one trace <NUM> (e.g., coil <NUM>) is coupled to the external terminal <NUM> for the device <NUM>. For a motor, both external terminals <NUM>, <NUM> are input terminals and, for a generator, both external terminals <NUM>, <NUM> are output terminals. As can be appreciated in this embodiment, each PCB layer includes a plurality of coils that are co-planar and angularly and symmetrically spaced apart from each other about the axis, and the coils in adjacent PCB layers, relative to the axis, are circumferentially aligned with each other relative to the axis to define symmetric stacks of coils in the axial direction.

<FIG> is an exploded view of a portion of the twelve-layer PCB <NUM> shown in <FIG>, which is labeled to better illustrate how the coils are coupled together by vias <NUM>, <NUM>, and thus to better illustrate how current flows into the external terminal <NUM>, through the ninety-six coils, then flows out the external terminal <NUM>. Assume that input current <NUM> flows into external terminal <NUM>. This current flows "spirally" around coil <NUM> (on PCB layer <NUM>) as current <NUM> and <NUM>, and reaches the second terminal <NUM> of coil <NUM>. A via <NUM> couples the second terminal <NUM> of coil <NUM> to the second terminal of the corresponding coil <NUM> on PCB layer <NUM> directly below coil <NUM>. Thus, the current flows through via <NUM> as current <NUM>, then flows spirally around coil <NUM> as current <NUM> until it reaches the first terminal <NUM> for coil <NUM>. A via <NUM> couples the first terminal <NUM> of coil <NUM> to the first terminal of coil <NUM> on PCB layer <NUM>, which is adjacent to the first coil <NUM>. In this embodiment, the traces <NUM> on the first PCB layer <NUM> are generally reversed (mirror-imaged) relative to those on the second PCB layer <NUM>, so that the via <NUM> overlaps with both "tabs" on the respective second terminal <NUM> of coils <NUM> and <NUM>, and likewise so that the via <NUM> overlaps with both "tabs" on the respective first terminal <NUM> of coils <NUM> and <NUM>, as is more thoroughly described below in regards to subsequent figures. Thus, the current flows through via <NUM> as current <NUM> to the first terminal <NUM> of coil <NUM> on PCB layer <NUM>.

From this terminal, the current flows through coils <NUM> and <NUM> similarly to that described for coils <NUM> and <NUM>. For example, the current flows around coil <NUM> (on PCB layer <NUM>) as current <NUM> and <NUM> to the second terminal <NUM> of coil <NUM>, flows through via <NUM> as current <NUM> to the second terminal <NUM> of coil <NUM>, then flows as current <NUM> and <NUM> around coil <NUM> until it reaches the first terminal <NUM> for coil <NUM>. As before, a via <NUM> couples the first terminal <NUM> of coil <NUM> to the first terminal <NUM> of coil <NUM> on PCB layer <NUM>, which is adjacent to coil <NUM>. This coupling configuration is replicated for all remaining traces <NUM> on the upper two PCB layers <NUM>, <NUM>, and the current flows through these remaining traces <NUM> until it reaches the last coil <NUM> on PCB layer <NUM>. The current, after having already flowed through all sixteen coils on the upper two PCB layers <NUM>, <NUM>, is now directed to the next PCB layer <NUM>. Specifically, a via <NUM> couples the first terminal <NUM> of coil <NUM> to the first terminal of coil <NUM> on PCB layer <NUM>, which is directly below coils <NUM> and <NUM>. In this embodiment there is only one such via <NUM> coupling a coil on PCB layer <NUM> to a coil on PCB layer <NUM>. Conversely, there are fifteen such vias <NUM> coupling together coils on PCB layers <NUM>, <NUM>. In this embodiment such coupling occurs only at the first and second terminals <NUM>, <NUM> of the coils.

The vias <NUM> between the third and fourth PCB layers <NUM>, <NUM> are configured identically as those between the first and second PCB layers <NUM>, <NUM> described above, and thus the via configuration and the corresponding current flow need not be repeated. This continues downward through the PCB layer "sandwich" until reaching the lowermost PCB layer <NUM> (not shown here). As described above, the first terminal <NUM> for trace (coil) <NUM> is coupled to the external terminal <NUM>. Consequently, the current that flows inward through external terminal <NUM>, after flowing through all ninety-six coils, flows outward through external terminal <NUM>.

<FIG> is an enlarged view of a group of vias <NUM> shown in <FIG>. This via group is adjacent to the respective second terminal <NUM> for each of a group of vertically aligned coils <NUM>-<NUM> on each of the twelve PCB layers <NUM>-<NUM>. As noted above, the traces <NUM> on the second PCB layer <NUM> are generally reversed (mirror-imaged) relative to those on the first PCB layer <NUM>, so that the via <NUM> overlaps with both "tabs" on the respective second terminal <NUM> of these vertically adjacent coils. As shown in <FIG>, on coil <NUM> (first layer, eighth coil) the second terminal <NUM> includes a tab extending to the side of the trace. In mirror-image fashion, on coil <NUM> (second layer, eighth coil) the second terminal <NUM> includes a tab extending in the opposite direction to the side of the trace, so that these two tabs overlap. A via <NUM> couples together these two overlapping tabs. In like manner, since the embodiment shown includes <NUM> PCB layers <NUM>, each of five additional vias <NUM> respectively couples overlapping terminals <NUM> and <NUM>, overlapping terminals <NUM> and <NUM>, overlapping terminals <NUM> and <NUM>, overlapping terminals <NUM> and <NUM>, and overlapping terminals <NUM> and <NUM>.

<FIG> shows two of these vias <NUM> in an exploded format. Terminal <NUM> of coil <NUM> overlaps with terminal <NUM> of coil <NUM>, and are coupled together by a first via <NUM>. Terminal <NUM> of coil <NUM> overlaps with terminal <NUM> of coil <NUM>, and are coupled together by a second via <NUM>. As can be clearly appreciated in the figures, these pairs of overlapping tabs, together with their corresponding vias <NUM>, are staggered in a radial direction so that such vias <NUM> can be implemented using plated through-hole vias. Alternatively, such vias <NUM> can be implemented as buried vias, in which case the vias need not be staggered, but rather can be vertically aligned.

<FIG> is an enlarged view of a group of vias <NUM> also shown in <FIG>. In this embodiment, these vias <NUM> are disposed in the gap between one specific adjacent pair of vertically aligned coils <NUM> (e.g., between uppermost layer coil <NUM> and <NUM>), whereas vias <NUM> are disposed in the other gaps between other adjacent pairs of vertically aligned coils <NUM>. In this figure, the vias <NUM> are shown as plated through-hole vias. Vias <NUM>, <NUM> overlap with both "tabs" on the respective first terminal <NUM> of the corresponding coils. Vias <NUM> couple horizontally adjacent coils on vertically adjacent layers, while vias <NUM> couple horizontally aligned coils on vertically adjacent layers, both as shown in <FIG>. There are only five vias <NUM> shown in this embodiment because the first terminal <NUM> on the uppermost coil <NUM> is coupled to the external terminal <NUM>, and the first terminal <NUM> of coil <NUM> on the lowermost PCB layer <NUM> is coupled to the external terminal <NUM>, leaving only <NUM> PCB layers (<NUM>-<NUM>) having coils whose respective first terminals <NUM> are coupled together in pairs. For example, the innermost via <NUM> couples a respective coil on PCB layer <NUM> to a respective coil on PCB layer <NUM>.

In various embodiments, each trace <NUM> can be electrically coupled to another trace <NUM> with at least one via <NUM>. In the example of <FIG>, each PCB layer <NUM> has eight traces <NUM> and only one via <NUM> between traces <NUM>. In some embodiments, every trace <NUM> is electrically coupled to another trace <NUM>. Together, two traces <NUM> define a trace pair <NUM>. In <FIG>, there are twelve PCB layers <NUM>-<NUM>, and there are six trace pairs <NUM>-<NUM>.

Each trace pair <NUM> can be electrically coupled to another trace pair <NUM> with at least one other via <NUM> (e.g., such as only one via <NUM>). In some versions, the traces <NUM> (e.g., coils) in each trace pair <NUM> (e.g., coil pair) can be located on different PCB layers <NUM>, as shown in <FIG>. In other versions, however, the traces <NUM> in each trace pair <NUM> can be co-planar and located on the same PCB layer <NUM>.

In some embodiments, at least two of the traces <NUM> (e.g., coils) are electrically coupled in series. In other versions, at least two of the traces <NUM> (e.g., coils) are electrically coupled in parallel. In still other versions, at least two of the traces <NUM> are electrically coupled in parallel, and at least two other traces <NUM> are electrically coupled in series.

Embodiments of the device <NUM> can include at least two of the trace pairs <NUM> electrically coupled in parallel. In other versions, at least two of the trace pairs <NUM> are electrically coupled in series. In still other versions, at least two of the trace pairs <NUM> are electrically coupled in parallel, and at least two other trace pairs <NUM> are electrically coupled in series.

As depicted in <FIG> and <FIG>, each PCB layer <NUM> (only the top PCB layer <NUM> is shown in the top <NUM> views) comprises a PCB layer surface area (LSA) that is the total surface area (TSA) of the entire (top) surface of the PCB <NUM>. The TSA does not include the holes in the PCB <NUM>, such as the center hole and the mounting holes that are illustrated. The one or more traces <NUM> (eight coils shown in <FIG>) on the PCB layer <NUM> can comprise a coils surface area (CSA). The CSA includes the entire footprints of the coils (i.e., within their perimeters), not just their "copper surface area". The CSA can be in a range of at least about <NUM>% of the PCB layer surface area, such as at least about <NUM>%, at least about <NUM>%, at least about <NUM>%, at least about <NUM>%, at least about <NUM>%, at least about <NUM>%, at least about <NUM>%, at least about <NUM>%, at least about <NUM>%, at least about <NUM>%, or even at least about <NUM>% of the PCB layer surface area. In other embodiments, the coils surface area can be not greater than <NUM>% of the PCB layer surface area, such as not greater than about <NUM>%, not greater than about <NUM>%, not greater than about <NUM>%, not greater than about <NUM>%, not greater than about <NUM>%, or even not greater than about <NUM>% of the PCB layer surface area. In other embodiments, the coils surface area can be in a range between any of these values.

The CSA also can be calculated with respect to any sensors or circuitry (such as IOT elements) on or in the PCB. The IOT elements can be limited to not greater than <NUM>% of the TSA. Additionally, the IOT elements can be embedded within the CSA or embedded in at least part of the TSA this is not included in the CSA.

The total area of each trace that forms a coil (i.e., including the conductive traces, but cannot necessarily include the spaces between the conductive traces) can be viewed as a coil surface area. It is believed that performance of the device <NUM> is improved with increasing aggregate coil surface area, relative to the underlying PCB layer surface area on which the coil(s) is formed.

In some embodiments (<FIG>), the device <NUM> can comprise a stator <NUM> comprising a single electrical phase. Versions of the stator <NUM> can consist of a single electrical phase. Each PCB layer <NUM> can comprise a plurality of coils that are co-planar and symmetrically spaced apart about the axis <NUM> (<FIG> and <FIG>). In one example, each coil consists of a single electrical phase.

<FIG> depicts an embodiment of the stator <NUM> comprising at least two electrical phases (e.g., three phases shown). Each PCB layer <NUM> can include a plurality of coils (such as traces <NUM>) as shown for each electrical phase. For example, <FIG> illustrates coils corresponding to three phases A, B and C. The coils for each electrical phase A, B, C can be angularly offset from each other with respect to the axis <NUM> (<FIG> and <FIG>) within each PCB layer <NUM> to define a desired phase angle shift between the electrical phases A, B, C. In <FIG>, there are nine traces <NUM> on each PCB layer <NUM>. Since the embodiment of stator <NUM> in <FIG> is three phases, each trace <NUM> in phase A is <NUM> electrical degrees apart from other traces <NUM> for phase A, and <NUM> electrical degrees apart from adjacent traces <NUM> for phases B and C. The traces <NUM> for phase B (relative to phases A and C) and for phase C (relative top phases A and B) are spaced likewise.

In some embodiments, each coil (e.g., trace <NUM>) can consist of a single electrical phase. Alternatively, the coils can be configured to enable the stator <NUM> with two or more electrical phases (e.g., three phases shown in <FIG>).

The example in <FIG> is a simplified view of only some interior components of an embodiment of device <NUM>. Each of the magnets <NUM> can include a magnet radial edge or element <NUM> (also referred to herein as a "magnet radial edge <NUM>"), and each of the traces <NUM> can include a trace radial edge or element <NUM> (also referred to herein as a "coil radial edge <NUM>"). The magnets <NUM> are part of the rotor <NUM> (<FIG>) and rotate about the axis <NUM> with respect to the stationary stator <NUM>. When radial edge portions of the magnets <NUM> and the traces <NUM> rotationally align relative to the axis during operation of the device <NUM>, at least portions of the radial elements <NUM>, <NUM> can be skewed (i.e., not parallel) relative to each other. In some embodiments, when radial edge portions of the magnets and coils rotationally align relative to the axis, the magnet radial edges and coil radial edges are not parallel and are angularly skewed relative to each other. <FIG> illustrates a rotation position of the magnets <NUM> for which a radial edge portion of the magnet <NUM> (i.e., the magnet radial edge <NUM> nearing the corner of the magnet <NUM>) is rotationally aligned with a radial edge portion of the coil <NUM>, and which illustrates the skew between the magnet radial edge <NUM> and the coil radial edge <NUM>. In one version, the radial elements <NUM>, <NUM> can be leading radial edges or trailing radial edges of the magnets <NUM> and traces <NUM>. In another example, the magnet and trace radial edges or elements <NUM>, <NUM> can be linear as shown, and no portions of the magnet and trace radial elements <NUM>, <NUM> are parallel when the magnets <NUM> and traces <NUM> rotationally align in the axial direction.

In some embodiments, the magnet radial elements <NUM> can be angularly skewed relative to the trace radial elements <NUM>, and the angular skew can be greater than <NUM> degrees, such as greater than <NUM> degrees, at least about <NUM> degree, at least about <NUM> degrees, at least about <NUM> degrees, at least about <NUM> degrees, or even at least about <NUM> degrees. In other versions, the angular skew can be not greater than about <NUM> degrees, such as not greater than about <NUM> degrees, not greater than about <NUM> degrees, not greater than about <NUM> degrees, not greater than about <NUM> degrees, not greater than about <NUM> degrees, not greater than about <NUM> degrees, or even not greater than about <NUM> degrees. Alternatively, the angular skew can be in a range between any of these values.

In an alternate embodiment, at least portions of the radial elements <NUM>, <NUM> can be parallel to each other during rotational alignment.

Some embodiments of an axial field rotary energy device can be configured in a manner similar to that described for device <NUM>, including assembly hardware, except that the stator can be configured somewhat differently. For example, <FIG> depict a simplified version of a device <NUM> with only some elements shown for ease of understanding. Device <NUM> includes a stator <NUM> that is coaxial with a rotor <NUM>. Optionally, each rotor <NUM> can include one or more slits or slots <NUM> (<FIG>) that extend therethrough. In some versions, the slots <NUM> are angled with respect to axis <NUM> (<FIG>) and, thus, are not merely vertical. The angles of the slots <NUM> can be provided at constant slopes, and can facilitate a cooling air flow within the device <NUM>. Slots <NUM> can enable air flow to be pulled or pushed through and/or around the rotors <NUM> and effectively cool the stators <NUM>. Additional slots can be provided in rotor spacers, such as rotor spacer <NUM> (<FIG>), particularly in embodiments having a plurality of stator segments, and particularly in embodiments having an inner diameter R-INT of the stator assembly (<FIG>) irrespective of the outer diameter R-EXT.

Rather than comprising a single panel PCB <NUM> as described for stator <NUM>, the stator <NUM> can include a plurality of stator segments <NUM>, each of which can be a separate PCB <NUM>. The stator segments <NUM> can be coupled together, such as mechanically and electrically coupled together. Each stator segment <NUM> can include a printed circuit board (PCB) having one or more PCB layers <NUM> (<FIG>) as described elsewhere herein. In one example, each PCB <NUM> can have an even number of PCB layers <NUM>. In an alternate embodiment, the PCB <NUM> can have an odd number of PCB layers <NUM>.

Embodiments of the stator segments <NUM> can comprise or correspond to only one electrical phase. Moreover, the stator <NUM> of device <NUM> can consist of or correspond to only one electrical phase. In other versions, the stator <NUM> can comprise or correspond to a plurality of electrical phases. As shown in <FIG>, each stator segment <NUM> includes at least one PCB layer <NUM> having at least one conductive trace <NUM>, such as the coil illustrated. In some versions (<FIG>), each stator segment <NUM> can have at least one PCB layer <NUM> having a plurality of traces <NUM> (e.g., coils) that are co-planar and angularly spaced apart from each other relative to the axis <NUM> (<FIG> and <FIG>). In one example, each trace <NUM> can comprise a single electrical phase. In another version, each stator segment <NUM> can include a plurality of PCB layers <NUM>, each of which can be configured to correspond to only one electrical phase. In some versions, each PCB layer <NUM> on each stator segment <NUM> can include a plurality of axially co-planar traces <NUM> that are configured to correspond to only one electrical phase.

In some embodiments (<FIG>), each PCB layer <NUM> can include at least one radial trace <NUM> that extends from about an inner diameter (ID) of the PCB <NUM> to about an outer diameter (OD) of the PCB <NUM>. In one example, each PCB layer <NUM> include a trace <NUM> that is continuous from an outermost trace portion <NUM> to a concentric innermost trace portion <NUM>. The traces <NUM> can include radial traces <NUM> having linear sides and chamfered comers <NUM>. The linear sides of the radial traces can be tapered, having an increasing trace width with increasing radial distance. Inner end turn traces <NUM> and outer end turn traces <NUM> extend between the radial traces <NUM> to form a concentric coil.

Regarding the tapered traces and coils, the tapers can improve the amount of conductive material (e.g., copper) that can be included in a PCB stator. Since many motors and generators comprise a round shape, the coils can be generally circular and, to fit together collectively on a stator, the perimeters of the coils can be somewhat pie-slice-shaped or triangular. In some versions, the coils can have a same width in a plane perpendicular to the axis, and in other versions the coils can be tapered to increase the conductor (e.g., copper) densities of the coils. Improving copper density can have significant value to reduce electrical resistance, I2R losses and heat generation, and increase the ability to carry a higher electrical current to provide a machine with higher efficiency.

In another version, each PCB layer <NUM> can include only linear traces <NUM> (<FIG>). Linear traces <NUM> can be continuous from an outermost trace <NUM> to a concentric innermost trace <NUM>. In one example, no trace <NUM> of the PCB layers <NUM> is non-linear. However, embodiments of the only linear traces <NUM> can include turns, such as, for example, rounded comers or chamfered comers. As used herein, a "turn" includes a trace portion connecting a radial trace to an end turn trace. In other embodiments, the PCB layer <NUM> can include one or more non-linear, such as curvilinear traces.

As noted herein, the PCB <NUM> can include a plurality of PCB layers <NUM> that are spaced apart from each other in the axial direction. The PCB layers <NUM> can comprise layer pairs <NUM> (<FIG>; see pairs <NUM> to <NUM>). Each layer pair <NUM> can be defined as two PCB layers that are electrically coupled together. In one version, at least one of the PCB layers <NUM> is electrically coupled to another PCB layer <NUM> in series or in parallel. In another version, at least one layer pair <NUM> is electrically coupled to another layer pair <NUM> in series or in parallel. In one embodiment, at least one of the layer pairs <NUM> comprises two PCB layers <NUM> and <NUM> that are axially adjacent to each other. In another embodiment, at least one of the layer pairs <NUM> comprises two PCB layers <NUM> and <NUM> that are not axially adjacent to each other. Similarly, at least one of the layer pairs <NUM> can be axially adjacent to the layer pair <NUM> to which said at least one of the layer pairs is electrically coupled. Conversely, at least one of the layer pairs <NUM> can be not axially adjacent to the layer pair <NUM> to which said at least one of the layer pairs <NUM> is electrically coupled.

Embodiments of the PCB layers <NUM> can include at least one layer set <NUM> (<FIG>). For example, layer set <NUM> can include a first layer <NUM>, a second layer <NUM>, a third layer <NUM> and a fourth layer <NUM>. In some versions, a first via <NUM> can couple the first layer <NUM> to the third layer <NUM>, a second via <NUM> can couple the third layer <NUM> to the second layer <NUM>, and a third via <NUM> can couple the second layer <NUM> to the fourth layer <NUM>. In one example, the first, second and third vias <NUM>, <NUM>, <NUM> are the only vias that intra-couple the layer set <NUM>. In these examples, the two, directly axially adjacent PCB layers <NUM> and <NUM> are not directly electrically coupled to each other. In <FIG> each of the vias <NUM> couples a pair of non-adjacent PCB layers <NUM> while bypassing (i.e., making no contact to) the intervening PCB layer <NUM>. For example, via <NUM> couples PCB layer <NUM> to PCB layer <NUM>, and makes no contact with PCB layer <NUM>. Conversely, each of the vias <NUM> couples a pair of adjacent PCB layers <NUM>. For example, via <NUM> couples PCB layer <NUM> to PCB layer <NUM>. Each via <NUM>, <NUM> that couples together a respective pair of PCB layers, forms a corresponding layer pair <NUM>. For example, layer pair <NUM> includes PCB layer <NUM> and PCB layer <NUM>. Layer pair <NUM> includes PCB layer <NUM> and PCB layer <NUM>. Layer pair <NUM> includes PCB layer <NUM> and PCB layer <NUM>. Layer pair <NUM> includes PCB layer <NUM> and PCB layer <NUM>. Layer pair <NUM> includes PCB layer <NUM> and PCB layer <NUM>. Layer pair <NUM> includes PCB layer <NUM> and PCB layer <NUM>. Layer pair <NUM> includes PCB layer <NUM> and PCB layer <NUM>.

In <FIG>, each via is shown having a blunt end and a pointed end. This shape is not intended to imply any structural difference between the two ends of each via, but rather is intended to provide a consistent indication of the direction of current flow through each via. Moreover, while each via is also shown as extending vertically only as far as necessary to couple the corresponding pair of PCB layers <NUM>, in certain embodiments each via can be implemented as a plated through-hole via extending through the entire PCB (e.g., see vias <NUM> in <FIG>). Each of such plated through-hole vias can make contact with any PCB layer <NUM> having a trace <NUM> that overlaps such a via. In the embodiment shown in <FIG>, a given through-hole via overlaps and makes a connection with only two PCB layers <NUM>, while the traces <NUM> of all remaining PCB layers <NUM> do not overlap the given via and are not connected to the given via. Alternatively, some embodiments can include buried vias that vertically extend only between the corresponding PCB layers <NUM> to be connected.

<FIG>, <FIG> disclose embodiments of a module <NUM> for one or more axial field rotary energy devices <NUM>. Device(s) <NUM> can comprise any of the axial field rotary energy device embodiments disclosed herein. In the embodiments shown in these figures, the module <NUM> includes a housing <NUM> having a side wall <NUM>, three stators (shown as PCB stator panel <NUM>), and four rotor assemblies <NUM>, <NUM>. Each rotor assembly <NUM> is vertically disposed between two stators <NUM>, and includes a pair of identical rotor panels <NUM> and a group of rotor permanent magnets <NUM>. Each rotor panel <NUM> includes a set of recessed indentations to position each of the rotor magnets <NUM>, and the two rotor panels <NUM> are secured together to sandwich each of the group of rotor magnets between the opposing upper and lower rotor panels <NUM>. Each rotor assembly <NUM> is vertically disposed between a stator <NUM> and a housing <NUM>, and includes a torque plate <NUM>, a rotor panel <NUM>, and a group of rotor permanent magnets <NUM>.

The vertical spacing between rotor assemblies (e.g., <NUM>, <NUM>) is maintained by spacers (e.g., <NUM>, <NUM>) that extend from one rotor assembly to the adjacent rotor assembly through a hole in the intervening stator panel <NUM>. The rotor spacing corresponds to the thickness of the stator panel <NUM> and the desired air gap spacing (such as above and/or below) the stator panel <NUM>. Each rotor spacer can define the air gap between the rotor assembly and the stator (and also can define the height <NUM> of the side wall slots, as noted below). Each rotor spacer is positioned between two rotor assemblies. For example, rotor spacer <NUM> is positioned between the uppermost rotor assembly <NUM> and the adjacent inner rotor assembly <NUM> (and likewise for the lowermost rotor assembly <NUM>). Each rotor spacer <NUM> is positioned between adjacent inner rotor assemblies <NUM>. As is depicted here, such rotor spacer <NUM> can have a different thickness as rotor spacer <NUM>, due to mechanical differences in the uppermost and lowermost rotor assemblies <NUM> relative to the inner rotor assemblies <NUM>, to define the same air gap spacing between all rotors and stators. The use of the rotor spacers <NUM>, <NUM> enables stacking multiple rotors (e.g., rotor assemblies <NUM>, <NUM>), which can provide significant flexibility in the configuration of module <NUM>.

Embodiments of the housing <NUM> can include a side wall <NUM> (<FIG> and <NUM>). Side wall <NUM> can be configured to orient the stator (e.g., stator panel <NUM>) at a desired angular orientation with respect to the axis <NUM>. For applications including a plurality of stators <NUM>, the side wall <NUM> can comprise a plurality of side wall segments <NUM>. The side wall segments <NUM> can be configured to angularly offset the plurality of stators <NUM> at desired electric phase angles (see, e.g., <FIG> and <FIG>) for the module <NUM>, relative to the axis. In one example, the side wall <NUM> can include a radial inner surface having one or more slots <NUM> formed therein. Each slot <NUM> can be configured to receive and hold the outer edge of the stator <NUM> to maintain the desired angular orientation of the stator <NUM> with respect to the axis <NUM>. In the embodiment shown in <FIG>, each side wall <NUM> includes three slots <NUM> formed between mating pairs of side wall segments <NUM>. In some embodiments the upper and lower sidewall segments <NUM> of such mating pair are identical and thus can be used interchangeably, but in other contemplated embodiments the upper and lower side wall segments <NUM> can be different due to asymmetrical slots <NUM>, differences in mounting hole placement, or some other aspect.

In addition to providing the angular offset of the stators <NUM> as described above, the slots <NUM> can be configured to axially, such as vertically, position the outer edge of each stator <NUM> at prescribed axial positions with respect to other stators <NUM>. Since the rotor spacers <NUM>, <NUM> determine the axial spacing between each stator <NUM> (at the innermost extent thereof) and the corresponding rotor assembly (e.g., <NUM>, <NUM> in <FIG>, <FIG>, and <FIG>) on either axial side (e.g., above and below) each stator <NUM>, the combination of the side wall slots <NUM> (i.e., the height <NUM> of such slots <NUM>) and the rotor spacers <NUM>, <NUM> serve to maintain a precise air gap spacing between stators <NUM> and rotor assemblies <NUM>, <NUM>. In other embodiments having a single stator <NUM>, each side wall segment <NUM> can be configured to provide one side wall slot <NUM>. The group of side wall segments <NUM> together provide numerous slots <NUM> (e.g., eight such slots <NUM>) radially spaced around the module <NUM>. Collectively such side wall slots <NUM> can be viewed as facilitating the air gap spacing between the stator and the adjacent rotor.

Versions of the module <NUM> can include a housing <NUM> having mechanical features (e.g., keyed shafts <NUM> in <FIG>) configured to mechanically couple the housing <NUM> to a second housing <NUM> of a second module <NUM>. In addition, housing <NUM> can be configured with electrical elements (e.g., electrical connector couplings <NUM> in <FIG>) to electrically couple the housing <NUM> to the second housing <NUM>. In one example, the module <NUM> is air cooled and is not liquid cooled. In other versions, liquid- cooled embodiments can be employed.

In some examples, the module <NUM> can be configured to be indirectly coupled to the second module <NUM> with an intervening structure, such as a frame <NUM> (<FIG>). The module <NUM> can be configured to be directly coupled to the frame <NUM>, such that the module <NUM> is configured to be indirectly coupled to the second module <NUM> with other components depending on the application. In another example, the module <NUM> can be configured to be directly coupled to the second module <NUM> without a frame, chassis or other intervening structure.

In some embodiments, at least one rotor <NUM>, at least one magnet <NUM> and at least one stator <NUM> having at least one PCB <NUM> with at least one PCB layer <NUM> having at least one trace <NUM>, can be located inside and surrounded by the housing <NUM>.

In some versions, each module <NUM> consists of a single electrical phase. In other versions each module <NUM> comprises a plurality of electrical phases. Examples of each module <NUM> can include a plurality of PCB panels <NUM> (<FIG>). Each PCB panel <NUM> can comprise a single electrical phase or a plurality of electrical phases. The PCB panels can be unitary panels or can comprise stator segments as described elsewhere herein.

In one version, the module <NUM> and the second module <NUM> can be configured to be identical to each other. In another version, the module <NUM> and the second module <NUM> can differ. For example, the module <NUM> can differ from the second module <NUM> by at least one of the following variables: power input or output, number of rotors <NUM>, number of magnets <NUM>, number of stators <NUM> (see previous drawings), number of PCBs <NUM>, number of PCB layers <NUM> (see previous drawings), number of traces <NUM> (see previous drawings), and angular orientation with respect to the axis <NUM>. For example, in some embodiments one or more of these variables can be modified to achieve differences in power efficiency, torque, achievable revolutions per minute (RPM), so that different modules <NUM> can be utilized to better tailor operation as a function of the load or other desired operating parameter.

Some embodiments of the module <NUM> can include at least one latch <NUM> (<FIG>) configured to mechanically secure the modules together. <FIG> depicts modules nested together with the latches <NUM> open, and <FIG> depicts modules nested together with the latches <NUM> closed. In one example, the latches <NUM> can be symmetrically arrayed with respect to the axis <NUM>. In another version, a top module (not shown) can be configured to be axially on top of another module, and the top module can differ structurally from the second module. For example, the top module <NUM> can include latches <NUM> only on its bottom side, and omit such latches <NUM> on its top side. As another example, the shaft <NUM> can extend from the bottom module <NUM>, but not from the top module <NUM>.

As shown in <FIG>, the module <NUM> can include a keyed shaft <NUM>. Module <NUM> can be mounted to the keyed shaft which can be configured to mechanically couple to another module <NUM>.

Some embodiments can further comprise a body <NUM> (<FIG>) (also referred to herein as an "enclosure"). Body <NUM> can be configured to contain and coaxially mount a plurality of the modules <NUM> within the body <NUM>. In the example illustrated, the body <NUM> comprises two halves that are coupled together with fasteners. For versions where each module <NUM> comprises a single electrical phase, and the body <NUM> can be configured to maintain the modules <NUM> at a desired electrical phase angle with respect to the axis <NUM>. For versions where the body <NUM> comprises a plurality of electrical phases, and the body <NUM> can be configured to maintain the modules <NUM> at desired electrical phase angles with respect to the axis <NUM>.

In other versions, there can be a plurality of bodies <NUM>. Each body <NUM> can include mechanical features such as coupling structures configured to mechanically couple each body <NUM> to at least one other body <NUM>, and electrical elements configured to electrically couple each body <NUM> to at least one other body <NUM>. Each body <NUM> can be configured to directly or indirectly couple to at least one other body <NUM>.

In some generator embodiments, a body (or more than one intercoupled bodies) can include a number of electrical phases (such as about <NUM> to <NUM>; e.g., at least <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> or more) electrical phases of alternating current output. Thus, the AC current output can act like a DC-like output ripple without being rectified or requiring a power conversion. In other versions, such AC current output can be rectified.

Embodiments of a system for providing energy also are disclosed. For example, the system can include a plurality of modules <NUM> comprising axial field rotary energy devices. The modules <NUM> can be interchangeably connectable to each other to configure the system for a desired power output. Each module can be configured based on any of the embodiments described herein. The system can comprise a generator or a motor. Embodiments of the system can include at least two of the modules <NUM> configured to differ. For example, the modules <NUM> can differ from each other by at least one of the following variables: power output or input, number of rotors, number of magnets, number of stators, number of PCBs, number of PCB layers, number of coils, and angular orientation with respect to the axis.

Embodiments of a method of repairing an axial field rotary energy device are disclosed as well. For example, the method can include the following steps: providing a body <NUM> having a plurality of modules <NUM>. Each module <NUM> can be configured as described for any of the embodiments disclosed herein. The method also can include mechanically and electrically coupling the modules <NUM> such that the modules <NUM> are coaxial; operating the axial field energy device; detecting a problem with one of the modules <NUM> and stopping operation of the axial field energy device; opening the body <NUM> and de- attaching the problem module <NUM> from all other modules <NUM> to which the problem module <NUM> is attached; installing a replacement module <NUM> in the body <NUM> in place of the problem module <NUM> and attaching the replacement module <NUM> to the other modules <NUM> to which the problem module <NUM> was attached; and then re-operating the axial field energy device.

Other embodiments of the method include angularly aligning the modules to at least one desired electrical phase angle with respect to the axis. In another version, the method can include providing a plurality of bodies <NUM>, and mechanically and electrically coupling the bodies <NUM>.

Still other embodiments of a method of operating an axial field rotary energy device can include providing an enclosure having a plurality of modules, each module comprises a housing, rotors rotatably mounted to the housing, each rotor comprises an axis and a magnet, stators mounted to the housing coaxially with the rotors, each stator comprises a printed circuit board (PCB) having a coil, each stator consists of a single electrical phase, and selected ones of the stators are set at desired phase angles with respect to the axis; mechanically and electrically coupling the modules such that the modules are coaxial within the enclosure; and then operating the axial field energy device. In other words, setting the single phase stators at the same phase angle can form a single phase machine, and setting the single phase stators at varying phase angles can form a multi-phase machine (or more than <NUM> phases).

Optionally, the enclosure and each module can comprise a single electrical phase, and the method can comprise angularly aligning the modules at a desired electrical phase angle with respect to the axis. The method can include the enclosure with a plurality of electrical phases, each module comprises a single electrical phase, and angularly orienting the modules at desired electrical phase angles with respect to the axis. The enclosure and each module can include a plurality of electrical phases, and angularly misaligning the modules at desired electrical phase angles with respect to the axis.

Some versions of the method can include providing a plurality of bodies, and the method further comprises mechanically and electrically coupling the bodies to form an integrated system. Each module can include a plurality of stators that are angularly offset from each other with respect to the axis at desired electrical phase angles. In one example, each stator consists of only one PCB. In other examples, each stator comprises two or more PCBs that are coupled together to form each stator. In still another version, the enclosure can have a number electrical phases of alternating current (AC) output that is substantially equivalent to a clean direct current (DC)-like ripple without a power conversion, as described herein.

In other versions, a method of repairing an axial field rotary energy device can include providing a plurality of bodies that are coupled together, each enclosure having a plurality of modules, each module comprising a housing, a rotor rotatably mounted to the housing, the rotor comprises an axis and a magnet, a stator mounted to the housing coaxially with the rotor, and the stator comprises a printed circuit board (PCB); mechanically and electrically coupling the modules; operating the axial field rotary energy device; detecting an issue with a first module in a first enclosure and stopping operation of the axial field rotary energy device; opening the first enclosure and disassembling the first module from the first enclosure and any other module to which the first module is attached; installing a second module in the first enclosure in place of the first module and attaching the second module to said any other module to which the first module was attached; and then re-operating the axial field rotary energy device.

Embodiments of each module can have only one orientation within the enclosure, such that each module can be installed or uninstalled relative to the enclosure in singular manners. The purpose of such designs is so the person doing work on the system cannot reinstall new modules into an existing system the wrong position. It can only be done in only one orientation. The method can occur while operation of the AFRED is suspended, and treatment of the first module occurs without interrupting said any other module, and without modifying or impacting said any other module.

<FIG> depicts another embodiment of a PCB stator <NUM> for an axial field rotary energy device, such as those disclosed herein. PCB stator <NUM> comprises a substrate having one or more traces <NUM> that are electrically conductive. In the version shown, PCB stator <NUM> comprises eight coils of traces <NUM>. In addition, PCB stator <NUM> can comprise more than one layer of traces <NUM>. The traces <NUM> on each layer are co-planar with the layer. In addition, the traces <NUM> are arrayed about a central axis <NUM> of the PCB stator.

<FIG> is an enlarged top view of a portion of the PCB stator of <FIG>. In the embodiment shown, each trace <NUM> comprises radial portions <NUM> (relative to axis <NUM>) and end turns <NUM> extending between the radial portions <NUM>. Each trace <NUM> can be split with a slit <NUM>. In some versions, only radial portions <NUM> comprise slits <NUM>. Slits <NUM> can help reduce eddy current losses during operation. Eddy currents oppose the magnetic field during operation. Reducing eddy currents increases magnetic strength and increases efficiency of the system. In contrast, wide traces can allow eddy currents to build. The slits in the traces <NUM> can reduce the opportunity for eddy currents to form. The slits can force the current to flow through the traces <NUM> more effectively.

The axial field rotary energy device can comprise a "smart machine" that includes one or more sensors integrated therewith. In some embodiments, such a sensor can be configured to monitor, detect, or generate data regarding operation of the axial field rotary energy device. In certain embodiments, the operational data can include at least one of power, temperature, rate of rotation, rotor position, or vibration data.

Versions of the axial field rotary energy device can comprise an integrated machine that includes one or more control circuits integrated therewith. Other versions of the axial field rotary energy device can comprise a fully integrated machine that includes one or more sensors and one or more control circuits integrated therewith. For example, one or more sensors and/or control circuits can be integrated with the PCB and/or integrated with the housing. For motor embodiments, these control circuits can be used to drive or propel the machine. For example, in some motor embodiments, such a control circuit can include an input coupled to receive an external power source, and can also include an output coupled to provide a current flowing through one or more stator coils. In some embodiments the control circuit is configured to supply torque and/or torque commands to the machine. In some generator embodiments, such a control circuit can include an input coupled to receive the current flowing through the coil, and can also include an output coupled to generate an external power source.

For example, one or more sensors and/or control circuits can be integrated with the PCB stator <NUM>. <FIG> shows another exemplary stator <NUM> having integrated sensors (e.g., <NUM>, <NUM>) that are attached to its uppermost PCB layer <NUM>. One such sensor <NUM> is coupled to a secondary coil <NUM> that can be used to transmit/receive data to/from an external device, and can be also used to couple power to the sensor <NUM>. In some embodiments the secondary coil can be configured to utilize magnetic flux developed during operation to provide power for the sensor <NUM>. In some embodiments the secondary coil can be configured to receive inductively coupled power from an external coil (not shown). The secondary coil <NUM> may also be referred to herein as a micro-coil, or a miniature coil, as in certain embodiments such a secondary coil can be much smaller than a stator coil <NUM>, but no relative size inference is intended. Rather, such a secondary coil <NUM> is distinct from the stator coils <NUM> that cooperate with the rotor magnets, as described above. Such a secondary coil integrated with the PCB stator <NUM> can, in certain embodiments, be disposed on the PCB stator <NUM> (e.g., fabricated on, or attached to, its uppermost PCB layer <NUM>). Such a secondary coil integrated with the PCB stator <NUM> can, in certain embodiments, be disposed within (i.e., embedded within) the PCB stator <NUM>. In some embodiments, the secondary coil <NUM> provides power to a sensor connected thereto. Such coupled power can be primary or auxiliary power for the sensor.

Sensor <NUM> is coupled to the first terminal <NUM> for one of the traces <NUM> on the upper PCB layer <NUM>, and can sense an operating parameter such as voltage, temperature at that location, and can also be powered by the attached coil (e.g., one of the coils <NUM>). Sensor <NUM> is coupled to an external terminal <NUM>, and likewise can sense an operating parameter such as voltage, temperature at that location, and can also be powered by the voltage coupled to the external terminal <NUM>. Sensor <NUM> is disposed at an outer edge of the PCB stator <NUM>, but is coupled to no conductor on the PCB layer <NUM>.

In some embodiments, such a sensor can be embedded directly in one of the coils <NUM> and can be electrically powered directly by the coil <NUM>. In some embodiments, such a sensor can be powered and connected to the coil <NUM> through a separate connection that is disposed on or within the PCB layer <NUM>, such as the connection between the first terminal <NUM> and sensor <NUM>. Such a connection can be disposed on the PCB layer <NUM> or disposed within the PCB (e.g., on an internal layer of the PCB). In other embodiments, the sensor and/or circuitry can get power from an external power source. For example, one type of external power source can be a conventional wall electrical socket which can be coupled to the housing of the motor or generator.

The sensors can provide operators of generator or motor products with real time operational data as well as, in certain embodiments, predictive data on various parameters of the product. This can include how the equipment is operating, and how and when to schedule maintenance. Such information can reduce product downtime and increase product life. In some embodiments, the sensor can be integrated within the housing. In some examples, the sensors can be embedded within the PCB stator <NUM>, as is shown in <FIG> (e.g., sensors <NUM>, <NUM>, <NUM>, <NUM>, and coil <NUM>).

One example of a sensor for these applications is a Hall effect sensor. Hall effect sensors are used for proximity switching, positioning, speed detection, and current sensing applications. In its simplest form, the Hall effect sensor operates as an analog transducer, directly returning a voltage.

Another example of a sensor is an optical sensor. Optical sensors can measure the intensity of electromagnetic waves in a wavelength range between UV light and near infrared light. The basic measurement device is a photodiode. Combining a photodiode with electronics makes a pixel. In one example, the optical sensor can include an optical encoder that uses optics to measure or detect the positions of the magnetic rotor.

Another example of a sensor is a thermocouple sensor to measure temperature. Thermocouples comprise two wire legs made from different metals. The wires legs are welded together at one end, creating a junction. The junction is where the temperature is measured. When the junction experiences a change in temperature, a voltage is created.

Another optional sensor is an accelerometer. Accelerometers are an electromechanical device used to measure acceleration forces. Such forces can be static, like the continuous force of gravity or, as is the case with many mobile devices, dynamic to sense movement or vibrations. Acceleration is the measurement of the change in velocity, or speed divided by time.

A gyro sensor, which functions like a gyroscope, also can be employed in these systems. Gyro sensors can be used to provide stability or maintain a reference direction in navigation systems, automatic pilots, and stabilizers.

The PCB stator <NUM> also can include a torque sensor. A torque sensor, torque transducer or torque meter is a device for measuring and recording the torque on a rotating system, such as the axial field rotary energy device.

Another optional sensor is a vibration sensor. Vibration sensors can measure, display and analyze linear velocity, displacement and proximity, or acceleration. Vibration, even minor vibration, can be a telltale sign of the condition of a machine.

In various embodiments, the sensors depicted in <FIG> can also represent control circuits integrated with the PCB stator <NUM>. Such control circuits can be disposed on a surface of the PCB (analogously to the sensors depicted in <FIG>), disposed within (i.e., embedded within) the PCB (analogously to the sensors depicted in <FIG>), and/or integrated with or within the housing (e.g., housing <NUM> in <FIG>).

In some generator embodiments, the control circuit can implement power conversion from an AC voltage developed in the stator coils to an external desired power source (e.g., an AC voltage having a different magnitude than the coils voltage, a DC voltage developed by rectifying the coils voltage). In some motor embodiments, the control circuit can implement an integrated drive circuitry that can provide desired AC current waveforms to the stator coils to drive the motor. In some examples, the integrated drive can be a variable frequency drive (VFD), and can be integrated with the same housing as the motor. The sensors and/or circuitry disclosed herein can be wirelessly or hard-wired to any element of, on or in the housing. Alternatively, the sensors and/or circuitry can be located remotely relative to the housing.

Each of these sensors and control circuits can include a wireless communication circuit configured to communicate with an external device through a wireless network environment. Such wireless communication can be unidirectional or bidirectional, and can be useful for monitoring a status of the system, operating the system, communicating predictive data, etc. The wireless communication via the network can be conducted using, for example, at least one of long term evolution (LTE), LTE-advanced (LTE-A), code division multiple access (CDMA), wideband CDMA (WCDMA), universal mobile telecommunication system (UMTS), wireless broadband (WiBro), or global system for mobile communications (GSM), as a cellular communication protocol.

Additionally or alternatively, the wireless communication can include, for example, short-range communication. The short-range communication can be conducted by, for example, at least one of wireless fidelity (WiFi), Bluetooth®, near field communication (NFC), or GNSS. GNSS can include, for example, at least one of global positioning system (GPS), Glonass® global navigation satellite system, Beidou® navigation satellite system, or Galileo®, the European global satellite-based navigation system. In the present disclosure, the terms 'GPS' and 'GNSS' are interchangeably used with each other. The network can be a communication network, for example, at least one of a computer network (for example, local area network (LAN) or wide area network (WAN)), the Internet, or a telephone network.

In certain embodiments, such a wireless communication circuit can be coupled to a secondary coil (e.g., secondary coil <NUM>) to communicate telemetry information, such as the operational data described above.

<FIG> show an embodiment of an assembly for mechanically coupling together stator segments <NUM> to form a stator. A clasp <NUM> slides over portions of a mounting pad <NUM> on two adjacent stator segments <NUM>, which is secured by a pair of nuts on each of two bolts (e.g., bolt <NUM>). The clasp <NUM> includes an alignment tab <NUM> that can be positioned into a side wall slot <NUM> as described above. The inner diameter edge of the two adjacent stator segments <NUM> slides into a channeled rotor spacer <NUM> in the shape of an annular ring. In some embodiments this rotor spacer <NUM> can ride on a thrust bearing with the rotor to allow the rotor spacer <NUM> and stator to remain stationary while the rotor rotates. In other embodiments a rotor spacer as described above (e.g., <FIG>, <FIG>) can fit within the open center of the channeled rotor spacer <NUM>.

Electrical connection between adjacent stator segments <NUM>, <NUM> can be implemented using a wire <NUM> between respective circuits <NUM>, <NUM>. Circuit <NUM> can connect to a trace on the upper layer (or another layer using a via) of the stator segment <NUM>. Similarly, circuit <NUM> can connect to a trace on any layer of the stator segment <NUM>. Such circuits <NUM>, <NUM> can include any of the sensors described above (<FIG>), but can also merely provide an electrical connection from the respective PCB to the wire <NUM>. In other embodiments, electrical connection also can be made via the mounting surface of the PCB being a conductive material and connected to the coil and then coupling those components through the clasp, which also can include conductive material on the inner surface thereof.

Electrical connection can also be implemented using the clasp <NUM> combination with an electrically conductive mounting pad <NUM>. If the mounting pad <NUM> is continuous and unbroken, the clasps <NUM> can provide a common electrical connection around the circumference of the stator. If such mounting pads are discontinuous and broken into two pieces (as shown by the dash lines, with each piece coupled to a respective terminal of a trace on that segment, the clasps <NUM> can serially connect such stator segments.

The axial field rotary energy device is suitable for many applications. The PCB stator <NUM> can be configured for a desired power criteria and form factor for devices such as permanent magnet-type generators and motors. Such designs are lighter in weight, easier to produce, easier to maintain and more capable of higher efficiency.

Examples of permanent magnet generator (PMG) applications can include a wind turbine generator, micro-generator application, permanent magnet direct drive generator, steam turbine generator, hydro generator, thermal generator, gas generator, wood-fire generator, coal generator, high frequency generator (e.g., frequency over <NUM>), portable generator, auxiliary power unit, automobiles, alternator, regenerative braking device, PCB stator for regenerative braking device, back-up or standby power generation, PMG for back up or standby power generation, PMG for military usage and a PMG for aerospace usage.

In other embodiments, examples of a permanent magnet motor (PMM) can include an AC motor, DC motor, servo motor, stepper motor, drone motor, household appliance, fan motor, microwave oven, vacuum machine, automobile, drivetrain for electric vehicle, industrial machinery, production line motor, internet of things sensors (IOT) enabled, heating, ventilation and air conditioning (HVAC), HVAC fan motor, lab equipment, precision motors, military, motors for autonomous vehicles, aerospace and aircraft motors.

It can be advantageous to set forth definitions of certain words and phrases used throughout this patent document. The term "communicate," as well as derivatives thereof, encompasses both direct and indirect communication. The phrase "associated with," as well as derivatives thereof, can mean to include, be included within, interconnect with, contain, be contained within, connect to or with, couple to or with, be communicable with, cooperate with, interleave, juxtapose, be proximate to, be bound to or with, have, have a property of, have a relationship to or with, or the like. The phrase "at least one of," when used with a list of items, means that different combinations of one or more of the listed items can be used, and only one item in the list can be needed. For example, "at least one of: A, B, and C" includes any of the following combinations: A, B, C, A and B, A and C, B and C, and A and Band C.

Also, the use of "a" or "an" are employed to describe elements and components described herein. This description should be read to include one or at least one and the singular also includes the plural unless it is obvious that it is meant otherwise.

A printed circuit board (PCB) is also known as a printed wiring board (PWB), since such a board, as manufactured, usually contains wiring on one or more layers, but no actual circuit elements. Such circuit elements are subsequently attached to such a board. As used herein, no distinction between PCB and PWB is intended. As used herein, a coil on a PCB is an electrically conductive coil. As used herein, a component or object "integrated with" a structure can be disposed on or within the structure. Such a component or object can be mounted, attached to, or added to the structure after the structure itself is manufactured, or the component or object can be embedded within or fabricated with the structure.

Claim 1:
An axial field rotary energy device (<NUM>), comprising:
a housing (<NUM>);
a plurality of rotors (<NUM>) rotatably mounted to the housing, wherein the rotors comprise an axis (<NUM>) and a plurality of magnets (<NUM>); and
a stator (<NUM>) mounted to the housing coaxially with the rotors,
the stator comprises a printed circuit board "PCB" (<NUM>) having a plurality of PCB layers (<NUM>),
each PCB layer comprising a respective plurality of coils (<NUM>) that are co-planar and angularly and symmetrically spaced apart from each other relative to the axis,
each coil is continuous and concentric in a single plane from an outermost coil portion to a concentric innermost coil portion, and
the coils in adjacent PCB layers are circumferentially aligned with each other relative to the axis to define symmetric stacks of coils in an axial direction,
each coil includes a first terminal (<NUM>) at the outer edge of the coil, and a second terminal (<NUM>) in the center of the coil,
wherein each coil is not directly connected to an adjacent coil on the same PCB layer, but is directly connected to a corresponding coil on another PCB layer through a via (<NUM>) to create a coil pair (<NUM>);
each coil pair (<NUM>) is electrically coupled to another coil pair through another via (<NUM>).