Patent Grant
12368284
The present invention relates generally to high-speed, high-voltage switching systems and devices. More particularly, the invention is a rotary spark gap having a plurality of rotors. In an exemplary embodiment, the rotary spark gap system has two or more rotors each having a plurality of rotor points that are spaced apart in an axial direction and displaced in a circumferential direction relative to one another.
Rotary spark gaps are known for use in high-speed, high-voltage switching systems and devices. By way of an example, a transmitter having a capacitor charged with alternating current (AC) from a high-voltage transformer may be equipped with a rotary spark gap for discharging the capacitor. The rotary spark gap may consist of a number of electrodes spaced circumferentially around a wheel that is spun (rotated) by an electric motor. The electrodes on the wheel produce sparks as they are rotated past a stationary electrode.
A Tesla coil is a particular high-speed, high-voltage device that utilizes a spark gap. The spark gap device functions as the high-speed switch that turns the high-voltage of the primary coil on and off rapidly, for example up to five thousand (5000) times per second, to produce the resonance in the secondary coil (i.e., output coil). The plasma produced by the arcing which occurs between the rotor and the electrode generates a considerable amount of heat that rapidly erodes the face of the electrode. Erosion of the electrode face is the foremost cause of failure for a Tesla coil having any significant power. Consequently, Tesla coils equipped with conventional spark gaps have a very short operating cycle and limited life span. Generally, it is only about five (5) to fifteen (15) minutes of operating before spark gap failure occurs due to overheating. The short time before spark gap failure limits the length of the operating cycle, requires frequent maintenance, and results in a shorted life span of the Tesla coil.
Certain applications using a Tesla coil require substantially longer operating cycles. A particular such application is a resonator system for a Pulsed Electromagnetic Field (PEMF) therapy device that utilizes a Tesla coil to produce resonance. Effective PEMF therapy devices need to be able to operate for extended periods, up to several hours non-stop, without overheating and/or experiencing spark gap failure that requires frequent maintenance or results in a shortened life span.
In view of the foregoing, it is apparent a need exists for an improved high-speed, high-voltage switching system or device. A more particular need exists for an improved spark gap system or device that operates as a high-speed, high-voltage switch, for example, in a Tesla coil. A further particular need exists for a spark gap system or device that overcomes the problems and deficiencies associated with conventional spark gaps. A further particular need exists for a rotary spark gap that has a longer operating cycle without overheating and/or experiencing spark gap failure that requires frequent maintenance or results in a shortened life span. A further need exists for an improved spark gap having a reduced operating temperature that increases the operating cycle time, durability and life span of the spark gap.
In one aspect, the present invention is embodied by an improved rotary spark gap that operates as a high-speed, high-voltage switch. The rotary spark gap includes a rotor assembly having at least one rotor with a plurality of rotor points disposed on the rotor, and at least one rotatable rotor shaft configured and operable for rotating the rotor. The rotor assembly further includes at least one electrode disposed within the housing and operable for electrically coupling with the rotor points on the rotor. The rotor assembly further includes at least one heat sink in heat-conducting relation with the at least one electrode configured and operable for conducting heat away from the rotor assembly.
In an embodiment of the rotary spark gap, the rotor assembly includes a plurality of rotors each having a plurality of rotor points disposed on the rotor. In a particular example of the embodiment, each rotor is a generally annular rotor disk and the plurality of rotor points are disposed on the periphery of the rotor disk and spaced apart around the outer circumference of the rotor disk. The plurality of rotors is spaced apart in an axial direction by insulating spacers made of an insulating material.
In another embodiment of the rotary spark gap, the rotor assembly includes a plurality of electrodes disposed on opposite sides of the rotors. In a particular example of the embodiment, the electrodes are bar electrodes that span the rotors and the insulating spacers in the axial direction.
In another embodiment of the rotary spark gap, each rotor is made of an electrically-conductive material and each electrode is made of an electrically-conductive material. In a particular example of the embodiment, each rotor is made of a copper (Cu) metal material and each electrode is made of a copper (Cu) metal material.
In another embodiment of the rotary spark gap, the rotor shaft is rotated by a belt drive and extends in the axial direction through each rotor and each insulating spacer. In a particular example of the embodiment, the rotor shaft is mounted on high-speed bearings and the belt drive is operatively connected to a rotor shaft drive motor. The rotor shaft drive motor may be an electric motor and may be disposed adjacent to the exterior of the rotary spark gap.
In another embodiment of the rotary spark gap, each heat sink is made of an aluminum (Al) metal material.
In another embodiment of the rotary spark gap, each electrode is slotted to permit adjustment of the position of the electrode as the electrode wears.
In another aspect, the present invention is embodied by a rotary spark gap for a Tesla coil. The rotary spark gap includes a housing defining an interior compartment configured to contain a rotor assembly. The rotor assembly includes a plurality of electrically-conductive annular rotor disks each having a plurality of rotor points disposed on the periphery of the rotor disk and spaced apart around the outer circumference of the rotor disk in a radial direction. The rotor disks are mounted on a rotatable rotor shaft in an axial direction and spaced apart by insulating spacers. The rotor assembly further includes a plurality of electrically-conductive bar electrodes disposed within the housing on opposite sides of the rotor disks and spacers and operable for electrically coupling with the rotor points. In a particular example of the embodiment, the rotor assembly includes four (4) rotor disks each having a total of nine (9) rotor points equally spaced, i.e., forty degrees (40°), around the outer circumference of the rotor disk, and two (2) bar electrodes. The rotor assembly further includes a heat sink made of a thermally-conductive material in heat-conducting relation with each bar electrode. The rotor assembly further includes a rotor shaft drive motor operable for rotating the rotor shaft with the rotor disks and insulating spacers mounted on the rotor shaft.
In another embodiment, each rotor disk is made of a copper (Cu) metal material and each bar electrode is made of a copper (Cu) metal material.
In another embodiment, each heat sink is made of an aluminum (Al) metal material.
In another embodiment, each bar electrode is slotted to permit adjustment of the position of the electrode as the electrode wears due to plasma arcing.
In another embodiment, the rotor shaft is a belt-driven rotor shaft that is mounted on high-speed bearings and operatively connected to a rotor shaft drive motor.
In another embodiment, the housing is made of an insulating material and includes a cover for enclosing the rotor assembly within the housing. In a particular example of the embodiment, the housing is an insulated, generally hollow, box-like container that defines the interior compartment configured to contain the rotor assembly.
Additional aspects, objects, features and advantages of the present invention will be made apparent or will be readily understood and appreciated by those skilled in the relevant art, as exemplary embodiments of the invention shown in the accompanying drawing figures are described in greater detail hereinafter. It is intended that all such aspects, objects, features and advantages of the invention envisioned by this disclosure of embodiments be encompassed by the appended claims given their broadest reasonable interpretation consistent with this disclosure from the viewpoint of one of ordinary skill in the art. Consequently, the various terms used in this disclosure should be construed according to their ordinary and customary meaning as understood by one of ordinary skill in the art at the time of the invention. The aspects, objects, features and advantages of the invention, as well as others not expressly disclosed, may be accomplished by one or more of the embodiments described herein and shown in the accompanying drawing figures, as well as others that are not expressly described and shown herein. However, it should be appreciated that the various embodiments and drawing figures provided herein are merely illustrative of the invention and its various forms, and that many modifications, changes, revisions and substitutions may be made to any of the embodiments without departing from the general concepts of the invention.
The aforementioned aspects, objects, features and advantages of the present invention, as well as the embodiments of the invention provided herein, will be more fully understood and appreciated when considered in conjunction with the accompanying drawing figures, in which like reference characters designate the same or similar parts throughout the several views.
The following is a description of exemplary embodiments of a rotary spark gap configured for use with high-speed, high-voltage switching systems and devices. In a particular application, the invention is an improved rotary spark gap for a Tesla coil that operates as the switch that turns the high voltage of the primary coil on and off at high speed (e.g., 5000 times per second) to achieve resonance in the secondary coil (output coil). The improved rotary spark gap reduces the heat produced by the plasma generated from the arcing between the rotor and the electrode that erodes the face of the electrode and consequently limits the operating cycles and life span of the spark gap. In addition to reducing the operating temperature to increase operating cycle time and durability, the improved rotary spark gap reduces the maintenance required and the noise produced by the rotary spark gap. As a result, the improved rotary spark gap is particularly well-suited for use with a Tesla coil in a Pulsed Electromagnetic Field (PEMF) therapy system or device.
Exemplary embodiments of the present invention are described more fully hereinafter with reference to the accompanying drawing figures. These exemplary embodiments show and describe an improved rotary spark gap system and device with reduced operating temperature that increases operating cycle time and life span, while reducing required maintenance and noise produced by the rotary spark gap. A particular embodiment of the rotary spark gap is configured for use as the high-speed, high-voltage switch for the primary coil of a Tesla coil suited for use in PEMF therapy system or device. However, it is not intended for the invention to be limited in any manner by the exemplary embodiments shown and described herein. Instead, it is expected the present invention will be given the broadest reasonable interpretation and construction consistent with this disclosure. Furthermore, unless a specific interpretation, definition or construction is expressly provided, the exemplary embodiments illustrated herein, and the various terms used herein should be given their ordinary and customary meanings as would be understood by a person of ordinary skill in the art at the time of the invention.
In one aspect, the present invention is embodied by an improved rotary spark gap, indicated generally herein by reference character 20.
Referring now to
In an embodiment, The rotor assembly 50 includes the rotor shaft 34 with a plurality of rotors 52 and a plurality of insulating spacers 54 mounted on the rotor shaft 34. In the exemplary embodiment shown in
Two rotors 52 spaced apart in the axial direction X and separated by an outer spacer 55 are disposed on each side of the center spacer 56. The rotors 52 and the outer spacers 55 are each provided with a plurality of holes 52′, 55′, respectively, that correspond to the holes 57′ formed through the flange 57. A plurality of fasteners 60, such as conventional threaded machine screws and nuts, secure the rotors 52 and outer spacers 55 together on the flange 57 of the center spacer 56 with the rotors 52 spaced apart in the axial direction X and separated by the outer spacers 55 and the flange 57 of the center spacer 56. The center spacer 56 with the rotors 52 and the outer spacers 55 secured thereon is mounted on and securely affixed to rotor shaft 34 at a predetermined location in the axial direction X. As best shown in
In an embodiment, each rotor 52 has a plurality of rotor points 53 disposed on the periphery of the rotor 52 and spaced apart around the outer circumference of the rotor 52 in a radial direction R. In the exemplary embodiment shown herein, each rotor 52 has a total of nine (9) rotor points 53 that are spaced apart around the outer circumference of the rotor 52 by about forty degrees (40°) in the radial direction R. The four (4) rotors 52 are mounted on the rotor shaft 34 with the rotors 52 out of phase with one another by about ten degrees (10°). As a result, the four (4) rotors 52 having nine (9) rotor points 53 each stacked together with the insulating spacers 54 appear as a thirty-six (36) point wheel when viewed from an end in the axial direction X, as illustrated by
The thirty-six (36) rotor points 53 electrically couple with electrodes of the rotary spark gap 20, as will be described hereinafter. Dividing the number of breaks and makes per rotor by the four (4) rotors 52 reduces the build-up of heat produced by the plasma generated by the rotary spark gap 20 since the number of operating cycles per rotation of the rotor assembly 50 is reduced from thirty-six (36) down to nine (9). Consequently, the number of electrodes can be reduced from eight (8) on a single rotor 52 having nine (9) rotor points 53 to two (2) electrodes that span the four (4) rotors 52.
The rotary spark gap 20 of this embodiment includes two (2) electrodes 70 schematically illustrated by broken lines in
In another aspect, the present invention is embodied by an improved rotary spark gap, indicated generally herein by reference character 120, configured for use with a Tesla coil, indicated generally herein by reference character 100. The rotary spark gap 120 operates as the high-speed, high-voltage switch for the primary coil of the Tesla coil 100 to achieve resonance in the secondary coil (output coil). In the exemplary embodiment shown in
A standard Tesla coil is an electrical resonant transformer circuit for producing high-voltage, low-current, high-frequency alternating current electrical energy. Standard Tesla coils can be operated for only short periods of time, and consequently, for only a short number of operating cycles, before overheating due to the heat produced from the plasma generated by the arcing between the rotor of the spark gap and the electrode. In addition, the considerable amount of heat erodes the face of the electrode, which causes premature failure and results in a short life span of a standard Tesla coil without frequent maintenance, repair and/or replacement.
The Tesla coil 100 configured with the rotary spark gap 120 of the present invention overcomes the problems and deficiencies of standard Tesla coils by reducing the operating temperature of the rotary spark gap 120. The reduced operating temperature of the rotary spark gap 120 increases the operating cycle time, durability and life span of the Tesla coil 100 with less frequent required maintenance, repair and/or replacement of the rotor or the electrode, while reducing the noise produced during operation of the Tesla coil 100. In general, the reduced operating temperature and increased operating cycle time durability and life span of the Tesla coil 100 is achieved by the pair of fixed bar electrodes 170 that align periodically (i.e., electrically couple) with the plurality of flying electrodes (i.e., the rotor points 153) on rotors 152 rotated at a constant angular velocity and generate high-frequency radio waves suitable for PEMF therapy. The rotary spark gap 120 can generate the high-frequency radio waves at about 5000 Hz with a rotor shaft speed of only about eighty-four hundred (8400) revolutions per minute (RPM) rather than the ten thousand (10,000) revolutions per minute (RPM) of a standard Tesla coil.
As previously described with respect to rotary spark gap 20, the rotor shaft 134 may be belt-driven by means of a belt (not shown) on a rotor shaft pulley 138 affixed to the rotor shaft 134 driven by an electric motor (not shown). In addition, the rotor shaft 134 may be mounted on high-speed bearings 133 adjacent each end of the rotor shaft 134 that are disposed within insulating and/or dampening isolators 135. As previously described, the opposite ends of the rotor shaft 134 are provided with a heat sink 144, 146 made of a suitable heat-conducting material, such as aluminum (Al) metal material, and having a plurality of heat-radiating fins 148 formed thereon for conducting heat generated by the rotatable rotor shaft 134 to the ambient environment in a conventional manner.
A rotor assembly 150 consists of the rotor shaft 134 with the rotors 152 and the insulating spacers 154 mounted on the rotor shaft 134. As previously described, each rotor 152 has a plurality of rotor points 153 on the periphery and spaced apart around the outer circumference of the rotor 152 in a circumferential direction R. As shown herein, four (4) rotors 152 are spaced apart and separated by a pair of annular outer spacers 155 and a center spacer 157 on the rotor shaft 134 in an axial direction X. The center spacer 157 is affixed to the rotor shaft 134 with the rotors 152 and the insulating spacers 154 secured together by a plurality of fasteners 160. Each rotor 152 has nine (9) rotor points 153 on the periphery spaced apart in the circumferential direction by about forty degrees (40°) and the rotors 152 are oriented out of phase with one another by about ten degrees (10°) so that the rotors 152 present as a thirty-six (36) point wheel when viewed from an end. The rotor points 153 on the rotors 152 electrically couple with a pair of bar electrodes 170 that span the rotors 152 on opposite sides of the rotor assembly 150 within the interior compartment 142 of the housing 140. Each bar electrode 170 is in heat-conducting relation with a corresponding thermally-conductive heat sink 172 operable for dissipating heat from the plasma generated by arcing between the rotor points 153 on the rotors 152 and the bar electrode 170.
Regardless of the foregoing description of exemplary embodiments of the invention, the optimum configuration of the article of manufacture, apparatus, device or system, and the manner of use, operation and steps of the associated methods, as well as reasonable equivalents thereof, are deemed to be readily apparent and understood by those skilled in the art. Accordingly, equivalent relationships to those shown in the accompanying drawing figures and described in this written description are intended to be encompassed by the invention given the broadest reasonable interpretation and construction of the appended claims, the foregoing written description and the accompanying drawing figures being considered as merely illustrative of the general concepts and principles of the invention. Furthermore, as numerous modifications and changes will readily occur to those skilled in the art, the invention is not intended to be limited to the specific configuration, construction, materials, manner of use and operation of the embodiments shown and described herein. Instead, all reasonably predictable and suitable equivalents and obvious modifications to the invention should be construed as falling within the scope of the invention as defined by the appended claims given their broadest reasonable interpretation and construction to one of ordinary skill in the art at the time of the invention in light of the foregoing written description and accompanying drawing figures.
| Number | Name | Date | Kind |
|---|---|---|---|
| 775872 | Strong | May 1904 | A |
| Number | Date | Country | |
|---|---|---|---|
| 20250219359 A1 | Jul 2025 | US |
