Patent Publication Number: US-9893555-B1

Title: Wireless charging of tools using a toolbox transmitter

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS 
     This application is a non-provisional patent application claiming the benefit of U.S. Provisional Patent Application Ser. No. 61/978,031, filed Apr. 10, 2014, entitled “METHODS AND SYSTEMS FOR MAXIMUM POWER POINT TRANSFER IN RECEIVERS”, which is incorporated by reference herein in its entirety for all purposes. This application is a continuation-in-part of U.S. Non-Provisional patent application Ser. No. 14/051,128, filed on Oct. 10, 2013, entitled “WIRELESS CHARGING OF TOOLS USING A TOOLBOX TRANSMITTER”, which is herein fully incorporated by reference in its entirety for all purposes. 
     This application relates to U.S. Non-Provisional patent application Ser. No. 13/891,430 filed May 10, 2013, entitled “Methodology For Pocket-forming,” U.S. Non-Provisional patent application Ser. No. 13/925,469 filed Jun. 24, 2013, entitled “Methodology for Multiple Pocket-Forming,” U.S. Non-Provisional patent application Ser. No. 13/946,082 filed Jul. 19, 2013, entitled “Method for 3 Dimensional Pocket-forming,” U.S. Non-Provisional patent application Ser. No. 13/891,399 filed May 10, 2013, entitled “Receivers for Wireless Power Transmission,” U.S. Non-Provisional patent application Ser. No. 13/891,445 filed May 10, 2013, entitled “Transmitters for Wireless Power Transmission;” U.S. Non-Provisional patent application Ser. No. 14/583,625, filed Dec. 27, 2014, entitled “Receivers for Wireless Power Transmission,” U.S. Non-Provisional patent application Ser. No. 14/583,630, filed Dec. 27, 2014, entitled “Methodology for Pocket-Forming,” U.S. Non-Provisional patent application Ser. No. 14/583,634, filed. Dec. 27, 2014, entitled “Transmitters for Wireless Power Transmission,” U.S. Non-Provisional patent application Ser. No. 14/583,640, filed Dec. 27, 2014, entitled “Methodology for Multiple Pocket-Forming,” U.S. Non-Provisional patent application Ser. No. 14/583,641, filed Dec. 27, 2014, entitled “Wireless Power Transmission with Selective Range,” U.S. Non-Provisional patent application Ser. No. 14/583,643, filed Dec. 27, 2014, entitled “Method for 3 Dimensional Pocket-Forming,” all of which are incorporated herein by reference in their entirety. 
    
    
     FIELD OF INVENTION 
     The present disclosure relates in general to wireless power transmission, and more specifically to configurations and methods of wireless power transmission using a toolbox and one or more cordless power tools. 
     BACKGROUND 
     Power tools such as drills, screwdrivers, circular saws, nailers, grinders, and the like, are proven to be very useful for domestic and industrial applications alike. These power tools are usually offered in corded and cordless versions. In particular, cordless power tools may be battery powered, which allows them to be portable and easy to store. In addition, cordless power tools may be particularly beneficial when working in unfinished construction sites where there may be no electrical power source available. However, unlike corded, cordless power tools may exhibit limited operating time and may rely on a suitable charged battery to operate efficiently. 
     What are needed are a device or system and a suitable method that may allow transporting and storing one or more cordless power tools while supplying suitable electrical charge for continuous or extended operation. 
     SUMMARY 
     Configurations and methods of wireless power transmission for cordless power tools are disclosed. Wireless power transmission for charging one or more cordless power tools may include a toolbox with an embedded transmitter capable of emitting RF waves for the generation of pockets of energy; a battery attached or embedded in the toolbox to supply power to the transmitter; a cable that may connect toolbox&#39;s battery to a suitable external power source for charging; and one or more cordless power tools which may include rechargeable batteries and receivers that may utilize pockets of energy for wireless charging or powering. 
     According to an embodiment, a toolbox may be used to carry and store one or more cordless power tools and related components, materials, or accessories. The disclosed toolbox may include a transmitter utilized for pocket-forming, where this transmitter may include two or more antenna elements, a RF integrated circuit, a communications module, and a microcontroller. The toolbox may also include a battery for powering the transmitter. A cable may be used to connect the toolbox to an external power source, such as a 120/220 AC volts outlet, to provide suitable charge to the battery. In operation, the transmitter embedded in the toolbox may generate and direct RF waves towards one or more receivers attached or embedded in one or more cordless power to wirelessly charge or at least extend the operation of the batteries incorporated in the cordless power tools. The receiver attached or embedded in the cordless power tools may include at least one antenna element, a rectifier, a converter, and a communications component. When the battery in toolbox is charged to a suitable level, toolbox may be disconnected from the AC outlet, and subsequently carried and positioned in a desired working area where one or more cordless power tools may require wireless charging. 
     In another embodiment, the toolbox with the embedded transmitter may be used within or outside a vehicle, where this toolbox can be connected to an external power source, in this case the vehicle&#39;s battery, for charging the battery incorporated in the toolbox. Transmitter in the toolbox may generate and direct RF waves towards one or more receivers attached or embedded in one or more cordless power tools to wirelessly charge or at least extend the operational period of the batteries incorporated in the cordless power tools. When the battery in toolbox is charged to a suitable level, toolbox may be disconnected from the car lighter socket, and subsequently carried and positioned in a desired working area where one or more cordless power tools may require wireless charging. 
     Yet in another embodiment, the transmitter may be configured in a vehicle&#39;s doors or windows, in which case, transmitter may be connected directly to the car lighter socket and may include a higher number of antenna elements which may allow to increase the power and reach of wireless charging for one or more cordless power tools. 
     In a further embodiment, a method for using the toolbox as a portable wireless charging device may include a charge level check for the battery incorporated in the toolbox, followed by connecting the toolbox to a suitable external power supply if necessary. If battery in toolbox is charged to a suitable level, communication module in the transmitter may identify one or more cordless power tools that may require wireless charging. Transmitter may subsequently generate and direct RF waves towards the identified power tools for charging or at least extending their batteries&#39; operational period. 
     The disclosed configurations and methods of wireless power transmission may include a toolbox with an embedded transmitter that may provide efficient and simultaneous wireless charging for one or more cordless power tools. This toolbox may be portable and may employ an incorporated battery to power up the transmitter to wirelessly charge one or more cordless power tools in construction sites where spare batteries or other power sources may be nonexistent or limited. Additional features and advantages can become apparent from the detailed descriptions which follow, taken in conjunction with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present disclosure can be better understood by referring to the following figures. The components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the disclosure. In the figures, reference numerals designate corresponding parts throughout the different views. 
         FIG. 1  illustrates a wireless power transmission for one or more cordless power tools using pocket forming. 
         FIG. 2  shows a component level embodiment of a transmitter which may be used in a wireless power transmission for cordless power tools. 
         FIG. 3  depicts a component level embodiment of a receiver which may be used in a wireless power transmission for cordless power tools. 
         FIG. 4  illustrates a configuration of a wireless power transmission which may include a transmitter embedded in a toolbox to wirelessly charge or power one or more cordless power tools. 
         FIG. 5  shows a configuration of a wireless power transmission where a portable toolbox with an embedded transmitter may be located within or outside a vehicle for wireless charging or powering of one or more cordless power tools. 
         FIG. 6  depicts a configuration of a wireless power transmission where a transmitter may be configured in one of the doors or windows of a vehicle for wireless charging or powering one or more power tools. 
         FIG. 7  illustrates a simplified flowchart of a wireless power transmission process which may be implemented for the wireless charging of one or more cordless power tools using a toolbox as a portable device. 
     
    
    
     DETAILED DESCRIPTION 
     The present disclosure is here described in detail with reference to embodiments illustrated in the drawings, which form a part here. Other embodiments may be used and/or other changes may be made without departing from the spirit or scope of the present disclosure. The illustrative embodiments described in the detailed description are not meant to be limiting of the subject matter presented here. 
     As used here, the following terms may have the following definitions: 
     “Pocket-forming” may refer to generating two or more RF waves which converge in 3-d space, forming controlled constructive and destructive interference patterns. 
     “Pockets of energy” may refer to areas or regions of space where energy or power may accumulate in the form of constructive interference patterns of RF waves. 
     “Null-space” may refer to areas or regions of space where pockets of energy do not form because of destructive interference patterns of RF waves. 
     “Transmitter” may refer to a device, including a chip which may generate two or more RF signals, at least one RF signal being phase shifted and gain adjusted with respect to other RF signals, substantially all of which pass through one or more RF antenna such that focused RF signals are directed to a target. 
     “Receiver” may refer to a device including at least one antenna element, at least one rectifying circuit and at least one power converter, which may utilize pockets of energy for powering, or charging an electronic device. 
     “Adaptive pocket-forming” may refer to dynamically adjusting pocket-forming to regulate power on one or more targeted receivers. 
       FIG. 1  illustrates a wireless power transmission  100  using pocket-forming. A transmitter  102  may transmit controlled Radio Frequency (RF) waves  104  which may converge in 3-d space. These RF waves  104  may be controlled through phase and/or relative amplitude adjustments to form constructive and destructive interference patterns (pocket-forming). Pockets of energy  106  may be formed at constructive interference patterns and can be 3-dimensional in shape, while null-spaces may be generated at destructive interference patterns. A receiver  108  may then utilize pockets of energy  106  produced by pocket-forming for charging or powering the battery  112  of a cordless power tool  110 , for example, a drill (as shown in  FIG. 1 ), a screwdriver, a circular saw, a nailer, a grinder, and the like, In some embodiments, there can be multiple transmitters  102  and/or multiple receivers  108  for powering various cordless power tools  110  at the same time. In other embodiments, adaptive pocket-forming may be used to regulate the power transmitted to cordless power tools  110 . 
       FIG. 2  illustrates a component level embodiment for transmitter  102  which may be used in wireless power transmission  100 . Transmitter  102  may include a housing  202 , at least two or more antenna elements  204 , at least one RF Integrated Circuit (RFIC)  206 , at least one digital signal processor (DSP) or micro-controller  208 , and one communications component  210 . Housing  202  can be made of any suitable material which may allow for signal or wave transmission and/or reception, for example plastic or hard rubber. Antenna elements  204  may include suitable antenna types for operating in frequency bands such as 900 MHz, 2.5 GHz or 5.8 GHz as these frequency bands conform to Federal Communications Commission (FCC) regulations part  18  (Industrial, Scientific and Medical equipment). Antenna elements  204  may include vertical or horizontal polarization, right hand or left hand polarization, elliptical polarization, or other suitable polarizations as well as suitable polarization combinations, Suitable antenna types may include, for example, patch antennas with heights from about ⅛ inch to about 8 inches and widths from about ⅛ inch to about 6 inches. Other antenna elements  204  types can be used, for example meta-materials, dipole antennas among others. 
     RFIC  206  may include a proprietary chip for adjusting phases and/or relative magnitudes of RF signals which may serve as inputs for antenna elements  204  for controlling pocket-forming. These RF signals may be produced using a power source  212  and a local oscillator chip (not shown) using a suitable piezoelectric material. Micro-controller  208  may then process information sent by a receiver through communications component  210  for determining optimum times and locations for pocket-forming. Communications component  210  may be based on standard wireless communication protocols which may include Bluetooth, Wi-Fi or ZigBee. In addition, communications component  210  may be used to transfer other information such as an identifier for the device or user, battery level, location or other such information. Other communications component  210  may be possible, including radar, infrared cameras or sound devices for sonic triangulation of the device&#39;s position. 
       FIG. 3  illustrates a component level embodiment for receiver  108  which can be used for wireless powering or charging a cordless power tool  110  as exemplified in wireless power transmission  100 . Receiver  108  may be integrated in cordless power tool  110  and may include a housing  302  where at least one antenna element  304 , one rectifier  306 , one power converter  308  and a communications component  310  may be included. Housing  302  can be made of any suitable material which may allow for signal or wave transmission and/or reception, for example plastic or hard rubber. Housing  302  may be an external hardware that may be added to different electronic equipment, for example in the form of cases, or can be embedded within electronic equipment as well. Antenna element  304  may include suitable antenna types for operating in frequency bands similar to the bands described for transmitter  102  from  FIG. 2 . Antenna element  304  may include vertical or horizontal polarization, right hand or left hand polarization, elliptical polarization, or other suitable polarizations as well as suitable polarization combinations. Using multiple polarizations can be beneficial in devices where there may not be a preferred orientation during usage or whose orientation may vary continuously through time, for example cordless power tool  110 . On the contrary, for devices with well-defined orientations, for example a two-handed video game controller, there might be a preferred polarization for antennas which may dictate a ratio for the number of antennas of a given polarization. Suitable antenna types may include patch antennas with heights from about ⅛ inch to about 6 inches and widths from about ⅛ inch to about 6 inches. Patch antennas may have the advantage that polarization may depend on connectivity, i.e., depending on which side the patch is fed, the polarization may change. This may further prove advantageous as receiver  108  may dynamically modify its antenna polarization to optimize wireless power transmission. 
     Rectifier  306  may include diodes or resistors, inductors or capacitors to rectify the alternating current (AC) voltage generated by antenna element  304  to direct current (DC) voltage. Rectifier  306  may be placed as close as is technically possible to antenna element  304  to minimize losses. After rectifying AC voltage, DC voltage may be regulated using power converter  308 . Power converter  308  can be a DC-DC converter which may help provide a constant voltage output to charge the battery  112  of cordless power tool  110 . Typical voltage outputs can be from about 5 volts to about 10 volts. In some embodiments, power converter  308  may include electronic switched mode DC-DC converters which can provide high efficiency. In such a case, a capacitor (not shown) may be included before power converter  308  to ensure sufficient current is provided. Lastly, a communications component  310 , similar to that of transmitter  102  from  FIG. 2 , may be included in receiver  108  to communicate with a transmitter or to other electronic equipment. 
     Referring now to  FIG. 4 , a configuration of wireless power transmission  100  may include a transmitter  102  embedded in a toolbox  402  to wirelessly charge or power one or more cordless power tools  110 , according to an embodiment. Toolbox  402  may be capable of storing and transporting a plurality of cordless power tools  110  and other related tools or components. Transmitter  102  may be embedded in a region or area of toolbox  402  suitable for transmitting RF waves  104  towards receiver  108  which may be attached or operatively coupled to the battery  112  of cordless power tool  110 . For example, transmitter  102  may be positioned at the top right corner of toolbox  402  housing (as shown in  FIG. 4 ) to direct RF waves  104  towards receiver  108  for the generation of pockets of energy  106  capable of wirelessly charging the battery  112  of cordless power tool  110 . 
     Toolbox  402  may also include a battery  404  which may be operatively coupled with transmitter  102  through a cable (not shown in  FIG. 4 ) for allowing the generation and transmission of RF waves  104  as required by the application. Simply put, battery  404  may function as a power source  212  for transmitter  102  as shown in  FIG. 2 . In an embodiment, toolbox  402  may be connected to an external power source  406  to charge battery  404  through a suitable cable  408 , while simultaneously powering transmitter  102  for the generation and transmission of RF waves  104  directed towards receiver  108  which can embedded or attached to cordless power tool  110 . External power source  406  source may include a 120/220 AC volts outlet, in which case toolbox  402  may include a suitable AC/DC converter (not shown in  FIG. 4 ) for converting AC voltage and supplying DC voltage to battery  404  for charging. 
     In another embodiment, when battery  404  is charged to a suitable level, toolbox  402  may be disconnected from external power source  406 , and subsequently carried and positioned in a desired working area where cordless power tool  110  may be used. In this case, transmitter  102  may receive power for the generation and transmission of RF waves  104  solely and directly from battery  404 . Charged battery  404  in toolbox  402  may provide enough charge to transmitter  102  for the generation of pockets of energy  106  within a power range of about 1 watt to about 5 watts, and within a working distance of about 5 ft. to about 20 ft. These power levels of pocket of energy  106  may be suitable for charging the battery  112  of cordless power tool  110  while in use, or at least extending the life of battery  112  during operation. In general, the power and range of the generated RF waves  104  may vary according to the number of antenna elements  204 , distribution, and size of transmitter  102 . A cordless power tool  110  not in use or in standby can also be charged by transmitter  102  embedded in toolbox  402 . 
       FIG. 5  shows another configuration of wireless power transmission  100  where the portable toolbox  402  may be located on or within a vehicle  502 , according to an embodiment. Vehicle  502  may be a private car or a service van commonly used by technicians having to perform field work or related activities. Similarly as in  FIG. 4 , toolbox  402  may be connected to external power source  406  for charging battery  404  and powering transmitter  102 . External power source  406 , in this case, may be the battery of vehicle  502 . Toolbox  402  may be operatively coupled to external power source  406  through a suitable connection that includes a car lighter socket  504  and cable  408 . In order to avoid draining the battery of vehicle  502 , engine  506  may be on or running when charging battery  404  or powering transmitter  102  in toolbox  402 . In an embodiment, transmitter  102  may generate and direct RF waves  104  towards the receivers  108  embedded or attached to one or more cordless power tools  110  for the wireless charging of batteries  112 . Transmitter  102  in toolbox  402  may wirelessly charge or power two or more cordless power tools  110  simultaneously or sequentially according to the power or application requirements. Transmitter  102  in toolbox  402  may also charge a spare battery  508  having a suitable receiver  108  attached. 
     In an embodiment, when battery  404  in toolbox  402  is charged to a suitable level, toolbox  402  can be disconnected from the car lighter socket  504  and placed at a location outside vehicle  502 . Transmitter  102  in toolbox,  402  may subsequently generate RF waves  104  which may wirelessly charge or at least extend the life of batteries  112  during the operation of cordless power tools  110 , in this case, transmitter  102  may be energized directly from the charged battery  404  in toolbox  402 . Surface area of the antenna array used in transmitter  102  embedded in toolbox  402  may range from approximately two in 2  to about 12 in 2  depending on the dimensions of toolbox  402 . 
       FIG. 6  illustrates a further configuration of wireless power transmission  100  where transmitter  102  may be configured in the doors or windows of vehicle  502 , according to an embodiment. Specifically, the antenna array of transmitter  102  may be configured to fit one window of vehicle  502  as shown in  FIG. 6  in which case, said antenna array may include between about 300 and about 600 antenna elements  204  distributed within a surface area that may vary between about 90 in 2  and about 160 in 2 . This increased number of antenna elements  204  and footprint of transmitter  102  may allow for a higher level of power distribution and reach of the emitted RF waves  104  as compared to the embodiment shown in  FIG. 5 . For example, transmitter  102  within the specified dimensions and number of antenna elements  204  may emit RF waves  104  capable of generating pocket of energy  106  between about 1 Watt and 10 Watts of power, and within a distance of about 30 ft. and about 50 ft. 
     In  FIG. 6 , transmitter  102  may be constantly and directly connected to an external power source  406  such as vehicle  502  battery via car lighter socket  504  and cable  408 . Engine  506  may be on or running when transmitter  102  is in operation in order to prevent draining the vehicle  502  battery. Transmitter  102  may generate and direct RF waves  104  towards the receivers  108  embedded or attached to one or more cordless power tools  110  for the charging of batteries  112 . Transmitter  102  may wirelessly charge or power two or more cordless power tools  110  simultaneously or sequentially according to the power or application requirements. Transmitter  102  may also wirelessly charge a spare battery  508  having a suitable receiver  108  attached. 
       FIG. 7  shows a simplified flowchart of a wireless power transmission process  700  that may′ be implemented for charging one or more cordless power tools  110  using toolbox  402  as a portable device. This process may be applicable to the embodiments of wireless power transmission  100  shown in  FIG. 4  and  FIG. 5 . 
     Wireless power transmission process  700  may begin by checking the charge levels of battery  404  embedded in toolbox  402 , at block  702 . This charge check may be performed by a control module included in toolbox  402  (not shown in  FIG. 4  and  FIG. 5 ) or by micro-controller  208  in transmitter  102 , which may be operatively connected to battery  404 . Different charging levels for battery  404  may be established for maintaining suitable operation. For example, minimum and maximum charging thresholds may be established at about 25% and 99% of total charge respectively. At block  704 , if battery  404  charge is below the minimum threshold or 25%, then toolbox  402  can be connected to external power source  406  using cable  408 , where external power source  406  may include vehicle  502  battery or a standard 120/220 AC volts outlet as explained in  FIG. 4  and  FIG. 5 . When battery  404  charge is at 99% or at least above 25%, toolbox  402  can be disconnected from external power source  406 , at block  706 . 
     If battery  404  is charged to a suitable level, specifically between about 25% and about 99%, then wireless power transmission process  700  may continue at block  708 , where communications component  210  in transmitter  102  may identify one or more cordless power tools  110  that may require wireless charging. Charging or powering priorities and other parameters such as power intensity and pocket-forming focus/timing may be established using a control module included in toolbox  402  (not shown in  FIG. 4  and  FIG. 5 ) or micro-controller  208  in transmitter  102 . For example, based on charging or powering priorities, transmitter  102  may be configured to first provide wireless charging to cordless power tools  110  in use, followed by cordless power tools  110  in standby, and lastly to spare batteries  508 . 
     After cordless power tools  110  are identified and charging priorities/parameters in transmitter  102  are set, transmission of RF waves  104  towards the designated cordless power tools  110  or spare batteries  508  can begin, at block  710 , where these RF waves  104  may generate pockets of energy  106  at receivers  108  for powering or charging one or more cordless power tools  110  and spare batteries  508  sequentially or simultaneously. 
     Using communications component  210 , transmitter  102  in toolbox  402  may continuously check if there are other cordless power tools  110  or spare batteries  508  that may require wireless charging or powering, at block  712 . If new or additional cordless power tools  110  or spare batteries  508  are identified, then transmitter  102  in toolbox  402  may wirelessly charge the identified cordless power tools  110  and spare batteries  508  according to the established charging priorities and parameters. If no further cordless power tools  110  are recognized by communications component  210  in transmitter  102 , then wireless power transmission process  700  may end. 
     While various aspects and embodiments have been disclosed, other aspects and embodiments are contemplated. The various aspects and embodiments disclosed are for purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated by the following claims.