Patent Publication Number: US-2019181668-A1

Title: Power supply circuit for electronic cigarette and electronic cigarette

Description:
This application claims all benefits accruing under 35 U.S.C. § 119 from China Patent Application No. 201620957092.7, filed on Aug. 26, 2016 in the China National Intellectual Property Administration, the content of which is hereby incorporated by reference. This application is a continuation-in-part under 35 U.S.C. § 120 of international patent application PCT/CN2017/098999 filed Aug. 25, 2017. 
     FIELD 
     The present disclosure relates to power source, particularly relates to a power supply circuit for an electronic cigarette and an electronic cigarette. 
     BACKGROUND 
     Small electronic devices, such as electronic cigarettes, need a battery for power supply. Conventional batteries provide a constant voltage after being mounted to the electronic devices. Therefore, voltages in series connections and parallel connections of a power supply circuit of the electronic device cannot be changed according to different voltage requirements of the electronic device. 
     Thus, there is room for improvement within the art. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Many aspects of the disclosure can be better understood with reference to the following drawings. The components in the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the disclosure. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views. 
         FIG. 1  is a circuit diagram of an embodiment of a power supply circuit with three branch power supply circuits. 
         FIG. 2  is a circuit diagram of an embodiment of a power supply circuit with two branch power supply circuits. 
     
    
    
     DETAILED DESCRIPTION 
     In order to make the above-mentioned objects, features and advantages of the present implementation more obvious, a detailed description of specific embodiments of the present implementation will be described in detail with reference to the accompanying drawings. A number of details are set forth in the following description so as to fully understand the present implementation. However, the present implementation can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the contents of the present implementation. Therefore, the present implementation is not to be considered as limiting the scope of the embodiments described herein. 
     Several definitions that apply throughout this disclosure will now be presented. 
     Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one skilled in the art. The terms used in a specification of the present implementation herein are only for describing specific embodiments, and are not intended to limit the present implementation. The terms “and/or” used herein includes any and all combinations of one or more of associated listed items. 
       FIG. 1  shows a circuit diagram of at least one embodiment of a power supply circuit. The power supply circuit is configured for electronic devices, such as electronic cigarette. The power supply circuit has a simple structure and a low cost. Referring to  FIG. 1 , the power supply circuit includes a first branch power supply circuit  110 , a second branch power supply circuit  120 , and a third branch power supply circuit  130 . Specifically, the first branch power supply circuit  110  includes a first power unit  112  and a first parallel maintaining switch  114  connected in series. The second branch power supply circuit  120  includes a second power unit  122 , a second parallel maintaining switch  124 , and a third parallel maintaining switch  126  connected in series. The third branch power supply circuit  130  includes a third power unit  132  and a fourth parallel maintaining switch  134  connected in series. 
     A first series maintaining switch  140  is electrically connected between the first branch power supply circuit  110  and the second branch power supply circuit  120 . One end of the first series maintaining switch  140  is electrically connected to a negative electrode of the first branch power supply circuit  110 , the other end of the first series maintaining switch  140  is electrically connected to a positive electrode of the second branch power supply circuit  120 . A second series maintaining switch  150  is electrically connected between the second branch power supply circuit  120  and the third branch power supply circuit  130 . One end of the second series maintaining switch  150  is electrically connected to a negative electrode of the second branch power supply circuit  120 , the other end of the second series maintaining switch  150  is electrically connected to a positive electrode of the third branch power supply circuit  130 . 
     The first parallel maintaining switch  114 , the second parallel maintaining switch  124 , the third parallel maintaining switch  126 , the fourth parallel maintaining switch  134 , and the first series maintaining switch  140 , the second series maintaining switch  150  are configured as follows: 
     When each of the first parallel maintaining switch  114 , the second parallel maintaining switch  124 , the third parallel maintaining switch  126 , and the fourth parallel maintaining switch  134  are close, each of the first series maintaining switch  140  and the second series maintaining switch  150  are open. Thus, the first power unit  112 , the second power unit  122 , and the third power unit  132  are connected in parallel for providing of a higher electric power. 
     Alternatively, when each of the first parallel maintaining switch  114 , the second parallel maintaining switch  124 , the third parallel maintaining switch  126 , and the fourth parallel maintaining switch  134  are open, each of the first series maintaining switch  140  and the second series maintaining switch  150  are close. Thus, the first power unit  112 , the second power unit  122 , and the third power unit  132  are connected in series for providing a higher voltage. 
     In at least one embodiment, according to different series connection directions, positive electrodes and negative electrodes of the first and the fourth parallel maintaining switches  114 ,  134  of the first and the third branch power supply circuits  110 ,  130 , which are on two sides of the power supply circuit, can be adjusted correspondingly. Referring to  FIG. 1 , the first branch power supply circuits  110  is on the left side, the first parallel maintaining switch  114  is electrically connected to a negative electrode of the first power unit  112 ; the third branch power supply circuits  130  is on the right side, the fourth parallel maintaining switch  134  is electrically connected to a positive electrode of the third power unit  132 . 
     When the series connection direction is changed, in the first branch power supply circuits  110  on the left side, the first parallel maintaining switch  114  can be electrically connected to a positive electrode of the first power unit  112 ; in the third branch power supply circuits  130  on the right side, the fourth parallel maintaining switch  134  can be electrically connected to a negative electrode of the third power unit  132 . 
     Meanwhile, connections of the first series maintaining switch  140  and the second series maintaining switch  150  are changed correspondingly. Specifically, one end of the first series maintaining switch  140  is electrically connected to a positive electrode of the first branch power supply circuit  110 , the other end of the first series maintaining switch  140  is electrically connected to a negative electrode of the second branch power supply circuit  120 . One end of the second series maintaining switch  150  is electrically connected to a positive electrode of the second branch power supply circuit  120 , the other end of the second series maintaining switch  150  is electrically connected to a negative electrode of the third branch power supply circuit  130 . 
     In at least one embodiment, circuits with series connections and parallel connections switching demands may include at least two branch power supply circuits. When there are two branch power supply circuits, each of the branch power supply circuits may include only one parallel maintaining switch. When there are three or more branch power supply circuits, the branch power supply circuits on two sides (such as the first branch power supply circuit  110  and the third branch power supply circuit  130 ) may include at least one parallel maintaining switch, the branch power supply circuit(s) in the middle (such as the second branch power supply circuit  120 ) may include at least two parallel maintaining switches. In this embodiment,  FIG. 1  illustrates that the first branch power supply circuit  110  and the third branch power supply circuit  130  respectively include one parallel maintaining switch, and the second branch power supply circuit  120  includes two parallel maintaining switches. 
     In at least one embodiment, the parallel maintaining switches and the series maintaining switches may be triodes and be controlled to open and close by a control unit. 
     Additionally, each of the branch power supply circuits may further include an anti-reverse unit in series connection with the power unit, which is configured to switch off the circuit when polarity reversal of the power units happens, thus to protect the circuit. The anti-reverse unit includes a triode and an anti-reverse MOSFET connected in series. In at least one embodiment, a model of the anti-reverse MOSFET can be but is not limited to AON6411. 
     In at least one embodiment, the power units can be rechargeable batteries, such as lithium batteries. The power units can be other kinds of batteries, such as alkaline dry cells, nickel metal hydride batteries, nickel-cadmium batteries, lead acid batteries, nickel iron batteries, nickel metal hydride batteries, zinc silver batteries, zinc nickel batteries, hydrogen-oxygen fuel cells, solar cells, etc. 
     The power supply circuit may include more branch power supply circuits other than the three branch power supply circuits  110 ,  120 ,  130 . Connections for the more branch power supply circuits can be similarly arranged as the connections of the three branch power supply circuits  110 ,  120 ,  130 . The power supply circuit may include less branch power supply circuits than three. 
     In another embodiment, the power supply circuit includes two branch power supply circuits, which are described below. 
       FIG. 2  shows a circuit diagram of at least one embodiment of a power supply circuit including a first power unit  210  and a second power unit  220 . An outgoing line of a positive electrode (+) of the first power unit  210  is set to be a positive output terminal  201  of the power supply circuit, an outgoing line of a negative electrode (−) of the second power unit  220  is set to be a negative output terminal  202  of the power supply circuit. A negative electrode (−) of the first power unit  210  is electrically connected to the negative output terminal  202  through a first switch unit  212 . A positive electrode (+) of the second power unit  220  is electrically connected to the positive output terminal  201  through a second switch unit  222 . A third switch unit  230  is electrically connected between the negative electrode (−) of the first power unit  210  and the positive electrode (+) of the second power unit  220 . 
     The first switch unit  212 , the second switch unit  222 , and the third switch unit  230  are configured as follows: 
     When each of the first switch unit  212  and the second switch unit  222  is close, and the third switch unit  230  is open. Thus, the first power unit  210  and the second power unit  220  are connected in parallel for providing a higher electric power. Alternatively, when each of the first switch unit  212  and the second switch unit  222  is open, and the third switch unit  230  is close. Thus, the first power unit  210  and the second power unit  220  are in connected series for providing a higher voltage. 
     In at least one embodiment, the first switch unit  212 , the second switch unit  222 , and the third switch unit  230  can be triodes, which are simple and easy to control. 
     Additionally, referring to  FIG. 2 , the first power unit  210  may be further electrically connected to a first anti-reverse unit  214  in series; the second power unit  220  may be further electrically connected to a second anti-reverse unit  224  in series. The first anti-reverse unit  214  and the second anti-reverse unit  224  can be configured to switch off the circuit when polarity reversal of the power units happens, thus to protect the circuit. Each of the first anti-reverse unit  214  and the second anti-reverse unit  224  includes a triode and an anti-reverse MOSFET connected in series. In at least one embodiment, a model of the anti-reverse MOSFET can be but is not limited to AON6411. 
     Additionally, referring to  FIG. 2 , the power supply circuit may further include a control unit  240 . The control unit  240  is electrically connected to and is configured to control the first switch unit  212 , the second switch unit  222 , and the third switch unit  230 . The control unit  240  can be but is not limited to a single chip microcomputer (SCM). The single chip microcomputer is electrically connected to and is configured to control the first switch unit  212 , the second switch unit  222 , and the third switch unit  230  through an input output interface. 
     In at least one embodiment, the first power unit  210  and the second power unit  220  can be batteries, such as lithium batteries. The first power unit  210  and the second power unit  220  can be other kinds of batteries, such as alkaline dry cells, nickel metal hydride batteries, nickel-cadmium batteries, lead acid batteries, nickel iron batteries, nickel metal hydride batteries, zinc silver batteries, zinc nickel batteries, hydrogen-oxygen fuel cells, solar cells, etc. In other embodiments, the power supply circuit can be a power unit for forming a cascade power supply circuit. 
     The power supply circuit may switch the power units to be electrically connected in parallel and in series through switch units. Therefore, the power supply circuit can be widely and conveniently used. 
     It is to be understood, even though information and advantages of the present embodiments have been set forth in the foregoing description, together with details of the structures and functions of the present embodiments, the disclosure is illustrative only; changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the present embodiments to the full extent indicated by the plain meaning of the terms in which the appended claims are expressed.