Patent Publication Number: US-2022211373-A1

Title: Surgical instrument and battery pack thereof

Description:
CROSS-REFERENCE OF RELATED APPLICATIONS 
     The application is a continuation application of International Application No. PCT/CN2020/115563 filed on Sep. 16, 2020, which is hereby incorporated by reference in its entirety. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates to the technical field of medical instrument, and in particular to a battery-powered surgical device and the battery pack thereof. 
     BACKGROUND 
     More and more surgical instruments are powered by the battery pack comprising at least one battery unit. Such instruments comprise a variety of electric tools and may be used in various surgical environments. Surgical instruments may comprise staplers, cutters, graspers, suturing devices, RF cutters/coagulators, ultrasonic cutters/coagulators, laser cutters/coagulators, and other instruments that require battery power. For example, a stapler is a medical device that may be used in place of suturing manually, and is a surgical instrument that may be used to cut off and anastomose tissues by using titanium staples. With the advancement of electric stapler technology and the widespread promotion of its clinical application, the advantages of the electric stapler technology in clinical surgery have been recognized by more and more doctors. Compared with the traditional manual stapler, the electric stapler needs to be used with a power supply device, for example, a common lithium battery may be used for power supply. 
     Due to the structural principle characteristics of the lithium battery, the power dissipation of the lithium battery occurs during a storage process, and the electric stapler is required to have a certain storage validity period. Therefore, when the lithium battery is designed, the amount of the electric power in the lithium battery often exceeds the electric power required in actual use of the electric stapler. Therefore, after the use of the electric stapler, the amount of the power left in the lithium battery is usually still sufficient. If the lithium battery is improperly treated, it may cause explosion or fire and other hazards. Therefore, how to safely and harmless treat the lithium battery after use becomes an urgent problem to be solved, which affects a large-scale application of the electric staplers. 
     In the prior art, when the lithium battery is mounted in the battery compartment of the electric stapler, a protruding portion in the battery compartment will be connected to the discharge circuit in the battery device, thus the power in the lithium battery is consumed in a relatively small current through the discharge circuit, while outputting a large current through the electronic control circuit of the electric stapler to supply the DC motor to achieve a desired forward and reverse operation. After the lithium battery is taken out from the battery compartment, the lithium battery continues to be discharged through the discharge circuit, and the amount of the power of the lithium battery may be reduced to a safe threshold range within a predetermined time. However, in the prior art, the lithium battery of the electric stapler is discharged while working, and the working voltage of the motor usually has a lower limit and an upper limit, and when the electric stapler is fired at thick tissues, the lithium battery needs to provide an very high working current instantaneously, and the lithium battery is limited by an inherent design output power, which inevitably leads to the instantaneous and rapid decrease of the potential difference between the positive electrode and negative electrode at the output terminals of the lithium battery. When the potential difference between the positive electrode and negative electrode at the output terminal of the lithium battery is reduced to less than the lower limit of the motor&#39;s working voltage, the motor stops running, and the electric stapler is not able to complete the desired cutting and suturing function. 
     SUMMARY 
     Therefore, the technical problem to be solved by the present disclosure is how to overcome the defect in the prior art, in which the potential difference between the positive electrode and negative electrode of the battery output terminals is prone to be lower than the lower limit of the working voltage of the motor when powering the motor, which makes it difficult for the motor to operate normally. Therefore, the present disclosure is to provide a battery pack in which the potential difference between the positive electrode and negative electrode of the battery output terminals is less likely reduced to be less than the lower limit of the working voltage of the motor when powering the motor, and a surgical instrument powered by the battery pack. 
     In order to solve the above technical problem, according to one aspect of the present disclosure, the present disclosure provides a surgical instrument, comprising: a handle assembly, having a protruding portion; and a battery pack, detachably assembled on the handle assembly, and operatively coupled to the protruding portion, and having at least one battery unit; wherein, the battery pack comprises at least one discharging system comprising: a discharge element, and a switching member, operable to electrically connect the discharge element to the battery unit of the battery pack to form a discharge circuit; wherein, the switching member has an initial open state, in which the discharge circuit is non-conductive; an intermediate open state, in which the switching member cooperates with the protruding portion to make the discharge circuit non-conductive, and a closed state, in which the switching member is released from the protruding portion to make the discharge circuit conducting. 
     Furthermore, the battery pack further comprises a mounting body that comprises a housing, and a frame; wherein, the battery unit is assembled on the frame, and the housing covers the frame, and the frame further comprises a recess adapted for receiving the protruding portion. 
     Furthermore, a battery dock is provided on the handle assembly for receiving the battery pack, and the protruding portion is arranged therein. 
     Furthermore, the discharging system further comprises a discharging circuit board, on which the discharge element is arranged, and the switching member is configured to be at least one conductive movable member with at least part operably movable, and 
     one end of the movable member is fixed on the discharging circuit board and electrically connected to the discharge element, and the other end thereof is operably connected to the discharge element electrically. 
     Furthermore, at least part of the movable member is an elastic member. 
     Furthermore, when the switching member is in the intermediate open state, the protruding portion forces the movable member at a position where the movable member is in non-conductive connection with the discharge element. 
     Furthermore, an aperture is arranged on the discharge circuit board, adapted for receiving at least a portion of the switching member. 
     Furthermore, the movable member comprises a fixed portion, a movable portion, operably to be electrically connected to the discharge element, and a transition portion, arranged between the fixed portion and the movable portion. 
     Furthermore, when the switching member is in the initial open state, the movable portion of the movable member abuts against a side wall of the aperture of the discharge circuit board, and is non-conductively connected to the discharge element. 
     Furthermore, the discharging circuit board is arranged on a side wall of the recess of the frame of the battery pack. 
     Furthermore, the switching member comprises a blocking member and a conductive member, and the blocking member and/or the conductive member are/is operable to switch the switching member between the initial open state, the intermediate open state and the closed state. 
     Furthermore, the blocking member is adapted for causing the switching member to be in the initial open state, and is operated by the protruding portion to be disabled from blocking the switch member, so as to cause the switching member to be in the intermediate open state. 
     Furthermore, the switching member is arranged on a proximal side of the recess of the frame of the battery pack, and is electrically connected to the discharge element. 
     Furthermore, the conductive member comprises separable conductive elastic pieces, wherein when the switching member is in the initial open state, the blocking member is arranged between free ends of the conductive elastic pieces to isolate the conductive elastic pieces from each other. 
     Furthermore, the switching member comprises a blocking member, and a conductive member having a separable conductive elastic piece, wherein when the switching member is in the initial open state, the blocking member is arranged between free ends of the conductive elastic pieces to isolate the conductive elastic pieces from each other. 
     Furthermore, the blocking member is actuated by the protruding portion to be released from the conductive member. 
     Furthermore, when the switching member is in the intermediate open state, the protruding portion is respectively in contact with the free ends of the conductive elastic pieces, so as to isolate the conductive elastic pieces from each other. 
     Furthermore, when the free ends of the conductive elastic members are engaged with each other, the switching member is switched to the closed state, and the discharge circuit is conducting. 
     Furthermore, the switching member comprises a first switch and a second switch, and the first switch and/or the second switch are/is operable to be electrically connected with the discharge element, so as to switch the switching member between the initial open state, the intermediate open state and the closed state. 
     Furthermore, the blocking member is configured as a first switch, and the conductive member is configured as a second switch. 
     Furthermore, the first switch is operable to control the second switch. 
     Furthermore, the first switch is configured as a self-locking switch. 
     Furthermore, the second switch is an electronic switch. 
     Furthermore, the second switch is a photoelectric switch. 
     Furthermore, a fin portion is arranged on the protruding portion and is operable to control the first switch and/or the second switch. 
     Furthermore, when the switching member is in the initial open state, the first switch is switched off and the second switch is not conductive. 
     Furthermore, when the switching member is in the intermediate open state, the first switch is turned on through the fin portion of the protruding portion, and the second switch is remained to be closed through the fin portion. 
     Furthermore, when the switching member is in the closed state, the first switch and the second switch are both conductive, allowing the discharge circuit to be conductive. 
     Furthermore, the switching member comprises a normal-close switch, the state of which is depended on a stop member, wherein the stop member is operated to switch the switching member between the initial open state, the intermediate open state, and the closed state. 
     Furthermore, the blocking member is configured as a stop member, and the conductive member is configured as a normal-close switch. 
     Furthermore, the stop member is a stop plate. 
     Furthermore, a tip is arranged on the protruding portion, and operably to disable the stop member from blocking, so as to switch the switching member to the intermediate open state. 
     Furthermore, when the switching member is in the initial open state, the stop member abuts against the normal-close switch to switch off the normal-close switch. 
     Furthermore, when the switching member is in the intermediate open state, the protruding portion disables blocking function of the stop member, and the protruding portion abuts against the normal-close switch to keep the normal-close switch off. 
     Furthermore, when the switching member is in the closed state, the protruding portion is released from the normal-close switch to switch it to the closed state, allowing the discharge circuit to be conductive. 
     According to another aspect of the present disclosure, it provides a battery pack comprising at least one battery unit, further comprising at least one discharging system having: a discharging element, and a switching member, operably to be in electrical connection with the discharging element to the battery unit of the battery pack to form a discharge circuit; the switching member has an initial open state, in which the discharge circuit is non-conductive, an intermediate open state, in which the switching member is operated to cause the discharge circuit to be non-conductive, and a closed state, in which the switching member is operated to allow the discharge circuit to be conductive. 
     Furthermore, the battery pack comprises a mounting body, provided with a housing, and a frame, wherein, the battery unit is assembled on the frame and the housing covers the frame, and the frame further comprises a recess suitable for receiving the protruding portion. 
     Furthermore, the discharging system further comprises a discharging circuit board provided with the discharging element, and the switching member is configured to be at least one conductive movable member, and at least portion of the movable member is operated to move, and one end of the movable member is fixed on the discharging circuit board and electrically connected to the discharge element, and the other end of the movable member is operated to be electrically connected to the discharge element. 
     Furthermore, the switching member comprises a blocking member and a conductive member, and the blocking member and/or the conductive member are/is operable to switch the switching member between the initial open state, the intermediate open state and the closed state. 
     Furthermore, the blocking member is adapted for making the switching member to be in the initial open state, and is operably to be functionally disabled from blocking so as to switch the switching member to the intermediate open state. 
     Furthermore, the switching member is arranged on a proximal side of the frame of the battery pack, and is electrically connected to the discharge element. 
     Furthermore, the conductive member comprises separable conductive elastic pieces, and when the switching member is in the initial open state, the blocking member is arranged between free ends of the conductive elastic pieces to isolate the conductive elastic pieces from each other. 
     Furthermore, the switching member comprises a blocking member, and a conductive member that comprises a separable conductive elastic piece, and when the switching member is in the initial open state, the blocking member is arranged between free ends of the conductive elastic pieces to isolate the conductive elastic pieces from each other. 
     Furthermore, the switching member comprises a first switch and a second switch, and the first switch and/or the second switch are/is operably to be electrically connected with the discharging elements, so as to switch the switching member between the initial open state, the intermediate open state, and the closed state. 
     Furthermore, the blocking member is configured as a first switch, and the conductive member is configured as a second switch. 
     Furthermore, the switching member comprises a normal-close switch and a stop member, the state of which is depended on the stop member, wherein the stop member is operated to switch the switching member between the initial open state, the intermediate open state, and the closed state. 
     Furthermore, the blocking member is configured as a stop member, and the conductive member is configured as a normal-close switch. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In order to more clearly describe the technical solutions in the specific embodiments of the present invention or in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced hereinafter. Apparently, the appended drawings described below represents some embodiments of the present invention, and other drawings may be obtained on the basis of these drawings by a person skilled in the art without making creative efforts. 
         FIG. 1  is a schematic structural view of an electric surgical instrument provided by an embodiment of the application. 
         FIG. 2  is a schematic structural view the electric surgical instrument handle assembly in  FIG. 1 . 
         FIG. 3  is a schematic structural view of the battery pack in  FIG. 1 . 
         FIG. 4  is a schematic structural view of an interior of the battery pack in  FIG. 3 . 
         FIG. 5  is a working principle view of an electrical circuit of the electric surgical instrument communicating with the discharge circuit. 
         FIG. 6  is a schematic structural view of a circuit board of an embodiment of the application. 
         FIG. 7  is a sectional view of the battery pack of an embodiment of the application. 
         FIG. 8  is a sectional view of the battery pack of an embodiment of the application, in which the protruding portion is in contact with the switching member. 
         FIG. 9  is a sectional view of the battery pack of an embodiment of the application, in which the protruding portion is separated from the switching structure. 
         FIG. 10  is a schematic structural view of an embodiment of the application having one circuit board. 
         FIG. 11  is a schematic structural view of an elastic piece of an embodiment of the application. 
         FIG. 12  is a schematic structural view an elastic piece of another embodiment of the application. 
         FIG. 13  is a sectional view of a battery pack of another embodiment of the application. 
         FIG. 14  is a sectional view of the battery pack of another embodiment of the application, in which the protruding portion abuts against the blocking member. 
         FIG. 15  is a sectional view of the battery pack in another embodiment of the application, in which the protruding portion pushes the blocking member until to fall. 
         FIG. 16  is a schematic structural view the battery pack of another embodiment of the application, in which free ends of the conductive elastic strip are in contact with each other. 
         FIG. 17  is a schematic structural view of a conductive member of another embodiment of the application. 
         FIG. 18  is a schematic view of a blocking member of another embodiment of the application. 
         FIG. 19  is a schematic structural view of a discharging circuit board according to another embodiment of the application. 
         FIG. 20  is a schematic structural view a protruding portion of another embodiment of the application. 
         FIG. 21  is a schematic structural view of a discharging circuit board of a further embodiment of the application. 
         FIG. 22  is a sectional view of a battery pack of a further embodiment of the application. 
         FIG. 23  is a sectional view of the battery pack of another embodiment of the application, in which a protruding portion abuts against a blocking member. 
         FIG. 24  is a schematic structural view of a further embodiment of the application, in which a protruding portion abuts against a blocking member. 
         FIG. 25  is a schematic structural view of a protruding portion of a further embodiment of the application. 
         FIG. 26  is a sectional view of a battery pack of a further embodiment of the application. 
         FIG. 27  is a sectional view of a battery pack in a direction of A-A in  FIG. 26 , illustrating a protruding portion abuts against the blocking member. 
         FIG. 28  is a sectional view in a direction of A-A in  FIG. 26 , illustrating a protruding portion abutting against a stop member until breaking. 
         FIG. 29  is a schematic structural view in a direction of A-A in  FIG. 26 , illustrating a battery pack is used. 
     
    
    
     DETAILED DESCRIPTION 
     The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the drawings. Apparently, the described embodiments only represent part of but not all of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by a person skilled in the art without making creative efforts fall within the scope of the present invention. 
     In addition, the technical features involved in the different embodiments of the present disclosure described below may be combined with each other as long as they do not conflict with each other. 
     In the various embodiments of the present disclosure, the terms “distal end/distal side/distal portion” refers to the end/side/portion of the surgical instrument away from an operator during operation, and the terms “proximal end/proximal side/proximal portion” refers to the end/side/portion of the surgical instrument close to the operator during operation. 
     A number of embodiments of the present disclosure relate to battery-powered surgical instruments and battery packs that comprise structures that is beneficial for shipping, storage, and treatment. For example, in an embodiment of the present disclosure, the battery pack may comprise at least one battery located in a housing which defines a cavity. The battery pack may have a discharging system arranged in the cavity, the discharging system includes a switching member and a discharge element, and the switching member may switched among a first state, a second state, and a third state. The surgical instrument used in combination with the battery pack may comprise a protruding portion, a battery dock, or other battery pack receiving/connecting portion. The protruding portion may be arranged on a base assembly of the instrument, and may also be arranged on a grip portion of the instrument handle assembly. Before getting connected to the surgical instrument, the switching member is in a first state, such as an initial open state. When the battery pack is connected to the surgical instrument, the protruding portion may be used to operate the switching member to reach a second state, such as an intermediate open state. The switching member is operated by the protruding portion to change its position so as to be in a second state, such as an intermediate open state. The protruding portion is removed from the switching member to reach a third state, such as a closed state. When the switching member is in a closed state, the anode, the cathode and the discharge element of the battery unit are electrically connected to form a discharge circuit. In some embodiments, the discharge element is a resistance element. After the battery pack is removed from the surgical instrument, the power is consumed through the discharge circuit from the battery units. In some embodiments, the battery pack also comprises a plurality of such discharging systems. 
     Before describing the embodiments of the battery unit, the battery, the battery pack and related surgical instrument, embodiments of the surgical instruments powered by batteries are firstly described in details in the present disclosure. Although the surgical instrument described herein comprise electrosurgical instruments for cutting and suturing, it should be understood that the battery units and battery packs described herein may be used in combination with any suitable type of electrosurgical instruments, such as cutters, holders, suturing devices, RF cutter/coagulators, ultrasonic cutters/coagulators, laser cutters/coagulators, etc. 
       FIG. 1  is a schematic structural view of an example of a surgical instrument  100 . The embodiment as shown is an endoscopic instrument. In general, the example of the surgical instrument  100  described herein is an endoscopic surgical cutting and stapling instrument. However, it should be indicated that according to other embodiments, the surgical instrument may also be a non-endoscopic surgical cutting and stapling instrument, such as an open surgical instrument for open surgery. 
     Specifically, the surgical instrument  100  shown in  FIG. 1  comprises a handle assembly  80 , an elongated body  10 , and an end effector  70 , wherein the elongated body  10  extends distally from the handle assembly  80 , and the end effector  70  is assembled on a distal portion of the elongated body  10 , in which the end effector  70  is adapted to perform specific surgical operations, such as clamping, suturing/stapling, cutting, etc. on tissues. As further shown in  FIG. 1 , the handle assembly  80  comprises a trigger  81  and a grip portion  82 . When the trigger  81  is pulled towards the gripping portion  82 , jaws of the end effector  70  may be closed. In addition, the trigger  81  may also be configured to control the output of a power supplier of the surgical instrument  100 . 
     It should be noted that although one of the embodiments of the surgical instrument  100  described herein is configured with an end effector  70  for cutting anastomosing tissue, in alternative embodiments, other technologies for cutting or anastomosing tissue may also be used. For example, end effectors that applies RF energy or adhesives to anastomose tissues may also be used. 
     As further shown in  FIG. 1 , the surgical instrument  100  according to one of the embodiments of the present disclosure further comprises a rotating knob  86  assembled on the distal portion of the handle assembly  80  and fixed with the proximal portion of the elongated body  10 . When the rotating knob  86  is operated to rotate about a longitudinal axis C of the surgical instrument  100 , the elongated body  10  and the end effector  70  are rotated accordingly. In addition, the surgical instrument  100  according to the one of embodiments of the present disclosure further comprises a articulation knob  87 , which is rotatably mounted on the rotating knob  86 , adapted e for articulating the end effector  70  when being operated. 
     With further reference to  FIG. 2 , it shows an internal structure of the handle assembly  80  of the surgical instrument  100  provided by one of the embodiments. The power supplier  85  is arranged in a housing  83 , providing power for the surgical instrument  100 . A control device  853  is also disposed inside housing  83  to control the output of the power supplier  85  to output power, and the control device  853  may be a control circuit board. The power supplier  85  used for the surgical instrument  100  may be a motor of any form, as long as it may meet the specific output form and requirements of the surgical instrument  100 . For example, the power supplier  85  of the surgical instrument  100  in this embodiment adopts a DC brush motor, and the functions of electric firing (forward) and electric retreat of the surgical instrument  100  may be achieved through the forward and reverse rotation of the motor. Certainly, the power supplier  85  may also adopt other types of motors such as a DC brushless motor. 
     The handle assembly  80  also comprises an actuation mechanism  89  that comprises a gear assembly  891 , a rack assembly  892 , and a drive rod. The gear assembly  891  is connected to an output of the power supplier  85  and the rack assembly  892  respectively, and a distal portion of the drive rod is arranged in the elongated body  10 , and a proximal portion of the drive rod is coupled with the rack assembly  892 . In other embodiments, the power supplier  85  is further provided with a gear box  852 , and the motor  851  is coupled to the gear assembly  891  through the gear box  852  so as to provide power for the surgical instrument  100 . 
     As shown in  FIG. 1  and  FIG. 2 , the handle assembly  80  of the surgical instrument  100  according to the embodiment may allow at least one battery pack  50  to be received therein. In one of the embodiments, a battery dock  88  for receiving the battery pack  50  is arranged on the handle assembly  80 . The battery pack  50  is detachably assembled in the battery dock  88 . The battery pack  50  may include a single battery or a plurality of batteries arranged in a series and/or parallel configuration.  FIG. 3  and  FIG. 4  show the specific structure of the battery pack  50 , comprising at least one battery unit  53  and a mounting body adapted for receiving the battery unit  53 . As shown in  FIG. 3  and  FIG. 4 , the mounting body comprises a housing  51 , a frame  54  and a cover  52 ; the housing  51  is sleeved on an outside of the frame  54 , and the battery unit  53  is assembled on the frame  54 . A plurality of battery units  53  may be arranged in series and/or in parallel configuration. For example, when there are two or more battery units  53 , the battery units  53  are connected by conductors  55 , such that the plurality of battery units  53  are connected in series. In this embodiment, there are four battery units  53  connected in series. Two battery units  53  at two ends of the series are respectively provided with output terminals  533 . Correspondingly, the cover  52  is provided with an aperture  532  allowing the output terminal  533  to pass through. A conductive terminal  854  disposed on the control device  853  is operatively in electrical connection to the output terminal  533  of the battery pack  50 , as shown in  FIG. 2  and  FIG. 5 , so as to provide power to the surgical instrument  100 . 
     In addition, a base assembly  84  is fixed or detachably arranged in the battery dock  88 . When the battery pack  50  is assembled and received within the battery dock  88 , at least part of the base assembly  84  is coupled to the battery pack  50 . In other embodiments, a variety of other structures may be used to achieve functions of the base assembly  84 . For example, in one example, the base assembly  84  comprises a protruding portion  841  that is operably received by the battery pack  50 . For example, a recess  541  is arranged in the frame  54  of the mounting body of the battery pack  50 , which is adapted for receiving the protruding portion  841  of the base assembly  84 . Preferably, the protruding portion  841  is arranged perpendicular to the base assembly  84  and is located in a center of the battery base to facilitate insertion into the recess  541  of the frame  54  of the battery pack  50 . 
     In addition, as shown in  FIG. 3 , the housing  51  of the battery pack  50  is also provided with a mounting member  511 , and a fixing protrusion  512  is arranged on the mounting member  511 . The battery pack  50  is detachably mounted in the battery dock  88  of the handle assembly  80  through the mounting member  511 , the fixing protrusion  512  is adapted for fixing a relative position of the battery pack  50  and the battery dock  88 . 
     Furthermore, the battery pack  50  of one of the embodiments of the present disclosure further comprises a discharging system  20 , adapted for conducting discharging of the battery pack  50 , releasing the power of the battery units  53  of the battery pack  50  down to a safe threshold. The discharging system  20  comprises a switching member  22  and a discharge element  21  disposed on the discharging circuit board  23 . The discharge element  21  may be a resistance element, and the resistance element may be any suitable resistance element having any suitable resistance and/or impedance. A terminal  531  is further disposed on the discharging circuit board  23  (for example, as shown in  FIG. 6  and  FIG. 19 ), which is adapted to be electrically connected to the terminal  533  of the battery unit  53 , so as to operatively connect the discharging system  20  and the battery unit  53  electrically. The switching member  22  has an initial open state, an intermediate open state, and a closed state. For example, when the switching member  22  is in the initial open state or the intermediate open state, the discharging element  21  is not electrically connected to the battery unit  53 ; when the switching member  22  is in the closed state, the discharging element  21  is electrically connected to the battery unit  53  of the battery pack  50 .  FIG. 5  shows part of the circuit principle of the battery unit  53 , the discharging system  20  and the control device  853  in the battery pack  50 . 
     When the battery pack  50  is in the initial unused state, the switching member  22  is positioned in the initial open state, and the discharge circuit is not conductive, forming the first state of the discharging system  20 ; and after the battery pack  50  is assembled in the handle assembly  80  of the surgical instrument  100 , the switching member  22  is still operated in the open state, that is to say, the intermediate open state, and the discharge circuit is non-conductive, forming a second state of the discharging system  20 ; after the battery pack  50  is used, being detached from the surgical instrument  100 , the switching member  22  is operated to switch to the turn-on state, and the discharge circuit is conducted, forming a third state of the discharging system  20 . When the battery pack  50  has been fully discharged, it may be treated as non-hazardous waste. The structure of the discharging system  20  will be described in detail with reference to specific embodiments hereafter. 
     Embodiment 1 
       FIGS. 6 to 12  show a specific example of a battery pack  50  and a discharging system  20  thereof provided by the present disclosure, where the discharging system  20  comprises a switching member  22 , one end of which is fixed to the discharging circuit board  23 , being electrically connected to the discharge element  21 . The switching member  22  has an initial open state, an intermediate open state that may be operated, and a closed state, which correspond to the first state, the second state, and the third state of the discharging system  20 , respectively. The discharging system  20  of one of the embodiments will be described with reference to specific structures. 
     As shown in  FIG. 7  specifically, in the present embodiment, the discharging circuit board  23  is disposed on a side wall of the recess  541  of the frame  54  of the battery pack  50 . It should be understood that the discharging circuit board  23  may also be arranged on other places of the battery pack  50  for convenient operation. The switching member  22  is specifically configured as a movable member that is conductive, at least part of the movable member may be operated to move, and at least part of the movable member may be an elastic part, and specifically may be an elastic piece  220 , as shown in  FIG. 6  and  FIG. 7 , an aperture  233  is disposed in the discharging circuit board  23 , and at least part of the elastic piece  220  is disposed in the aperture  233 . Furthermore, the elastic piece  220  comprises a fixed portion  220   b  which is fixed in the discharging circuit board  23  and in electrical connection with the discharge element  21 ; a movable portion  220   a  operably to be connected to the discharging circuit board  23 , and operably to be electrically connected to the discharge element  21 ; and a transition portion  220   c  which formed between the fixed portion  220   b  and the movable portion  220   a  (as shown in  FIG. 11 ). The movable portion  220   a  of the elastic piece  220  may be operated to change the position thereof, such that the switching member  22  may be operated to switch between the initial open state, the intermediate open state, and the closed state. 
     Specifically, when the battery pack  50  is in the initial unused state, the switching member  22  is positioned in the initial open state, i.e. the movable portion  220   a  of the elastic piece  220  bias against the proximal wall of the aperture  233  of the discharging circuit board  23 , as shown in  FIG. 7 , where the movable portion  220   a  of the elastic piece  220  is not in electrical communication with the discharge element  21 , the discharge circuit is not conducting, which forms the first state of the discharging system  20 . 
     When the battery pack  50  is assembled in the battery dock  88  of the surgical instrument  100 , the protruding portion  841  is inserted into the recess  541  along an extending direction of the recess  541 , and the switching member  22  is operated to be switched to the intermediate open state, i.e., a transition portion  220   c  of the elastic piece  220  is actuated by the protruding portion  841  so as to drive the movable portion  220   a  to pass through the aperture  233  along the proximal wall thereof, and the movable portion  220   a  is biased by the protruding portion  841  so as to be disconnected with the discharging circuit board  23 , such that the switching member  22  is maintained to be positioned in the intermediate open state, and where the discharge circuit is non-conductive, forming the second state of the discharging system  20 , as shown in  FIG. 8 . It should be understood that the aperture  233  provides space, allowing at least part of the switching member  22  to move, such that at least part of the switching member  22  may be operated to move therein, and to be pass through as well. Therefore, the aperture  233  may also be configured in other shapes, such as a groove, a special-shaped groove, a special-shaped hole, etc. 
     When the surgical instrument  100  completes the surgical operation, the battery pack  50  is removed from the surgical instrument  100 , and the protruding portion  841  is removed from the recess  541  as well. Under elastic force provided by the transition portion  220   c,  the movable member  220   a  of the elastic piece  220  is moved towards the discharging circuit board  23  and contacted with the discharging circuit board  23 , so as to be further electrically connected with the discharge element  21 , such that, the switching member  22  is switched in the closed state, and the discharge circuit is conducting, forming the third state of the discharging system  20 , as shown in  FIG. 9 . It should be understood that the protruding portion  841  may also be arranged on the base assembly  84  or the grip portion of the handle assembly  80 . 
     Furthermore, as shown in  FIG. 11  and  FIG. 12 , a guide surface may be arranged on the movable portion  220   a  of the elastic piece  220 . When the transition portion  220   c  is operated, the guide surface has a guiding effect for the smooth position transition of the movable portion  220   a,  which is convenient for the movable member  220   a  to enter the aperture  233  smoothly. 
     It should be understood that the battery pack  50  may comprise at least one discharging systems  20  described in one of the embodiments. For example, one discharging circuit board  23  may be arranged on the side wall of the recess  541 , as shown in  FIG. 10 , or two discharge circuit boards  23  may be arranged on the side walls of the recess  541  in a symmetrical or asymmetric manner, as shown in  FIGS. 7-9 , other arrangement may be set, and specifically, the discharge circuit board may also be arranged on a proximal side of the recess  541 . It should be understood that a discharge speed of the battery pack  20  may be increased for rapidly discharging by using a plurality of discharging systems  20  to discharge simultaneously. 
     Furthermore,  FIG. 11  shows a specific structure of the elastic piece  220 . The elastic piece  220  comprises a fixed portion  220   b  and a movable portion  220   a,  and a transition portion  220   c  arranged therebetween. 
     A certain angle is formed by the fixed portion  220   b  and the transition portion  220   c.  For example, the fixed portion  220   b  may be arranged perpendicular to the transition portion  220   c;  the movable portion  220   a  and the transition portion  220   c  are also arranged with a certain angle, for example, an acute angle is formed between the movable portion  220   a  and the transition portion  220   c,  facilitating the elastic piece  220  to be moved to the corresponding position. Certainly, the movable portion  220   a  and the transition portion  220   c  of the elastic piece  220  may also be arranged in other manners for easy to be operated. 
     Alternatively, for example, as shown in  FIG. 12 , the transition portion  620   c  of the elastic piece  620  comprises a bent portion  620   d.  Such arrangement of the bent portion  620   c  weakens the rigidity of the transition portion  620   c,  which makes it easier for the elastic piece  620  to be operated to move, such that bias force applied during operation is reduced. It should be understood that the transition portion of the elastic piece in this embodiment may also be designed into other structures with weakening effect. 
     Embodiment 2 
       FIGS. 13 to 19  show the specific structures of the surgical instrument  100 , the battery pack  50  and the discharging system  20  in an alternative embodiment of the present disclosure, in which the switching member  22  of the discharging system  20  is arranged at a proximal side of the recess  541  of the frame of the battery pack  50 , or the switching member  22  may also be arranged in other ways, for example, it may also be arranged on the side wall of the recess  541  to be electrically connected to the discharge element  21 , and the discharging circuit board  23  may be arranged between the frame  54  and the housing  51 . 
     Referring to  FIG. 13 , in this embodiment, the switching member  22  of the discharging system  20  comprises a blocking member  221  and a conductive member. The conductive member comprises at least two separable conductive elastic members, i.e. conductive elastic pieces  222 . One end of each conductive elastic piece  222  is a fixed end fixed on the discharging circuit board  23  and electrically connected to the discharge element  21 . The other end of each the conductive elastic piece  222  is a free end. The blocking member  221  is arranged between the free ends of at least two conductive elastic pieces  222  to operably separate the conductive elastic pieces  222  from each other, preventing the conductive member being electrical conducting. It should be understood that the function of the blocking member described in one of the embodiments of the present disclosure is to make the switching structure  22  being positioned in the initial open state, where, the discharge circuit is non-conductive, and the blocking member may be operated to be functionally disabled for blocking and the switching member is switched into the intermediate open state. 
     The term “blocking” may be either a physical blocking or an electrical blocking, as long as it may keep the switching member in the initial open state. 
     Specifically, as shown in  FIG. 13 , when the battery pack  50  is in the initial unused state, the blocking member  221  of the discharging system  20  is biasing free ends of the conductive elastic pieces  222  to be separated from each other, preventing the conductive member from being electrical conducting, and the switching member  22  is positioned in the initial open state, while the discharging system  20  is in the first state. 
     As shown in  FIG. 14 , when the battery pack  50  is assembled in the battery dock  88  of the surgical instrument  100 , the protruding portion  842  is inserted into the recess  541  along an extending direction of the recess  541 , and abuts against the blocking member  221 . The blocking member  221  is actuated by the proximal end of the protruding portion  842  and released from the conductive elastic piece  222 . As shown in  FIG. 15 , the conductive elastic pieces  222  are remained to be isolated from each other through the proximal end of the protruding portion  842 , preventing the conductive member to be electrical conductive, where the switching member  22  is remained in the open state, i.e., the intermediate open state, and the discharging system  20  is in the second state. 
     When the surgical instrument  100  completes the surgical operation, the battery pack  50  is removed from the surgical instrument  100 , and the protruding portion  842  is removed from the recess  541  as well as the conductive elastic pieces  222  of the conductive member, where, as shown in  FIG. 16 , the conductive elastic pieces  222  contact with each other so as to be conductive, the switching member  22  is switched to the closed state, and the discharging system  20  comes to the third state, the discharging element  21  and the battery unit  53  are conducting, and the battery unit  53  starts to be discharged. The protruding portion  842  may be arranged on the base assembly  84  or the grip part of the handle assembly. 
       FIG. 17  shows the specific structure of the conductive elastic piece  222  which comprises an elastic body  222   a  having a first end (i.e. a fixed end) connected to the discharging circuit board  23 , and a second end having a bended portion  222   b  which extends toward the other conductive elastic piece  222  arranged on the opposite side thereof, inclining towards the first end in the extending direction, so as to be convenient for locating the blocking member  221 . The blocking member  221  is arranged between the two bended portions  222   b  when the discharging system  20  is in the first state. In addition, the conductive elastic piece  222  also comprises a fitting portion  222   c  disposed on the bended portion  222   b.  The fitting portion  222   c  is arranged such that a line contact formed by the two oppositely disposed bended portions locating the blocking member  221  turns to a face contact, which leads to an increased contact area between the conductive elastic piece  222  and the blocking member  221 , providing more stable location, so as to prevent the blocking member  221  from falling during transportation. 
       FIG. 18  shows the specific structure of the blocking member  221 . The blocking member  221  has a columnar structure and has a slope surface inclined towards a center line of the columnar structure; the blocking member  221  is configured to have this shape, such that when the blocking member  221  is located between two conductive elastic pieces  222 , it is convenient for the amounting of the blocking member  221 ; where, it also facilitates the protruding portion  842  to push the blocking member  221  to be released from arrangement between the two conductive elastic pieces  222 . Since the blocking member  221  is adapted for to isolate the conductive elastic pieces  222 , the blocking member  221  is configured as an insulating member. 
     Embodiment 3 
       FIGS. 20 to 24  show an alternative embodiment of the battery pack  50  and the discharging system  20  of the present disclosure. Alternatively, as shown in  FIG. 21 , on the basis of the abovementioned embodiments, the switching member  22  of the discharging system  20  comprises a blocking member and a conductive member, and the blocking member is specifically configured as a first switch  321 , the conductive member is specifically configured as a second switch  322  and the first switch  321  and the second switch  322  are both arranged on the discharging circuit board  23 . 
     Furthermore, as shown in  FIG. 20 , a protruding portion is arranged on the base assembly  84 , provided with a fin portion  843  which is adapted to operably cooperate with the first switch  321  and/or the second switch  322 . The protruding portion may be arranged on the base assembly  84  or the grip part of the handle assembly. 
     Specifically, as shown in  FIG. 22 , when the battery pack  50  is in the initial unused state, the first switch  321  remains switched off, and the second switch  322  is not conducting, where the switching member  22  is in the initial open state, and the discharging system  20  is in the first state. 
     When the battery pack  50  is assembled in the battery dock  88  of the surgical instrument  100 , the protruding portion and the fin portion  843  are inserted into the recess  541  along an extending direction of the recess  541 . The fin portion  843  interacts with the first switch  321  such that the switch  321  is conducting, while the second switch remains in the turn-off state due to the engagement of the fin portion  843 , i.e., the conductive member remains in a non-conductive state, where the switching member  22  is in the intermediate open state, and the discharging system  20  is in the second state. 
     When the surgical instrument  100  completes the surgical operation, the battery pack  50  is removed from the surgical instrument  100 , and the protruding portion and the fin portion  843  are operated to be removed out of the recess  541  as well, where the second switch  322  is switched to be conductive without the engagement with the fin portion  843 , such that the switching member  22  is switched to the closed state, and the discharging system  20  is switched to the third state, where the discharging element  21  and the battery unit  53  are conducting, and the battery unit  53  starts to be discharged. 
     Preferably, the first switch  321  described in this embodiment is a self-locking switch, allowing the first switch remains in the previous state, i.e., a conducting state, after being disengaged with the fin portion  843 . In addition, the second switch  322  described in this embodiment is preferably an electronic switch, such as a photoelectric switch, which is composed of a light emitting end and a light receiving end. When the discharging system  20  is in the second state, the photoelectric switch remains in a non-conductive state due to the blocking of the fin portion  843 . As the fin portion  843  is removed from the recess  541 , the photoelectric switch is no longer blocked, and a connection may be established between the transmitting end and the receiving end, so that the photoelectric switch is conducting, and the discharging system  20  is switched to the third state, thereby self-discharge function of the battery unit  53  of the battery pack  50  is realized. 
     More specifically, the arrangement of the fin portion  843  may be set according to the positions of the first switch  321  and the second switch  322 . In addition, the first switch  321  and the second switch  322  may also be selected from other suitable switching elements, as long as they may comply with the above functional principles. 
     Embodiment 4 
       FIGS. 25 to 29  show still another embodiment of the battery pack  50  and its discharging system  20  described in the present disclosure. As an alternative embodiment, on the basis of the abovementioned embodiments, the conductive member of the switching member  22  of the discharging system  20  is configured as a normal-close switch  421 , and the blocking member is a stop member. For example, in this embodiment, the stop member is configured as a limit plate  422 , and the limit plate  422  is configured to abut against the normal-close switch  421 , such that the switch  421  is in initial switched-off (open) state, as shown in  FIG. 26 . 
     As further shown in  FIG. 25 , a tip is arranged on a proximal end of the protruding portion  844  of this embodiment, which is adapted to operably break the limit plate  422 , such that the limit plate  422  capable of maintaining the normal-close switch  421  in the switched-off state without blocking. The stop member  422  may be made of a brittle sheet material that is easy to be broken by operation, or the stop member  422  may be provided with indentations to facilitate the breaking by operation thereof. 
     Specifically, as shown in  FIG. 26 , when the battery pack  50  is in the initial unused state, the limit plate  422  abuts against the normal-close switch  421 , forcing it in the switched-off state, where, the switching member  22  is in the initial open state, and the discharging system  20  is in the first state. 
     When the battery pack  50  is assembled in the battery dock  88  of the surgical instrument  100 , the protruding portion  844  and the tip are inserted into the recess  541  along the extending direction of the recess  541 , and the tip is in contact with the stop member  422  and causes it to break. At this time, the normal-close switch  421  is remained in the switched off state due to engagement with the protruding portion  844 , i.e., the conductive member remains in the non-conductive state, where, the switching member  22  is in the intermediate open state, and the discharging system  20  is in the second state. 
     When the surgical instrument  100  completes surgical operation, the battery pack  50  is removed from the surgical instrument  100 , and the protruding portion  844  and the tip are removed from the recess  541  as well, where the normal-close switch  421  is conducting due to being disengaged with the limit plate  422 , and the switching member  22  is switched to the closed state, the discharging system  20  is switched to the third state, where the discharging element  21 , the battery unit  53  are conducting, and the battery unit  53  starts to be discharged. 
     It should be understood that the normal-close switch described in this embodiment refers to a switch in the closed state without external force. When a switch button is toggled or the switch is controlled by an automatic device to toggle, the switch is switched to an open circuit. For example, the normal-close switch may be a travel switch, a pressure relay, etc. 
     More specifically, the arrangement of the tip of the protruding portion  844  may be made according to the shape of the normal-closed switch  421  on its own, and the protruding portion  844  may be arranged on the base assembly  84  or the grip part of the handle assembly. The position of the limit plate  422  may also be set according to the switched off position of the normal-close switch  421 , as long as it may meet the above functional principle. 
     The above embodiments are merely for clear description, and are not intended to limit the detailed description of the embodiments. For a person skilled in the art, other changes or modifications in different forms may be made on the basis of the above description. It is not necessary and impossible to list all the embodiments here. The obvious changes or modifications derived therefrom still fall within the scope of the present disclosure.