Patent Publication Number: US-2017360277-A1

Title: Medical power supply system

Description:
This application is a continuation based on PCT/JP2015/055876, filed on Feb. 27, 2015. The content of the United States Patent Application is incorporated herein by reference. 
    
    
     TECHNICAL FIELD 
     The present invention relates to a medical power supply system. 
     BACKGROUND ART 
     In the related art, it is known that various treatments are performed on a patient while minimizing stress using a trocar and a medical instrument. 
     The inner needle punctures a body wall of a patient and a trocar is inserted into an abdominal cavity in the state where the trocar is integrally combined with the inner needle having a sharp puncturing portion at the tip. After the trocar is inserted into the abdominal cavity, the inner needle is removed such that the trocar is placed in the body wall and the trocar is then used as a guide tube for a treatment tool that performs a treatment in the abdominal cavity. 
     As a medical instrument, the treatment tool is inserted into the body of a patient via the trocar. In the case where the treatment tool uses electricity to perform treatments, a cable for supplying power is usually connected to the treatment tool. This cable reduces the manipulability of the medical instrument when an operator performs treatments. 
     In this regard, a technology in which wireless power supply is performed between a trocar and a medical instrument to eliminate the necessity of a cable is disclosed in Japanese Patent Granted Publication No. 4145395. 
     In the technology described in Patent Literature 1, a primary coil (a power transmitting coil) provided at a trocar and a secondary coil (a power receiving coil) provided at a treatment tool which has been inserted into the trocar are electromagnetically coupled, thereby, it is possible to perform wireless power supply from the trocar to the treatment tool. 
     SUMMARY OF INVENTION 
     A medical power supply system according to a first aspect of the present invention includes a medical instrument which has an elongated insertion portion that is inserted into a body, an end effector that is provided at a distal end portion of the insertion portion, and a power receiver that has a power receiving member and receives power to be supplied to the end effector; and a guide tube which has a power transmitting member that is connected to a power source and that is provided at a proximal end side of the guide tube, and which guides the insertion portion of the medical instrument so as to be inserted from the proximal end side into the body. The power receiving member is arranged radially outside the insertion portion, and when the insertion portion is inserted into the guide tube to a predetermined length such that the power transmitting member and the power receiving member are close to each other, a power transmitting side proximal end surface of the power transmitting member and a power receiving side distal end surface of the power receiving member face each other in an axial direction of the insertion portion and are in a positional relationship such that wireless power supply is possible. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a side view illustrating a treatment tool that is a medical instrument of a medical power supply system according to a first embodiment of the present invention. 
         FIG. 2  is a front view of the treatment tool shown in  FIG. 1 . 
         FIG. 3  is a side view illustrating a trocar that is a guide tube of the medical power supply system according to the first embodiment of the present invention. 
         FIG. 4  is a plan view of the trocar shown in  FIG. 3 . 
         FIG. 5  is a view illustrating a procedure when the medical power supply system according to the first embodiment of the present invention is used. 
         FIG. 6  is a view illustrating a procedure when the medical power supply system according to the first embodiment of the present invention is used. 
         FIG. 7  is a schematic diagram illustrating the relationship between the sizes of a power receiving member and a power transmitting member of the medical power supply system according to the first embodiment of the present invention. 
         FIG. 8  is a perspective view illustrating a modified example of the medical power supply system according to the first embodiment of the present invention. 
         FIG. 9  is a side view illustrating the modified example of the medical power supply system according to the first embodiment of the present invention. 
         FIG. 10  is a side view illustrating a treatment tool that is a medical instrument of a medical power supply system according to a second embodiment of the present invention. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     First Embodiment 
     Hereinafter, a first embodiment of the present invention is described with reference to  FIGS. 1 to 4 . A medical power supply system of the present embodiment includes a trocar (a guide tube) that is placed into a patient or the like and a medical instrument that is inserted and used in the trocar. 
       FIG. 1  is a side view illustrating a treatment tool  10  that is a medical instrument of the present embodiment.  FIG. 2  is a front view of the treatment tool  10 . 
     The treatment tool  10  includes an insertion portion  20 , a treatment portion (an end effector)  30 , a manipulation portion  40 , and a power receiver  50 . The insertion portion  20  is formed of metal, resin, or the like in the shape of an elongated tube and at least a part of the insertion portion  20  is inserted together with the treatment portion  30  into a body. 
     In the description of the present specification, one end of the treatment tool  10  at which the manipulation portion  40  is provided and one end of a trocar  70  shown in  FIG. 3  from which the insertion portion  20  of the treatment tool  10  is inserted into a body are each referred to as a “proximal end”. 
     The treatment portion  30  is provided at a distal end portion of the insertion portion  20 . The treatment portion  30  of the present embodiment is an openable and closable forceps and a basic structure thereof is publically known. As a high frequency current is supplied to the treatment portion  30  with tissue being grasped by the treatment portion  30 , it is possible to perform tissue ablation, coagulation, hemostasis, or the like. A power transfer member  60  for driving and opening-closing the treatment portion  30  is formed of a conductive material such as metal in the shape of a rod or a wire. The distal end portion of the power transfer member  60  is connected to the treatment portion  30 . The power transfer member  60  extends to the manipulation portion  40  through the insertion portion  20 . 
     The manipulation portion  40  includes a main body  41  to which the insertion portion is connected, a handle  42  that is to be grasped by a manipulator, and a trigger  43  and a power-on button  44  that are manipulated by the manipulator. 
     The power transfer member  60 , which extends to an inside of the insertion portion  20  and the main body  41 , is connected to the trigger  43 . When the manipulator manipulates the trigger  43 , the power transfer member  60  moves advanced or retracted to open or close the treatment portion  30 . 
     The power receiver  50  includes a plate-shaped portion  51  and a planar coil  52 . As shown in  FIG. 2 , the shape of the plate-shaped portion  51  is disk-shaped having a through-hole  51   a  at the center. The plate-shaped portion  51  is formed of an insulating material such as resin. The insertion portion  20  is inserted and fixed into the through-hole  51   a.    
     The planar coil  52  is formed as a metal wire is spirally wound in a single surface. In the present embodiment, the planar coil  52  is formed as a metal wire is spirally wound around the through-hole  51   a  to form a surface with the through-hole  51   a  being centered thereon as shown in  FIG. 2 . The planar coil  52  is arranged in the plate-shaped portion  51  at a middle portion in the thickness direction thereof such that the planar coil  52  is not exposed from the outer surface of the plate-shaped portion  51 . The plate-shaped portion  51  of the present embodiment is formed of transparent resin and therefore the planar coil  52  is visible as shown in  FIGS. 1 and 2 . 
     The power receiver  50  is electrically connected to the main body  41  via a cable  53 . A first end portion of the cable  53  is electrically connected to the planar coil  52  and a second end portion thereof is electrically connected to a power connection member (not shown) in the main body  41  of the manipulator  40 . The power connection member is electrically connected to the power-on button  44  and the power transfer member  60 . 
       FIG. 3  is a side view illustrating the trocar  70 .  FIG. 4  is a plan view of the trocar  70 . The trocar  70  includes a main body portion  71  and a power transmitter  72 . 
     A basic structure of the main body portion  71  is the same as that of a publically known trocar. That is, the main body portion  71  is formed in a tubular shape such that a through-hole (not shown) into which the insertion portion  20  of the treatment tool  10  is insertable extends from a proximal end portion to a distal end portion of the main body portion  71 . The main body portion  71  may have an inner needle or the like for opening a hole in an abdominal wall or a valve for keeping the abdomen being insufflated as needed. 
     The power transmitter  72  is provided at the proximal end side of the main body portion  71 . The power transmitter  72  has a planar coil (i.e., a power transmitting member)  75  and a power transmission cable  76  that is electrically connected to the planar coil  75 . The material and shape of the power transmitter  72  and the arrangement of the planar coil  75  are substantially the same as those of the plate-shaped portion  51  and the planar coil  52  of the power receiver  50 . The planar coil  75  of the power transmitter  72  is arranged so as to be substantially parallel to a proximal end surface of the trocar  70 , that is, a proximal end surface  72   a  of the power transmitter  72  (which can also be referred to as a power transmitting side proximal end surface), and is coated with an insulating material. The power transmitter  72  has a through-hole  72   b  at a central portion thereof. The through-hole  72   b  communicates with the through-hole of the main body portion  71  and the insertion portion  20  of the treatment tool  10  is inserted into the through-hole  72   b . The power transmission cable  76  is electrically connected to a power supply source that is not shown. 
     In the present embodiment, the planar coil  52  of the treatment tool  10  and the planar coil  75  of the trocar  70  are substantially the same in size as shown in  FIGS. 5 and 6 . 
     The planar coil  75  is visible since the power transmitter  72  of the present embodiment is also formed of a transparent material. However, the power receiving member and the power transmitting member may not necessarily be arranged such that they are visible and the plate-shaped portion or the power transmitter may be formed of a colored insulating material. 
     The movement of the medical power supply system of the present embodiment including the treatment tool  10  and the trocar  70  configured as described above operates when being in use is described below. 
     First, the manipulator cuts the abdominal wall of a patient or the like to form an opening into the abdominal cavity. The main body portion  71  of the trocar  70  is inserted from the distal end side thereof into the opening and the trocar  70  is placed in the abdominal wall. The power transmission cable  76  is then connected to the power supply source. The power transmission cable  76  and the power supply source may be connected either before or after the trocar  70  is placed. 
       FIGS. 5 and 6  are views illustrating a procedure when the medical power supply system is used. The manipulator grasps the handle  42  of the treatment tool  10  and inserts the treatment portion  30 , from the proximal end side of the trocar  70 , into the trocar  70  as shown in  FIG. 5 . The treatment portion  30  is first introduced into the main body portion  71  through the though-hole  72   b  of the power transmitter  72  and the insertion portion  20  is then introduced into the main body portion  71 . 
     When the manipulator inserts the treatment tool  10  into the trocar  70  to some extent, the power transmitter  72  of the trocar  70  and the power receiver  50  are close to each other. Thus, the planar coil  75  arranged in the power transmitter  72  and the planar coil  55  arranged in the power receiver  50  face each other in the longitudinal direction of the insertion portion  20  and in radially outside the insertion portion  20 . As the treatment tool  10  is further inserted (to a predetermined length), the treatment portion  30  and the insertion portion  20  are moved relative the trocar  70  toward the distal end side of the main body portion  71 . 
     When the proximal end surface  72   a  (the power transmitting side proximal end surface) of the power transmitter  72  and the distal end surface  51   b  (the power receiving side distal end surface) of the power receiver  50  are close to each other or in contact with each other as shown in  FIG. 6 , the planar coil  75  of the power transmitter  72  and the planar coil  55  of the power receiver  50  are in a positional relationship such that electromagnetic coupling is possible therebetween. In this state, the manipulator can perform various treatments using the treatment tool  10 . 
     When the manipulator desires to supply power to the treatment portion  30 , the manipulator presses the power-on button  44  of the manipulation portion. Power supplied from the power source is then transmitted to the planar coil  75  via the power transmission cable  76 . Power is transmitted from the power transmitter  72  to the power receiver  50 , and thus received by the power receiver  50 , by wireless power supply implemented as electromagnetic coupling occurs between the facing surfaces of the planar coils  75  and  52  which are arranged facing each other in the longitudinal direction of the insertion portion  20 . Thereafter, power is supplied to the treatment portion  30  via the cable  43  and the power transfer member  60 . 
     As described above, the medical power supply system according to the present embodiment is configured such that the power transmitter  72  provided in the trocar  70  and the power receiver  50  provided in the treatment tool  10  are electromagnetically coupled, outside the trocar  70  and radially outside the insertion portion  20 , to perform wireless power supply. In the medical power supply system according to the present embodiment, the diameter size of an insertion portion of a medical instrument, which is inserted into the trocar  70 , does not affect the transmission efficiency of wireless power supply. Therefore, even when medical instruments having insertion portions with different diameter sizes are used, it is possible to provide the same wireless power supply properties for all medical instruments. Accordingly, it is possible to uniformize the wireless power supply properties for all medical instruments while significantly improving the degree of freedom of design of medical instruments. 
     When at least a part of the insertion portion  20  of the treatment tool  10  is made of a magnetic member as a modified example of the above embodiment, it is possible to induce a magnetic flux between the planar coils  52  and  75  of the power receiver  50  and the power transmitter  72  along the longitudinal axis of the insertion portion  20  during wireless power supply, thereby increasing the transmission efficiency. For example, the insertion portion  20  may be made of stainless steel (SUS420). It is also possible to give magnetic properties to the insertion portion  20  by coating an outer surface of the insertion portion  20  only in a specific area thereof extending in the axial direction with a magnetic member (for example, nickel or the like). The insertion portion  20  may also be configured by arranging a soft magnetic member such as ferrite on the inner surface of a cylindrical member formed of a nonconductive material such as resin. 
     Instead of the insertion portion  20 , even when the power transfer member  60  is configured to include a magnetic member, it is possible to induce a magnetic flux between the planar coils  52  and  75  of the power receiver  50  and the power transmitter  72  in the longitudinal direction of the insertion portion  20  to improve the transmission efficiency, similar to the modified example described above. For example, similar to the insertion portion  20  described above, the power transfer member  60  may be coated with nickel on a surface thereof or may be made of stainless steel (SUS420). A wire-shaped member utilizing a soft magnetic member such as iron, silicon steel, soft ferrite, or Permalloy may also be used as the power transfer member  60 . 
     Both of the power transfer member  60  and the insertion portion  20  of the treatment tool  10  may be magnetic. 
     In addition, as shown in  FIG. 7 , a diameter size  52   r  of the planar coil  52  of the treatment tool  10  may be set to be greater than a diameter size  75   r  of the planar coil  75  of the trocar  70 . That is, the area of a power receiving region (the power receiving area) of the planar coil  52  of the power receiver  50  may be set to be greater than the area of a power transmitting region (the power transmitting area) of the planar coil  75  of the power transmitter  72 . This configuration can increase the transmission efficiency by increasing the magnetic flux that can be received by the power receiver  50  in the magnetic flux generated by the power transmitter  72 . 
     In the present embodiment, the power receiver  50  and the power transmitter  72  are disc-shaped and the power receiving member and the power transmitting member are exemplified by the planar coils  52  and  75  that are formed as metal wires are spirally wound around the through-holes  51   a  and  72   b  into which the insertion portion  20  is inserted. However, the present embodiment is not limited to this example. For example, a plurality of planar coils may be provided around the though-hole  72   b.    
     MODIFIED EXAMPLE 
     Although the power receiving member and the power transmitting member are made of the planar coils  52  and  75  in the first embodiment, any power receiving and transmitting members may be employed as long as wireless power supply is possible. For example, the power receiving member and the power transmitting member may be made of planar electrodes formed of metallic foil or the like, instead of planar coils. 
       FIG. 8  is a perspective view illustrating a power transmitter  721  in the modified example.  FIG. 9  is a side view of the power transmitter  721 . The power transmitter  721  of this modified example has a planar electrode  751 . The planar electrode  751  is at least electrically divided into two regions  751   a  and  751   b . For example, the planar electrode  751  is divided into concentric circular rings around the through-hole  72   b . The planar electrode  751  is divided such that the areas of the electrodes  751   a  and  751   b  are substantially equal. The planar electrode  751  is arranged over an area, which extends from the opening edge of the through-hole  72   b , into which the insertion portion  20  of the treatment tool  10  is inserted, to near the outer periphery of the power transmitter  721 , in a surface  721   a  of the power transmitter  721  at the proximal end side thereof and is coated with an insulating material such that the surface of the planar electrode  751  is not exposed from the outer surface. The planar electrode  751  is arranged closer to the proximal end surface of the power transmitter than when a planar coil is used. A planar electrode is also arranged in the power receiver (not shown). The material, shape, and arrangement of the planar electrode of the power receiver are substantially the same as those of the power transmitter  721 . 
     Wireless power is supplied to planar electrodes arranged in the power receiving and transmitting portions to face each other with an insulating material provided therebetween. In this case, the planar electrodes facing each other are connected through electric field coupling. Specifically, two pairs of planar electrodes facing each other are formed between the power receiving and transmitting portions and wireless power supply from the power transmitter to the power receiver can be performed through electric field coupling between the planar electrodes facing each other. In addition, the planar electrode of each of the power transmitting and receiving portions is divided into concentric circular rings around the through-hole. Therefore, even when the power receiver moves (rotates) about the axial direction of the insertion portion relative to the power transmitter as the treatment tool is manipulated, the facing areas of the electrodes do not change, thereby enabling reliable power transmission. 
     In this modified example, even when medical instruments having insertion portions with different diameter sizes are used, it is possible to provide the same wireless power supply properties for all medical instruments, similar to the first embodiment. In addition, when planar electrodes are used as the power transmitting and receiving members as in this modified example, it is possible to reduce the thicknesses of the power receiving and transmitting portions. 
     Second Embodiment 
     A medical power supply system  101  according to a second embodiment will now be described with reference to  FIG. 10 . In the embodiment described below, elements which have functions or structures similar to the elements of the medical power supply system according to the first embodiment described above are denoted by the same reference numbers as those of the first embodiment and descriptions similar to the first embodiment are omitted. 
       FIG. 10  is a side view illustrating a medical instrument  10  and a trocar  70  in a medical power supply system  101 . The medical power supply system  101  according to the present embodiment differs from the first embodiment in the power receiver and the power transmitter. 
     Instead of the plate-shaped portion  51  of the first embodiment, a cylindrical portion  511  extending in the axial direction of the insertion portion  20  is provided at a distal end side of a main body  41  of a treatment tool  10 . A power receiver  502  includes a power receiving coil  522  wound along the axial direction in the cylindrical portion  511  as shown in  FIG. 10 . The power receiving coil  522  is arranged along the axial direction of the through-hole  512   a  and the surface of the power receiving coil  522  is coated such that the power receiving coil  522  is not exposed from the inner circumferential surface of the through-hole  512   a.    
     As shown in  FIG. 10 , a power transmitter  722  includes a cylindrical portion  722   a  extending in the axial direction and a power transmitting coil  752  as a power transmitting member which is wound along the axial direction around the axial line of an insertion hole  722   b  of a trocar  701  in the cylindrical portion  722   a.    
     When the medical power supply system  101  according to the present embodiment is used, the treatment tool  10  is inserted into the trocar  701 . As the treatment portion  30  of the treatment tool  10  protrudes from the trocar  701 , a proximal end surface  722   c  of the power transmitter  722  (a proximal end surface at the power transmitting side) and a distal end surface  512   b  of the power receiver  501  (a distal end surface at the power receiving side) approach and face each other, allowing the power transmitting coil  752  and the power receiving coil  522  to be in a positional relationship such that electromagnetic coupling is possible therebetween. When the manipulator presses the power-on button  44  of the manipulation portion with the proximal end surface  722   c  of the power transmitter  722  and the distal end surface  512   b  of the power receiver  501  being close to each other or in contact with each other, wireless power supply is performed between the power transmitting coil  752  and the power receiving coil  522 . 
     Similar to the first embodiment, the medical power supply system  101  according to the present embodiment is configured such that wireless power supply is performed by producing electromagnetic coupling, outside the trocar  701  and radially outside the insertion portion  20 . Therefore, even when medical instruments having insertion portions with different diameter sizes are used, it is possible to provide the same wireless power supply properties for all medical instruments. 
     When at least a part of the insertion portion  20  of the treatment tool  10  is made of a magnetic member in the present embodiment, it is possible to induce a magnetic flux of the power transmitting coil  752  in the longitudinal direction of the insertion portion  20  when wireless power supply is performed, thereby increasing the transmission efficiency. When the power transfer member  60  is configured to include a magnetic member, it is also possible to increase the transmission efficiency as described above. 
     Although the medical instrument is exemplified by a treatment tool in each of the above embodiments, the end effector of the present invention is not limited to the forceps described above and any end effector may be used as long as it can provide a specific function when power is supplied thereto. For example, the medical instrument may be a high frequency knife that is used when current is applied thereto or an observation means that includes an image capturing element, an optical system, a lighting mechanism, or the like. 
     Although the guide tube of the present invention is exemplified by a trocar in each of the above embodiments, the guide tube of the present invention is not limited to the trocar described above. Thus, the present invention may be applied to an overtube which is used to introduce an endoscope or a treatment tool into a body cavity, or the like, as the guide tube. 
     Although the embodiments of the present invention have been described above, the technical scope of the present invention is not limited to the above embodiments, and the combinations of elements in each of the embodiments may be changed, various modifications may be made to each of the elements, and any of the elements may be removed without departing from the spirit of the present invention.