Abstract:
A bending control mechanism includes a turning power input mechanism A, a turning transmission mechanism B, a locking mechanism C and a linear power output mechanism D; further, the turning power input mechanism A and the turning transmission mechanism B which are coaxially arranged have a relative rotating angle range in the circumferential direction; the turning power input mechanism A sequentially rotates in an angle I, an angle range II and an angle III while rotating relative to the turning transmission mechanism B from one end angle to the other end angle within a relative rotating angle range, wherein the angle I or the angle III corresponds to turning; the angle range II corresponds to a locking state. With the adoption of the mechanism, the problem of turning and fixing of the surgical instrument in a human body during surgery is solved, and the risk of surgery is reduced.

Description:
CROSS REFERENCE OF RELATED APPLICATION 
       [0001]    This is a U.S. National Stage under 35 U.S.C 371 of the International Application PCT/CN2015/090208, filed Sep. 22, 2015, which claims priority under 35 U.S.C. 119(a-d) to CN 201510026528.0, filed Jan. 19, 2015. 
     
    
     BACKGROUND OF THE PRESENT INVENTION 
     Field of Invention 
       [0002]    The invention relates to a bending control mechanism for surgical stapler, and more particularly to a mechanism for controlling turning and locking the jaw of the endoscopic stapler. 
       Description of Related Arts 
       [0003]    The action principle of surgical stapler is as follows: two corresponding jaws (commonly referred to as anvil assembly and cartridge assembly) are closed to clamp tissue; and then metal suturing nails in cartridge of the stapler are pushed out to perform molding, to sew tissue together. Some staplers are provided with a cutting knife, to cut off the sewn tissue together. 
         [0004]    With the progress of technology, the traditional mode of operation is gradually turned into the endoscopic surgery. In the endoscopic surgery, a number of small incisions with diameter of 5-12 mm are made in different parts of the abdomen or chest; camera lens and a variety of special surgical instruments are inserted in these small incisions; images of various organs in the abdominal cavity taken by the camera inserted in the abdominal cavity are transmitted to the TV screen; by observing the images, the surgeon operates a variety of surgical instruments to complete the operation. 
         [0005]    Wherein, the endoscopic stapler plays the most crucial role in the operation. Due to the limitation of space in the abdominal cavity or thoracic cavity, in some extreme cases, the traditional linear endoscopic stapler is unable to effectively reach the surgical site to perform clamping, transection and anastomosis of tissue; therefore, an elbow stapler with stapler jaw (including anvil assembly and cartridge assembly) capable of turning is required. In a straight line state, this kind of elbow stapler capable of turning enters the thoracic cavity or abdominal cavity through puncture outfit; the jaw is controlled by the bending control mechanism on the in-vitro handle to bend to a certain angle; and a series of operations such as clamping, transection and anastomosis are performed on the surgical site. After the operation is completed, the elbow stapler exits the body after turning to the straight line state. 
         [0006]    Thus, there is an urgent need for a reasonable bending control mechanism, to control the angle required for rotation of the stapler jaw, so that the operation is convenient; at the same time, the angle required for the stapler jaw is firmly locked, to prevent security risks in the unpredictable force. 
       SUMMARY OF THE PRESENT INVENTION 
       [0007]    In view of the defects in the prior art, an object of the present invention is to design a simple control mechanism, to reach the purpose of making the stapler jaw turn by pulling the wrench, and lock the stapler jaw at the selected angle. Thus, in the thoracic cavity or abdominal cavity, even the stapler jaw is subject to unpredictable forces, the jaw will not turn, thereby reducing the potential risks. 
         [0008]    A bending control mechanism according to the present invention comprises: a wrench constituting a turning power input mechanism A and a lifting ring which synchronously rotates with the wrench; a central shaft constituting a turning transmission mechanism B; a cam lock, a compression spring and a rotating head constituting a locking mechanism C, wherein the cam lock is engaged with the turning transmission mechanism B; and a rack constituting a linear power output mechanism D, wherein the rack is engaged with a gear arranged on the central shaft; further: the turning power input mechanism A and the turning transmission mechanism B which are coaxially arranged have a relative rotating angle range in a circumferential direction; the turning power input mechanism A sequentially rotates in an angle I, an angle range II and an angle III while rotating relative to the turning transmission mechanism B from one end angle to the other end angle of the relative rotating angle range; when the turning power input mechanism A is within the angle range II, the cam lock driven by the compression spring is locked at the rotating head in meshing manner to lock the turning transmission mechanism B, so that the turning transmission mechanism B and linear power output mechanism D remain relatively stationary; when the turning power input mechanism A is at the angle I, the cam lock driven by the lifting ring separates from the rotating head to release the turning transmission mechanism B; in addition, the turning transmission mechanism B is able to rotate to a first circumferential direction away from the angle range II accompanied with the turning power input mechanism A, and drive the linear power output mechanism D to displace; when the turning power input mechanism A is at the angle III, the cam lock driven by the lifting ring separates from the rotating head to release the turning transmission mechanism B; in addition, the turning transmission mechanism B is able to rotate to a second circumferential direction away from the angle range II accompanied with the turning power input mechanism A, and drive the linear power output mechanism D to displace; wherein the first circumferential direction is opposite to the second circumferential direction. 
         [0009]    Preferably, an angle range between the angle I and the angle III defines the angle range II. 
         [0010]    Preferably, a plurality of engagement locked positions are arranged at an opening of the rotating head along the circumferential direction; along with rotation of the cam lock, the rotating head is able to be meshed to a corresponding engagement locked position by the cam lock. 
         [0011]    Preferably, a pin hole of the wrench matches with a fan-shaped hole of the central shaft via a pin; an angle of the fan-shaped hole forms the relative rotating angle range; the wrench extends downwards out of a boss; the lifting ring is provided with a wrench fitting groove; and the boss is engaged in the wrench fitting groove. 
         [0012]    Preferably, when the pin is located at one end of the fan-shaped hole, the wrench is at the angle I; when the pin is located at the other end of the fan-shaped hole, the wrench is at the angle III; when the pin is located between one end and the other end of the fan-shaped hole, the wrench is within the angle range II. 
         [0013]    Preferably, the lifting ring is provided with a drive ramp; the cam lock is provided with a driven ramp, and the driven ramp matches with the drive ramp; when the lifting ring driven by the wrench rotates within the angle range II, there is a relative rotation between the lifting ring and the cam lock; when the lifting ring driven by the wrench rotates to the angle I and the angle III, the driven ramp is driven by the drive ramp, so that the cam lock is away from the rotating head, to separate from an engagement locking with the rotating head. 
         [0014]    Preferably, the wrench is provided with a cover plate; the cam lock is provided with a compression spring support surface; a compression spring is connected between the cover plate and the compression spring support surface. 
         [0015]    Preferably, a limit boss is arranged at the opening of the rotating head; and an angle limiting groove matching with the limit boss is arranged on the wrench. 
         [0016]    A surgical instrument with bending control mechanism according to the present invention comprises the above-mentioned bending control mechanism. 
         [0017]    Preferably, the surgical instrument is a surgical stapler; the linear power output mechanism D of the bending control mechanism is connected to the jaw of the stapler. 
         [0018]    Compared with the prior art, the present invention has the following beneficial effects: 
         [0019]    1. By the present invention, one or more locations are able to be locked in the operation, so as to bend and fix the stapler jaw to the required position, to complete the operation. 
         [0020]    2. The present invention is provided with simple mechanism and fewer parts; most of the parts are made by injection molding process, so they are simple to manufacture and with low cost. 
         [0021]    3. The bending control mechanism according to the present invention is able to be widely applied to other mechanical operating parts; it is easy to control and switch over. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0022]    Other features, objects, and advantages of the present invention will become more apparent from reading the description of non-limiting embodiments detailed with reference to the following figures: 
           [0023]      FIG. 1  is a main appearance diagram of a surgical stapler comprising bending control mechanism; 
           [0024]      FIG. 2  is a main appearance diagram of the bending control mechanism; 
           [0025]      FIG. 3  is a detailed view of a split structure of the bending control mechanism; 
           [0026]      FIG. 4  is a top view of a rotating head part of the bending control mechanism. 
       
    
    
       [0027]    In the drawings:
     1 -wrench;     102 -pin hole;     104 -cover plate;     105 -boss;     3 -central shaft;     301 -gear;     303 -fan-shaped hole;     304 -connecting groove;     5 -rack;     501 -rack structure;     6 -pin;     7 -upper part of rotating head;     701 -opening;     702 -locating tooth space;     8 -lifting ring;     801 -wrench fitting groove;     802 -drive ramp;     9 -cam lock;     901 -connection boss;     902 -locating tooth;     903 -compression spring support surface;     904 -driven ramp;     10 -compression spring.   
 
       DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0051]    The invention is described in detail as follows with reference to specific embodiments. The following embodiments will help provide further understanding of the invention for those skilled in the art, and not in any way limit the invention. It shall be noted that several variants and improvements is able to be made without departing from concept of the invention for ordinary persons skilled in the art. All these fall within the protection scope of the invention. 
         [0052]    The present invention provides a surgical instrument with a bending control mechanism, comprising the bending control mechanism. The surgical instrument is a surgical stapler; a linear power output mechanism D of the bending control mechanism is connected to a jaw of the stapler. 
         [0053]    As shown in  FIG. 1 , the present invention provides an endoscopic surgical stapler with the bending control mechanism. The endoscopic surgical stapler comprises a tubular structure; the tubular structure is provided with a stapler jaw at a remote end, and a near end is connected to the bending control mechanism. 
         [0054]      FIG. 2  shows the bending control mechanism in the present invention; the bending control mechanism comprises a wrench  1  and an upper part of rotating head  7 , wherein the wrench  1  is installed on the upper part of rotating head  7 . 
         [0055]    Specifically, the bending control mechanism comprises a wrench constituting a turning power input mechanism A and a lifting ring which synchronously rotates with the wrench; a central shaft  3  constituting a turning transmission mechanism B; a cam lock  9 , a compression spring  10  and an upper part of rotating head  7  constituting a locking mechanism C, wherein the cam lock  9  is engaged with the turning transmission mechanism B; and a rack  5  constituting a linear power output mechanism D, wherein the rack  5  is engaged with a gear  301  arranged on the central shaft  3 ; further: the turning power input mechanism A and the turning transmission mechanism B which are coaxially arranged have a relative rotating angle range in a circumferential direction; the turning power input mechanism A sequentially rotates in an angle I, an angle range II and an angle III while rotating relative to the turning transmission mechanism B from one end angle to the other end angle of the relative rotating angle range; when the turning power input mechanism A is within the angle range II, the cam lock  9  driven by the compression spring  10  is locked at the rotating head in meshing manner to lock the turning transmission mechanism B, so that the turning transmission mechanism B and linear power output mechanism D remain relatively stationary; when the turning power input mechanism A is at the angle I, the cam lock  9  driven by the lifting ring  8  separates from the rotating head to release the turning transmission mechanism B; in addition, the turning transmission mechanism B is able to rotate to a first circumferential direction away from the angle range II accompanied with the turning power input mechanism A, and drive the linear power output mechanism D to displace; when the turning power input mechanism A is at the angle III, the cam lock  9  driven by the lifting ring  8  separates from the rotating head to release the turning transmission mechanism B; in addition, the turning transmission mechanism B is able to rotate to a second circumferential direction away from the angle range II accompanied with the turning power input mechanism A, and drive the linear power output mechanism D to displace; wherein the first circumferential direction is opposite to the second circumferential direction. 
         [0056]      FIG. 3  shows a bending control mechanism provided by the first embodiment of the present invention, comprising a wrench  1 , a central shaft  3 , a lifting ring  8 , a cam lock  9 , an upper part of rotating head  7  and a compression spring  10 ; wherein an opening  701  provided with a series of locating grooves  702  is arranged on the upper part of rotating head  7 ; the central shaft  3  is provided with a gear  301 , which is connected with a stapler jaw by connecting with the rack  5  and further through a connecting device placed in the tubular structure; a lifting ring  8  in coaxial arrangement with the central shaft  3  has a drive ramp  802 ; a cam lock  9  in coaxial arrangement with the central shaft  3  comprises a connecting boss  901  connected with the central shaft  3 , a driven ramp  904  matches with the drive ramp  802  of the lifting ring  8 , and a locating tooth  902 ; the wrench  1  matches with the lifting ring  8  via a boss  105 , and connected with the central shaft  3  via a pin  6 ; a compression spring  10  is arranged between the wrench  1  and the lifting ring  8 . 
         [0057]    Preferably, an angle range between the angle I and the angle III defines the angle range II. 
         [0058]    Preferably, a plurality of engagement locked positions are arranged at the opening of the rotating head along the circumferential direction; along with rotation of the cam lock  9 , the rotating head is able to be meshed to a corresponding engagement locked position by the cam lock  9 . 
         [0059]    More specifically, the surgical instrument is a surgical stapler; the linear power output mechanism D of the bending control mechanism is connected to the jaw of the stapler. Wherein, the locating groove  702  on the rotating head has a middle position, so that the stapler jaw is in a straight line state. 
         [0060]    Preferably, a pin hole  102  of the wrench  1  matches with a fan-shaped hole  303  of the central shaft  3  via the pin  6 ; an angle of the fan-shaped hole  303  forms the relative rotating angle range; the wrench  1  extends downwards out of the boss  105 ; the lifting ring  8  is provided with a wrench fitting groove  801 ; and the boss  105  is engaged in the wrench fitting groove  801 . 
         [0061]    Preferably, when the pin  6  is located at one end of the fan-shaped hole  303 , the wrench  1  is at the angle I; when the pin  6  is located at the other end of the fan-shaped hole  303 , the wrench  1  is at the angle III; when the pin  6  is located between one end and the other end of the fan-shaped hole  303 , the wrench  1  is within the angle range II. 
         [0062]    Preferably, the lifting ring  8  is provided with a drive ramp  802 ; the cam lock  9  is provided with a driven ramp  904 , and the driven ramp  904  matches with the drive ramp  802 ; when the lifting ring  8  driven by the wrench  1  rotates within the angle range II, there is a relative rotation between the lifting ring  8  and the cam lock  9 ; when the lifting ring  8  driven by the wrench  1  rotates to the angle I and the angle III, the driven ramp  904  is driven by the drive ramp  802 , so that the cam lock  9  is away from the rotating head, to separate from an engagement locking with the rotating head. 
         [0063]    Preferably, the wrench  1  is provided with a cover plate  104 ; the cam lock  9  is provided with a compression spring support surface  903 ; a compression spring  10  is connected between the cover plate  104  and the compression spring support surface  903 . 
         [0064]    Preferably, a limit boss is arranged at the opening of the rotating head; and an angle limiting groove matching with the limit boss is arranged on the wrench  1 . 
         [0065]    As shown in  FIG. 4 , the locating grooves  702  on the rotating head are circumferentially arrayed; a angle distribution of each locating groove  702  is not equidistant. In addition, a limit boss is arranged at the opening of the rotating head, to ensure that the wrench rotates in a certain angle, to prevent over-rotation. 
         [0066]    As a variant embodiment of the first embodiment provided by the present invention, the angle distribution of the above-mentioned locking grooves is also able to be equal. 
         [0067]    More specifically, the present invention is a bending control mechanism of endoscopic stapler, comprising a wrench  1 , a compression spring  10 , a cam lock  9 , a lifting ring  8 , a central shaft  3 , an upper part of rotating head  7 , a rack  5  and a pin  6 . Wherein, the upper part of rotating head  7  has an opening, which is adapted for accommodating the wrench  1 , the compression spring  10 , the cam lock  9 , the lifting ring  8  and the central shaft  3 ; the above-mentioned wrench  1 , compression spring  10 , cam lock  9 , lifting ring  8  and central shaft  3  and the opening of the rotating head are arranged coaxially; a series of locating grooves  702  are arranged in the opening. The central shaft  3 , the lifting ring  8  and the cam lock  9  are arranged from inside to outside; a connecting boss  901  of the cam lock  9  matches with a connecting groove  304  of the central shaft  3 ; a driven ramp  904  matches with a drive ramp  802  of the lifting ring  8 ; a locating tooth  902  is arranged in a series of locating grooves  702  on the rotating head. A boss  105  of the wrench  1  matches with a wrench fitting groove  801  of the lifting ring  8 . The compression spring  10  is placed between a compression spring support surface  903  of the cam lock  9  and a cover plate  104  of the wrench  1 . A pin hole  102  of the wrench  1  matches with a fan-shaped hole  303  of the central shaft  3  via the pin  6 . The rack  5  is arranged in the upper part of rotating head  7 , and engaged with a gear  301  of the central shaft  3 . 
         [0068]    When the wrench is rotated, the boss  105  of the wrench  1  drives the lifting ring  8  to rotate for an angle; the lifting ring  8  drives the driven ramp  904  of the cam lock  9  through the drive ramp  802 , so that the cam lock  9  rises, and the locating tooth  902  and the locating groove  702  of the upper part of rotating head  7  disengage from an engaging state; when the wrench is rotated continuously, the pin  6  drives the central shaft  3  to rotate through the fan-shaped hole  303 , and the central shaft  3  drives the cam lock  9  to rotate and drives the rack  5  to move forward and backward, to play a role of turning. 
         [0069]    When the wrench  1  rotates to a next position, the wrench  1  will be released; the compression spring  10  will push the cam lock  9 , to clamp the locating tooth  902  into another locating groove  702  of the upper part of rotating head  7 . At this time, the cam lock  9  is able to lock the central shaft  3 , for avoiding rotating freely. Since the locating tooth  902  of the cam lock  9  is engaged with a straight line segment of the locking groove  702  of the upper part of rotating head  7 , a rotation of the gear  301  driven by the rack  5  is unable to rotate the cam lock  9  to achieve a purpose of locking. 
         [0070]    A limit boss is arranged at the opening of the upper part of rotating head, to limit the rotation angle of the wrench and avoid excessive rotation. 
         [0071]    Specific embodiments of the invention are described above. It shall be understood that the invention is not limited to the above-mentioned specific embodiments, and those skilled in the art is able to make different variants and modifications within the scope of the claims, and it shall not affect the substance of the invention.