Abstract:
A connecting mechanism for an electronic endoscope system is provided. The connecting mechanism is for detachably connecting a scope and a processor unit of the electronic endoscope system. The connecting mechanism includes a rotational cylinder, a linear movable member, and a sensor. The rotational cylinder locks the scope-side connector section to the processor-side connector section by rotating the rotational cylinder, when the scope-side connector section is docked with the processor-side connector section. The linear movable member is moved linearly along a tangent of the rotational cylinder in cooperation with the rotation of the rotational cylinder. The sensor detects whether the linear movable member has arrived at a predetermined position. The predetermined position corresponds to a locking position where the scope-side connector section and the processor-side connector section are locked together by the rotational cylinder.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to a connector for detachably connecting an endoscope to a processor unit. 
         [0003]    2. Description of the Related Art 
         [0004]    In an electronic endoscope system, the processor unit, which is used to process image signals from a scope, is generally set up for use as a separate unit, and the scope is set up for use as a device that can be detachably attached to the processor unit. When connecting the scope to the processor unit, the cylindrical connector of the scope is docked with the cylindrical connector of the processor unit, and a lock lever provided on the cylindrical connector of the processor unit is rotated so that the cylindrical connector of the scope securely locks into the cylindrical connector of the processor by means of a bayonet mount mechanism. 
         [0005]    Since communication between the processor unit and the scope should only be started after establishing a secured mechanical connection between the connectors, determination of whether or not the connectors are securely docked together is required. Conventionally, this determination is achieved by the signal from a limit switch that is engaged by a protuberance provided on the periphery of the connector provided on the processor unit, and such that the limit switch is operated by the rotation of the cylindrical connector of the processor unit. 
       SUMMARY OF THE INVENTION 
       [0006]    In the conventional connection structure above, the engagement of the limit switch is effected directly by the arced movement of the connector, which means that the position of the limit switch must be accurately set during assembly of the device. Particularly, a cylindrical connector, subjected to rotational operation, requires a large tolerance and is subjected to play of movement. This results in the connector not being stable enough to enable easy accurate positioning of the limit switch. 
         [0007]    Consequently, an object of the present invention is to provide a connecting mechanism for an electronic endoscope that does not require fine position adjustment when installing the sensor whilst still reliably detecting whether or not the connector is locked. 
         [0008]    According to the present invention, a connecting mechanism for an electronic endoscope system is provided. The connecting mechanism is for detachably connecting a scope to the processor unit of an electronic endoscope system. The connecting mechanism includes a rotational cylinder, a linear movable member, and a sensor. The rotational cylinder locks the scope-side connector section (the connector provided on the scope) to the processor-side connector section (the connector provided on the processor) by turning the rotational cylinder when the scope-side connector section is fully inserted into the processor-side connector section. The linear movable member is displaced linearly along a tangent of, and in co-operation with, the movement of the rotational cylinder. The sensor detects whether the linear movable member has arrived at a predetermined position, which corresponds to the locking position where the scope-side connector section and the processor-side connector section are locked together by the rotational cylinder. 
     
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]    The objects and advantages of the present invention will be better understood from the following description, with reference to the accompanying drawings in which: 
           [0010]      FIG. 1  is a front view of the processor-side connector that is provided on the processor unit; 
           [0011]      FIG. 2  is a side cross-sectional view of the processor-side connector; and 
           [0012]      FIG. 3  is a plan view only illustrating the relationship between the casing, the sliding plate, and the sensor. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0013]    The present invention is described below with reference to the embodiments shown in the drawings. 
         [0014]      FIG. 1  is the front view of a connector (the processor-side connector)  10  that is provided on the surface of the processor unit of the present embodiment. Further,  FIG. 2  is a side cross-sectional view of the connector  10 . In  FIG. 2 , members which do not actually exist in this section are also depicted. 
         [0015]    At the center of the processor-side connector  10 , there is provided a cylindrical socket  11  (only shown in  FIG. 1 ), where a plurality of terminals (not shown) that are provided on the scope-side connector are plugged into. Namely, a plurality of pinholes are formed in the end face of the socket  11  and each of the terminals is inserted into the pinholes. Around the socket  11 , a cylindrical retainer  12  is coaxially located. The front end of the cylindrical retainer  12  is provided with a flange  12   a  that extends radially outside. The base end of the cylindrical retainer  12  penetrates the casing  16  of the processor unit and the cylindrical retainer  12  is fixed to the casing  16  via a support member (not shown). 
         [0016]    A first rotational cylinder  13  is fitted around the periphery of the cylindrical retainer  12  and rotationally supported by the cylindrical retainer  12 . Further, a second rotational cylinder  14  that is provided with a lever  14   a  is fitted around the periphery of the first rotational cylinder  13 . The first and second rotational cylinders  13  and  14  are fitted together, so that they are integrally rotated about the cylindrical retainer  12  when the lever  14   a  is rotated (denoted as “A” in  FIG. 1 ). Note that a sliding member  15  is inserted between the end face of the first rotational cylinder  13  and the flange  12   a.    
         [0017]    In the present embodiment, three notches  12   b  are formed on the flange  12   a  and tabs (not shown) that are provided on the scope-side connector are inserted therethrough. Namely, the scope-side connector is securely attached to the processor-side connector  10  by a bayonet mount mechanism, such that the tabs are engaged with the flange  12   a  when the lever  14   a  is rotated in the direction “A” as shown in  FIG. 1 . 
         [0018]    In  FIG. 1 , the initial position of the lever  14   a  is indicated by a solid line and the locking position, a position where the connectors are securely fixed together, is indicated by a phantom line. Further, in the locking position, the position of the first and second rotational cylinders  13  and  14  is retained by a plunger mechanism (not shown). 
         [0019]    On the casing  16 , at a position where the end face  13   a  of the base end of the first rotational cylinder  13  is located, a pin  17  that protrudes from the casing  16  is provided as a stop member. However, a recessed portion is formed along the arcuate section of the end face  13   a  so that the pin  17  is prevented from contact with the end face  13   a  within the range “θ” of  FIG. 1 . Namely, the range of rotational operation of the lever  14   a  is restricted by the contact between the pin  17  and the either edges of the recessed portion. 
         [0020]    Further, a sliding plate (the linear movable member)  18  formed of a thin plate is laid on the surface of the casing  16 . In the present embodiment, the sliding plate  18  is provided with two guide slits  18   a  and  18   b.  Pins  19   a  and  19   b,  which are screwed on the casing  16 , engages with each of the guide slits  18   a  and  18   b  so that the sliding plate  18  is retained but linearly movable along the length of the guide slits  18   a  and  18   b  (a direction “B” of  FIG. 1 ). 
         [0021]    The sliding plate  18  is provided with bent portions  18   c  and  18   d.  The bent portion  18   c  is folded outwards toward the first rotational cylinder  13  and extends inside the recessed portion, which is formed on the end face  13   a  of the base end of the first rotational cylinder  13 . On the other hand, the bent portion  18   d  is folded inwards toward the casing  16 . Further, the plane of the bent portion  18   d  is arranged parallel with the axes of the guide slits  18   a  and  18   b,  and the plane of the bent portion  18   c  is arranged perpendicular to the axes. 
         [0022]    When the lever  14   a  is rotated in the direction “A” from its initial position and the first rotational cylinder  13  is rotated in the clockwise direction, one edge of the recessed portion on the end face  13  of the base end of the first rotational cylinder  13  engages the bent portion  18   c.  Thereby, the sliding plate  18  is urged toward the upper-left side along the guide slits  18   a  and  18   b  in  FIG. 1 . 
         [0023]    Note that the initial position of the sliding plate  18 , i.e., the position of the sliding plate  18  when the lever  14   a  is at its initial position, is indicated by a solid line. On the other hand, the locking position of the sliding plate  18 , i.e., the position of the sliding plate  18  when the lever  14   a  is rotated to the locking position, is indicated by a phantom line. Further, the direction of linear motion of the sliding plate  18  at the position where an edge of the recessed portion and the bent portion  18   c  engage, is a tangent of an arc centered on the axis of the first and second rotational cylinders  13  and  14 . 
         [0024]    Biasing members  20  and  21  are provided respectively on the first rotational cylinder  13  and the sliding plate  18 , so that each of the members is biased from the fastening position to the initial position. Namely, the first rotational cylinder  13  is rotationally biased by a torsion spring  20  in the counter direction of the direction “A” (the counter clockwise direction in  FIG. 1 ). Additionally, the sliding plate  18  is biased by a spring  21  in the lower-right direction along the direction “B” in  FIG. 1 , thereby, the sliding plate  18  abuts the edge of the recessed portion of the end face  13   a.    
         [0025]    Note that one end  20   a  of the torsion spring  20  engages the first rotational cylinder and the other end  20   b  is fixed to the casing  16  via a retainer (not shown). Further, one end  21   a  of the spring  21  is attached to the bent portion  18   d  and the other end  21   b  is attached to a retainer  22  that is fixed to the casing  16 . 
         [0026]    Referring to  FIGS. 2 and 3 , the structures that are utilized to detect whether the lever  14   a  has rotated to the locking position will be explained.  FIG. 3  is a plan view only illustrating the relationship between the casing  16 , the sliding plate  18 , and a sensor  23 . 
         [0027]    As shown in  FIGS. 2 and 3 , a photointerrupter, which is a non-contact type area sensor, is positioned inside the casing  16  as the sensor  23 . The sensor  23  is so arranged to emit light in a direction perpendicular to the linear motion of the sliding plate  18  and the bent portion  18   d.  The bent portion  18   d  is caused to pass between the light emitter and the light receiver of the sensor  23  during the linear motion of the sliding plate  18 . 
         [0028]    Namely, when the sliding plate  18  is at its initial position, the bent portion  18   d  does not interrupt the light of the sensor  23 . Thus, when the lever  14   a  is rotated and the sliding plate  18  reaches the locking position, the bent portion  18   d  is positioned between the light emitter and the light receiver of the sensor  23 , and interrupts the light. Consequently, the fact that the lever  14   a  has been rotated to the locking position is detected. 
         [0029]    As described above, according to the present embodiment, the point when the lever has reached the locking position is determined by detecting the position of the sliding plate, which is cooperated by the rotation of the lever, so that the condition of whether or not the connectors are locked together is are more reliably detected. Further, the effect of positional variance of the rotational members, which is caused by tolerance bore in the rotational mechanism, is also reduced so that a fine adjustment, which is usually necessary to carry out when assembling the sensor, becomes unnecessary. 
         [0030]    Although the embodiment of the present invention has been described herein with reference to the accompanying drawings, obviously many modifications and changes may be made by those skilled in this art without departing from the scope of the invention. 
         [0031]    The present disclosure relates to subject matter contained in Japanese Patent Application No. 2006-131594 (filed on May 10, 2006), which is expressly incorporated herein, by reference, in its entirety.