Abstract:
A surgery equipment holding device comprises a holder for holding surgical equipment, a bar connected to the holder, a brake which operatively engages the bar for stopping movement of the bar, and a pair of switches for switching being an active state and an inactive state of the brake. The surgery equipment holding device is characterized in the operation thereof at the time of disengaging the fixation state, and exhibits excellent operability.

Description:
[0001]    This application claims benefit of Japanese Application No. 2001-152922 filed on May 22, 2001, the contents of which are incorporated by this reference.  
         BACKGROUND OF THE INVENTION  
         [0002]    1. Field of the Invention  
           [0003]    The present invention relates to a surgery equipment holding device for holding surgery equipment, and particularly relates to a surgery equipment holding device with excellent operability, that is characterized in the operation thereof at the time of disengaging the fixation state.  
           [0004]    2. Description of the Related Art  
           [0005]    In recent years, surgery equipment holding devices which hold surgery equipment instead of surgeons have come into use. Such surgery equipment holding devices are configured having an arm portion serving as change holding means, joints serving as fixation maintaining means disposed at the arm portion, and switches serving as fixation disengaging instructing means.  
           [0006]    Appropriately operating the switches changes the state of the joints between disengaged and fixed states. That is to say, moving the surgery equipment to a desired position and fixing it there can be performed by operating switches.  
           [0007]    For example, DE 295 11 899 UI and Japanese Patent No. 2,843,507 have configurations wherein the fixed state of the joints is disengaged by a surgeon operating switches.  
           [0008]    Also, the second embodiment disclosed in Japanese Unexamined Patent Application Publication No. 7-227398 discloses a surgery equipment holding device wherein the balance of an endoscope is maintained even in the event that the fixed state of the joints disposed on the arm portion is disengaged, by means of the surgery equipment holding device comprising an electromagnetic brake and counter balance.  
           [0009]    Further, with the device for holding surgery equipment disclosed in EP 0 293 760 B1, two mode switches are provided. One mode switch is a first mode to immediately disengage the fixed state of the joints. The other mode switch is a second mode exhibiting a holding force wherein the joints disposed on the arm portion can hold an endoscope and also wherein the surgeon can move the endoscope.  
           [0010]    However, with the surgery equipment holding devices disclosed in the aforementioned DE 295 11 899 UI and the aforementioned Japanese Patent No. 2,843,507, at the point that the surgeon operates switches to move the endoscope, the fixed state of the joints is immediately disengaged.  
           [0011]    Accordingly, in the event that the surgeon operates switches to move the field of view of the endoscope, the fixed state is immediately disengaged, which suddenly places the weight of the endoscope and the arm portion onto the hand of the surgeon holding the endoscope. The surgeon is unable to respond to such sudden change of load and the tip of the endoscope undesirably moves. Accordingly, the surgeon loses the field of view prior to disengaging the fixation, and thus must perform the task of regaining the field of view. This has been a problem which has led to lowered surgery efficiency.  
           [0012]    Also, with the surgery equipment holding device disclosed in the aforementioned Japanese Unexamined Patent Application Publication No. 7-227398, in the event that the surgeon operates switches, the fixed state of the joints is immediately disengaged. This suddenly places the force of the hand of the surgeon on the arm portion, and the same problem as described above occurs since the arm portion which is balanced is moved thereby.  
           [0013]    Further, with the surgery equipment holding device disclosed in EP 0 293 760 B1, in the event that the surgeon specifies the second mode, the endoscope is held with a predetermined force, which takes care of the problem wherein the tip of the endoscope moves. However, with cases wherein the endoscope must be moved frequently during the surgery, such as with brain surgery for example, using this device causes the problem that the surgeon must move the endoscope against the resistance of the fixing force every time. This places a load on the hand and arm of the surgeon. Also, operations for moving the endoscope minute distances against the resistance of the fixing force have been difficult.  
           [0014]    On the other hand, in the event that the surgeon specifies the first mode, the fixing force of the joints is immediately disengaged, so the same problem as described above occurs.  
           [0015]    Also, the configurations of placement positions of the switches of the conventional devices for holding surgery equipment do not take into consideration the axial direction of insertion of the endoscope. In other words, the configuration has been such that the relative position thereof changes according to the placement of the arm.  
           [0016]    Accordingly, the surgeon cannot instantaneously know the direction which the endoscope is facing. Accordingly, there has been a problem in that it takes time to move the endoscope in the intended direction.  
           [0017]    Also, equipment used for brain surgery and the like generally has a form wherein the surgeon pinches the equipment between his/her thumb and index finger. However, with conventional devices for holding surgery equipment, the grasping direction and insertion operating direction have differed with such equipment. In addition, unlike such equipment, the switches are in one location, so the surgeon tends not to be at ease with operating the surgery equipment holding device.  
         SUMMARY OF THE INVENTION  
         [0018]    Accordingly, it is an object of the present invention to provide a surgery equipment holding device wherein, at the time of operating switches to disengage the fixed state, a sudden load is prevented from being placed on the hand of the surgeon holding the surgical equipment or on the surgical equipment being held in the surgeon&#39;s hand.  
           [0019]    It is another object of the present invention to provide a surgery equipment holding device with excellent operability.  
           [0020]    To this end, a surgery equipment holding device according to the present invention comprises: a holder for holding surgical equipment; a bar connected to the holder; a brake which operatively engages the bar for stopping movement of the bar; and a switch for switching being an active state and an inactive state of the brake.  
           [0021]    The above and other objects, features and advantages of the invention will become more clearly understood from the following description referring to the accompanying drawings. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0022]    [0022]FIGS. 1 through 5 relate to a first embodiment of the present invention, wherein:  
         [0023]    [0023]FIG. 1 is a diagram illustrating a schematic configuration of a surgery equipment holding device;  
         [0024]    [0024]FIG. 2 is a diagram illustrating the state of the surgery equipment holding device holding a therapeutic device in the equipment holding portion thereof;  
         [0025]    [0025]FIG. 3 is a diagram explaining the structure of a fluid brake;  
         [0026]    [0026]FIG. 4A is a diagram explaining the structure of a fluid control unit;  
         [0027]    [0027]FIG. 4B is a diagram explaining the configuration of the fluid control unit provided with a variable diaphragm;  
         [0028]    [0028]FIG. 5 is a block diagram explaining the primary configuration of the surgery equipment holding device;  
         [0029]    [0029]FIG. 6 is a block diagram explaining the configuration of the surgery equipment holding device according to a modification of the first embodiment;  
         [0030]    [0030]FIG. 7 is a block diagram explaining another configuration of the surgery equipment holding device according to a second embodiment of the present invention;  
         [0031]    [0031]FIGS. 8 and 9 relate to a third embodiment of the present invention, wherein:  
         [0032]    [0032]FIG. 8 is a diagram explaining another configuration of the surgery equipment holding device;  
         [0033]    [0033]FIG. 9 is a block diagram explaining the configuration of the surgery equipment holding device;  
         [0034]    [0034]FIGS. 10 through 12B relate to a fourth embodiment of the present invention, wherein:  
         [0035]    [0035]FIG. 10 is a diagram explaining yet another configuration of the surgery equipment holding device;  
         [0036]    [0036]FIG. 11 is a cross-sectional diagram explaining the configuration of the grasping portion;  
         [0037]    [0037]FIG. 12A is a block diagram explaining yet another configuration of the surgery equipment holding device;  
         [0038]    [0038]FIG. 12B is a block diagram explaining yet another configuration of the surgery equipment holding device;  
         [0039]    [0039]FIGS. 13 through 14B relate to a fifth embodiment of the present invention, wherein:  
         [0040]    [0040]FIG. 13 is a diagram explaining the principal configuration of the surgery equipment holding device;  
         [0041]    [0041]FIG. 14A is a block diagram explaining the position where the control circuit is disposed;  
         [0042]    [0042]FIG. 14B is a diagram explaining the position where the control circuit is disposed; and  
         [0043]    [0043]FIG. 15 is a diagram explaining a modification of the fifth embodiment. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0044]    A first embodiment of the present invention will now be described with reference to FIGS. 1 through 5.  
         [0045]    As shown in FIG. 1, a surgery equipment holding device according to the present invention has, for example, an endoscope  1  as a device for observing the part of the body which is the object of the surgery. A television camera head  2  having a CCD for example for picking up optical images of observed parts is mounted on an eyepiece la of the endoscope  1 . Images signals of the optical images converted by the unshown CCD provided to the television camera head  2  are generated as video signals at a controller  3  which is a video signals processing device. The video signals generated at the controller  3  are output to a monitor  4 . Thus, endoscope images of the part observed are displayed on the screen of the monitor  4 .  
         [0046]    The endoscope  1  is held by a holding arm  5  serving as change holding means. The holding arm  5  is of a configuration which allows the position and direction of the endoscope  1  being held to be changed.  
         [0047]    Disposed on the tip side of the holding arm  5  which is one edge thereof are an equipment holding portion  6  for holding the endoscope  1 , and a grasping portion  7  for the surgeon to grasp. On the other hand, an attaching portion  9  is provided to the other end of the holding arm  5 , for being fixed to a surgery table  8 , for example.  
         [0048]    While the present embodiment is described with the endoscope  1  as an example of the surgery equipment held by the equipment holding portion  6 , therapeutic devices such as forceps  100 , a type of surgical equipment, may be held by the equipment holding portion  6 , as shown in FIG. 2.  
         [0049]    The holding arm  5  has a first arm  10   a,  a second arm  10   b,  and a third arm  10   c,  serially linked from the attaching portion  9  side. A first rod  11   a  and a second rod  11   b  are disposed between the first arm  10   a  and the second arm  10   b,  and between the second arm  10   b  and the third arm  10   c,  respectively.  
         [0050]    A first fluid brake  12   a,  a second fluid brake  12   b,  a third fluid brake  12   c,  and a fourth fluid brake  12   d,  serving as fixation maintaining means are disposed at the joint portions between the first arm  10   a  and first rod  11   a,  second arm  10   b  and the first rod  11   a,  the second arm  10   b  and second rod  11   b,  and third arm  10   c  and the second rod  11   b,  respectively.  
         [0051]    A first switch  13   a  and second switch  13   b  are provided as a pair, as fixation disengaging instructing means, to the grasping portion  7 . The first switch  13   a  and the second switch  13   b  are disposed so as to be in planar symmetrical positional relation across a plane  1   c,  the hatched portion in the figure, which contains the insertion axis  1   b  of the endoscope  1 .  
         [0052]    The first switch  13   a  and second switch  13   b  are electrically connected to a fluid control unit  14  which is a fixation force control means. A first fluid hose  16   a  and second fluid hose  16   b,  which are channels for a pressured fluid, extend from the fluid control unit  14 .  
         [0053]    The end of the second fluid hose  16   b  is coupled to a fluid pressure source  15  for supplying compressed air or compressed nitrogen gas, commonplace in surgery rooms. On the other hand, the end of the first fluid hose  16   a  branches into several parts at the base end side. The branched ends each couple with the first fluid brake  12   a,  second fluid brake  12   b,  third fluid brake  12   c,  and fourth fluid brake  12   d.    
         [0054]    The first switch  13   a  and second switch  13   b  are known push-button switches for example, and are contact switches having contacts. The first switch  13   a  and second switch  13   b  are electrically serially connected to a later-described control circuit  35  provided within the fluid control unit  14 .  
         [0055]    Now, the structure of the first fluid brake  12   a  will be described with reference to FIG. 3.  
         [0056]    Note that the structure of the second fluid brake  12   b,  third fluid brake  12   c,  and fourth fluid brake  12   d,  are the same as that of the first fluid brake  12   a.  Accordingly, the structure of the first fluid brake  12   a  alone will be described, and that of the second fluid brake  12   b,  third fluid brake  12   c,  and fourth fluid brake  12   d  will be omitted.  
         [0057]    As shown in the figure, the first arm  10   a  of the first fluid brake  12   a  has a hollow structure. Disposed within the first arm  10   a  are a generally-spherically formed ball end  21  formed on the end of the rod  11   a  with a radius R, and a pressing portion  20  of a predetermined form.  
         [0058]    An abutting portion  17 , formed of the spherical face having a radius R, is provided at the tip of the inside of the first arm  10   a.  Accordingly, the ball end  21  comes into planar contact with this abutting portion  17 . Note that the point A in the figure represent the center of the abutting portion  17  and the ball end  21 .  
         [0059]    The pressing portion  20  comprises a pressing member  22 , a shaft  23 , and a piston  24 . The pressing member  22  has a pressing face for pressing the ball end  21 . The shaft  23  is integrally provided on the base face of the pressing member  22 . The piston  24  is integrally provided on the base face of the shaft  23 .  
         [0060]    A protrusion  18  is formed in the inside of the first arm  10   a.  A spring  25  is disposed between this protrusion  18  and the pressing member  22 , in a compressed state. Accordingly, the pressing force of the spring  25  acts to press the pressing member  22 . Consequently, the pressing member  22  pressing the ball end  21  causes the ball end  21  and the abutting portion  17  to be pressed one against another, so as to be in a fixed and held state.  
         [0061]    As shown in FIG. 3, a first o-ring  27   a  for maintaining an airtight state is disposed between the protrusion  18  and the shaft  23 . Also, a second o-ring  27   b  for maintaining an airtight state is disposed between the inner circumference of the piston  24  and the first arm  10   a.  Providing these o-rings  27   a  and  27   b  makes the space defined by the first arm  10   a  and shaft  23  and piston  24  to be an airtight space  28 . An inlet port  29  communicating with the airtight space  28  is formed in the piston  24 . The end of the hose  16   a  is communicably connected to this inlet port  29 .  
         [0062]    The structure of the fluid control unit  14  will be described with reference to FIGS. 4A and 5.  
         [0063]    As shown in these figures, an electromagnetic valve  30 , serving as known means for switching channels, is disposed in the fluid control unit  14 . The electromagnetic valve  30  has three ports  31   a,    31   b,  and  31   c,  serving as the input channel, discharge channel, and functioning channel, for the pressured fluid. A known solenoid  32  configured of a coil  33  and shaft  34  are provided to the electromagnetic valve  30 . The coil  33  of the solenoid  32  is electrically connected to the first switch  13   a  and second switch  13   b  via the control circuit  35 .  
         [0064]    A valve  36  is integrally provided on the tip side of the shaft  34 . In the event that this valve  36  is at the position indicated by solid lines in the figure, the port  31   b  and the port  31   a  are in a communicating state. On the other hand, in the event that the valve  36  is at the position indicated by dotted lines in the figure, the port  31   b  and the port  31   c  are in a communicating state. That is to say, the configuration is such that the channels are switched by the valve  36  moving.  
         [0065]    A spring  37  is disposed between the shaft  34  and a housing  38 . The valve  36  is placed at the position indicated by the solid lines due to the pressing force of this spring  37 .  
         [0066]    A known diaphragm  39 , capable of narrowing down the cross-sectional area of the fluid tube, is disposed between the port  31   c  of the electromagnetic valve  30  and an inlet port  40 . The inlet port  40  is coupled to a fluid pressure source  15  via a hose  16   b,  such that the connection is airtight, while allowing the fluid to pass through.  
         [0067]    The hose  16   a  is coupled to the port  31   b.  The base portion of the hose  16   a  is connected to the inlet port  40  communicating with the airtight space  28  formed at each of the first fluid brake  12   a,  second fluid brake  12   b,  third fluid brake  12   c,  and fourth fluid brake  12   d,  such that the connection is airtight, while allowing the fluid to pass through.  
         [0068]    The port  31   a  is opened to the atmosphere via an vent tube  41 .  
         [0069]    The cross-sectional area Qx(m 2 ) of the fluid channel of the diaphragm  39  and the cross-sectional area Qy(m 2 ) of the vent tube  41  are set in a relation such that  
         Qx≦Qy  
         [0070]    holds.  
         [0071]    Now, the operation of the surgery equipment holding device configured thus will be described.  
         [0072]    First, the fixation holding state of the surgery equipment holding device will be described.  
         [0073]    At the time of this fixation holding state, the first switch  13   a  and the second switch  13   b  are unpressed, and the valve  36  is situated at the position indicated by the solid line in the figure by the pressing force of the spring  37 . Accordingly, the port  31   b  and the port  31   a  are in a communicating state.  
         [0074]    Thus, the vent tube  41  and the airtight space  28  are communicating via the port  31   a,  port  31   b,  and hose  16   a.  In other words, the airtight space  28  is released to the Atmosphere.  
         [0075]    Consequently, the pressing portions  20  within the first fluid brake  12   a,  second fluid brake  12   b,  third fluid brake  12   c,  and fourth fluid brake  12   d  are pressed against the abutting portion  17  side by the pressing force of the spring  25 . As a-result, the ball end  21  is pressed and fixed against the abutting portion  17  by a fixing force of F (N), by the pressing member  22  making up the pressing portion  20 .  
         [0076]    That is to say, the endoscope  1  is fixed and held in a constant position, due to the rod  11   a  and the rod  11   b  being in a fixed state.  
         [0077]    Now, in this fixation state, the pressured fluid in the fluid pressure source  15  is in a pressured and filled state near to around the port  31   c,  via the hose  16   b,  inlet port  40 , and diaphragm  39 .  
         [0078]    Next, the operation for causing the fixed and held endoscope  1  to move will be described.  
         [0079]    In the event of moving the endoscope  1 , the fixation holding state of the first fluid brake  12   a,  second fluid brake  12   b,  third fluid brake  12   c,  and fourth fluid brake  12   d  is disengaged. To this end, the surgeon presses and operates the first switch  13   a  and the second switch  13   b  disposed on the grasping portion  7 .  
         [0080]    Note that the relative positional relation between the first switch  13   a  and the second switch  13   b  disposed on the grasping portion  7  and the endoscope  1  is always the same, regardless of the attitude of the holding arm  5 .  
         [0081]    Also, as described above, the first switch  13   a  and the second switch  13   b  are disposed so as to be in plane symmetrical positional relation across a plane  1   c  which contains the insertion axis  1   b  of the endoscope  1 . Accordingly, the surgeon can operate while grasping the grasping portion  7  and pinching the first switch  13   a  and the second switch  13   b  with the thumb and index finger.  
         [0082]    The surgeon simultaneously pressing and operating the first switch  13   a  and the second switch  13   b  brings the electromagnetic valve  30  to action. The action of the electromagnetic valve  30  causes the valve  36  to move against the pressing force of the spring  37  due to a solenoid  32  from the position indicated by solid lines to the position indicated by dotted lines. Thus, the port  31   b  and the port  31   c  are in a communicating state. This causes the pressured fluid which had been filled in a pressurized state up to the port  31   c  to flow into the airtight space  28  via the port  31   b  Hand the hose  16   a.  That is to say, the pressured fluid continues to pass through the diaphragm  39  formed with a cross-sectional area Qx(m 2 ) into the airtight space  28 , until an isopiestic state is attained between the airtight space  28  and the fluid pressure source  15 .  
         [0083]    Once the pressure within the airtight space  28  begins to rise, reaction force is generated at the piston  24  against the pressing force of the spring  25  pressing the pressing member  22 . That is, the pressing force pressing the ball end  21  of the pressing portion  20  gradually drops. Finally, the pressed fixation state of the ball end  21  which had been pressed and fixed against the abutting portion  17  by the pressing portion  20 , is disengaged.  
         [0084]    This allows the ball ends  21  disposed within the first fluid brake  12   a,  second fluid brake  12   b,  third fluid brake  12   c,  and fourth fluid brake  12   d  to rotate on the center point A. That is to say, the first rod  11   a  and the second rod  11   b  become movable. Thus, the surgeon can move the endoscope  1  to a desired position.  
         [0085]    Next, description will be made regarding a case wherein the surgeon fixes the endoscope  1  again.  
         [0086]    Upon moving the endoscope  1  to the desired position, the surgeon releases his/her fingers from the first switch  13   a  and the second switch  13   b  to fix and hold the position of the endoscope  1 . This causes the valve  36  of the electromagnetic valve  30  to return from the position indicated by dotted lines to the position indicated by solid lines, due to the pressing force of the spring  37 . Thus, the port  31   a  and the port  31   b  communicate.  
         [0087]    At this time, the pressured fluid filling the airtight space  28  immediately is released into the atmosphere through the vent tube  41  formed with a cross-sectional area Qy(m 2 ), via the ports  31   b  and  31   a.  Consequently, the reaction force decreases, the pressing portion  20  is pressed by the pressing force of the spring  25 , and the ball end  21  is pressed and fixed against the abutting portion  17 . Thus, the endoscope  1  is in a fixed and held state at the position to which the surgeon has moved it.  
         [0088]    That is to say, at the time of disengaging the fixation, the pressured fluid passes through the diaphragm  39  formed with a cross-sectional area Qx(m 2 ). Conversely, at the time of fixing, the pressured fluid passes through the vent tube  41  formed with a cross-sectional area Qy(m 2 ).  
         [0089]    Now, the relation of Qx&lt;&lt;Qy has been set between Qx and Qy, so the amount of fluid passing through these channels per unit time is in the same relation as with the relation of cross-sectional area. That is, the difference set here in the amount of fluid passing through causes the disengaging action of the surgery equipment holding device to be carried out gradually. On the other hand, the fixing action of the surgery equipment holding device is performed rapidly. Accordingly, there is no sudden placing of a load on the hand of the surgeon at the time of disengaging the fixation, while the endoscope is speedily fixed at the time of fixation.  
         [0090]    In this way, the cross-sectional area of the channels through which the pressured fluid passes at the time of disengaging fixation and at the time of fixing is set such that the cross-sectional area of the channel through which the pressured fluid passes at the time of disengaging fixation is smaller than the cross-sectional area of the channel through which the pressured fluid passes at the time of fixing, so that on one hand, while the surgeon can disengage the fixed state of the endoscope without any sudden placing of holding load on the hand of the surgeon, on the other hand, the endoscope can be speedily set in a fixed state at the time of fixing.  
         [0091]    Thus, at the time of moving the surgery equipment, the surgeon can smoothly move the surgery equipment to the desired position without losing sight of the part of the body to be observed or treated. Accordingly, the working time can be reduced, the fatigue of the surgeon can be lightened, and surgery efficiency improves greatly.  
         [0092]    Also, control of fixation disengagement and fixing can be performed using the pressured fluid of a fluid pressure source normally installed in surgery rooms, so there is no need to prepare a new fluid pressure source or install complicated control circuits, and accordingly ease-of-use is facilitated.  
         [0093]    Further, a small and simple structure can be realized, by adopting simple electrical contact switches as the switches. In addition, by electrically connecting a pair of switches serially to the control circuit instruction signals can be surely prevented from being output in the event that only one switch is operated.  
         [0094]    Also, the relative positional relation between the switches and the plane containing the axis of the endoscope is constant, thereby solving the problem of the surgeon having to confirm the position each time when moving the surgery equipment held by the surgery equipment holding device to a desired position and fixing the surgery equipment thereat, so time efficiency in the surgery can be achieved as well.  
         [0095]    Note that in the present embodiment, the fluid pressure source  15  is described as a configuration using compressed air or compressed nitrogen gas or the like installed in the A surgery room, but the pressured fluid is not restricted to these, and oil, viscous fluids, etc., capable of being compressed, may be used.  
         [0096]    Also, with the present embodiment, the configuration indicated uses an electromagnetic valve  30  for switching channels, but the switching of the channels is not restricted to an electromagnetic valve; rather, any channel switching means capable of switching channels according to instructions from the first switch  13   a  and second switch  13   b  is sufficient, and another example will be described later.  
         [0097]    Next, a modification of the first embodiment will be described with reference to FIG. 4B.  
         [0098]    As shown in the figure, with the present embodiment, the diaphragm  39  provided to the inlet port  40  in FIG. 4A has been changed to a variable diaphragm  39   a.  The variable diaphragm  39   a  allows the operator to set the fluid influx to A desired amount. That is to say, this variable diaphragm  39   a  allows the amount of influx of the fluid to the airtight space  28  to be suitably adjusted in increments of time. Consequently, the surgeon can set the time which elapses till the brakes are disengaged to a desired value, and can smoothly move the surgery equipment to the object part. Thus, according to the present embodiment, the operability of the device improves, and fatigue of the surgeon is alleviated.  
         [0099]    Further, in FIG. 4B, a variable diaphragm  39   b  is provided to the vent tube  41  as well, so that the operator an set the amount of fluid discharged to a desired amount. That is to say, this variable diaphragm  39   b  allows the amount of fluid discharged from the airtight space  28  to be suitably adjusted in increments of time. Consequently, the surgeon can set the time which elapses till the brakes are active, to a desired value.  
         [0100]    Now, it is generally held to be true that the time required for the brakes to become active should be as short as possible. However, it is also undeniable that there are timings which are intuitively acceptable and unacceptable according to individuals. In regard to this, the present embodiment allows the time for the fluid to flow into the airtight space  28  via the variable diaphragm  39   a  to be adjusted, and the variable diaphragm  39   b  can be adjusted to achieve matching with the capacity of the airtight space  28  itself, so a surgery equipment holding device capable of reducing fatigue, which is suitably operable and meets the preferences of each of multiple surgeons, can be provided.  
         [0101]    Note that in the event that the only object of the surgeon is to smoothly move the surgery equipment to the object part, all that is necessary is to set the time until the brakes are disengaged. In other words, the object of the present embodiment can be achieved simply by adding the variable diaphragm  39   a  in order to adjust the timing of disengaging the brakes to the preference of the surgeon.  
         [0102]    Next, a modification of the first embodiment will be described with reference to FIG. 6.  
         [0103]    As shown in the figure, with the present embodiment, the configuration of the fluid control unit  14  serving as the fixing force control means has been changed as follows.  
         [0104]    With the fluid control unit  14 A according to the present embodiment, a directional diaphragm unit  42  is disposed between the port  31   b  of the electromagnetic valve  30  and the hose  16   a.  This directional diaphragm unit  42  comprises a diaphragm  43  and a check valve  44  which allows the fluid to only flow in the one direction indicated by the arrow.  
         [0105]    That is, the check valve  44  is provided such that only the fluid from the airtight spaces  28  formed in the first fluid brake  12   a,  second fluid brake  12   b,  third fluid brake  12   c,  and fourth fluid brake  12   d,  passes.  
         [0106]    Also, the cross-sectional area Qx 1  of the diaphragm  43  and the cross-sectional area Qy 1  of the check valve  44  are set in a relation such that  
         Qx 1 ≦Qy 1   
         [0107]    holds. That is to say, the relation is set such that the cross-sectional area of the channel through which the pressured fluid passes at the time of disengaging fixation is smaller than the cross-sectional area of the channel through which the pressured fluid passes at the time of fixing.  
         [0108]    The surgeon simultaneously pressing and operating the first switch  13   a  and the second switch  13   b  in order to disengage the fixed state of the endoscope  1  brings the electromagnetic valve  30  to action, and the port  31   b  and the port  31   c  communicate. This causes the pressured fluid to pass through the port  31   c  and port  31   b  and then flow into the directional diaphragm unit  42 . The pressured fluid which flows into the directional diaphragm unit  42  then passes through the diaphragm  48  and enters the airtight space  28  to act in the same manner as with the first embodiment.  
         [0109]    On the other hand, upon the surgeon releasing his/her fingers from the first switch  13   a  and the second switch  13   b  to fix and hold the position of the endoscope  1 , the pressured fluid filling the airtight space  28  immediately is released into the atmosphere, as with the first embodiment, primarily through the check valve  44 .  
         [0110]    That is to say, at the time of flowing into the airtight space  28 , the pressured fluid passes through the diaphragm  43  formed with a cross-sectional area Qx 1 . On the other hand, at the time of flowing out of the airtight space  28 , the pressured fluid passes through the check valve  44  formed with a cross-sectional area Qy 1 .  
         [0111]    Now, the relation of Qx1&lt;&lt;Qy1 has been set between Qx 1  and Qy 1 , so as with the first embodiment, causes the disengaging action of the surgery equipment holding device to be carried out gradually, and the fixing action of the surgery equipment holding device to be performed rapidly. That is to say, operations and advantages similar to those of the first embodiment can be obtained at the time of disengaging the fixation and at the time of fixing.  
         [0112]    In this way, a simple configuration that is easy to use can be realized by using a known diaphragm and check valve in the directional diaphragm unit.  
         [0113]    A second embodiment of the present invention will be described with reference to FIG. 7.  
         [0114]    Note that with the present embodiment, components common to the first embodiment will be denoted with the same reference numerals and description thereof will be omitted.  
         [0115]    As shown in the figure, the fluid pressure source  15  according to the present embodiment is coupled to the port  31   c  of the electromagnetic valve  30  via the hose  16   b.  The port  31   b  of the electromagnetic valve  30 , and an inlet port  29   a  communicating with the airtight spaces  28  formed at each of the first fluid brake  12   a,  second fluid brake  12   b,  third fluid brake  12   c,  and fourth fluid brake  12   d,  are coupled by an inlet hose  16   c.  The fluid channel of the port  31   a  of the electromagnetic valve  30  according to the present embodiment is closed off.  
         [0116]    On the other hand, a discharge port  29   b,  which is a fluid channel, is provided at the airtight spaces  28  communicating with the inlet ports  29   a  of the first fluid brake  12   a,  second fluid brake  12   b,  third fluid brake  12   c,  and fourth fluid brake  12   d.    
         [0117]    One end of a vent hose  16   d  making up the fluid channel is coupled to the discharge port  29   b.  The other end of the vent hose  16   d  is coupled to a port  31   d  of an electromagnetic valve  30 A having a configuration generally the same as that of the electromagnetic valve  30 .  
         [0118]    Now, the relation is set such that the cross-sectional area Qx 2  of the inlet hose  16   c  is smaller than the cross-sectional area Qy 2  of the vent hose  16   d.    
         [0119]    The electromagnetic valve  30 A has, in addition to the port  31   d,  a port  31   e  released to the atmosphere. The port  31   d  and port  31   e  of the electromagnetic valve  30 A are of a configuration controllable by a control circuit  35 A.  
         [0120]    The first switch  13   a  and the second switch  13   b  are electrically connected to the control circuit  35 A. The control circuit  35 A is electrically connected to each of the electromagnetic valve  30  and the electromagnetic valve  30 A. In the present embodiment, the control circuit  35 A, the electromagnetic valve  30  and the electromagnetic valve  30 A, and the inlet hose  16   c  and the vent hose  16   d  make up the fixing force control means.  
         [0121]    Now, the operation of the surgery equipment holding device configured thus will be described.  
         [0122]    First, the surgeon presses and operates the first switch  13   a  and the second switch  13   b.  As a result, at the control circuit  35 A, the port  31   c  and port  31   b  provided on the electromagnetic valve  30  are in a communicating state, while the channel to the port  31   d  of the electromagnetic valve  30 A is closed off. Accordingly, the pressured fluid supplied from the fluid pressure source  15  passes through the hose  16   b,  electromagnetic valve  30 , and inlet hose  16   c,  and flows into the airtight space  28 , thereby raising the internal pressure. Consequently, as with the first embodiment, the fixing force of the first fluid brake  12   a,  second fluid brake  12   b,  third fluid brake  12   c,  and fourth fluid brake  12   d  drop, attaining a fixation disengagement state.  
         [0123]    Next, when the surgeon releases the first switch  13   a  and the second switch  13   b,  at the control circuit  35 A, the port  31   a  and port  31   b  of the electromagnetic valve  30  are in a communicating state, while the port  31   d  and port  31   e  of the electromagnetic valve  30 A are also in a communicating state. At this time, the fluid channel to the port  31   c  is closed off.  
         [0124]    Accordingly, the pressured fluid filling the airtight space  28  is released into the atmosphere via the vent hose  16   d,  port  31   d,  and port  31   e.  Consequently, as with the first embodiment, the first fluid brake  12   a,  second fluid brake  12   b,  third fluid brake  12   c,  and fourth fluid brake  12   d  are in a fixed state.  
         [0125]    Now, the cross-sectional area of the inlet hose  16   c  is set to be smaller than the cross-sectional area of the vent hose  16   d,  so the amount of change in pressure of the airtight space  28  per time increment is smaller at the time of disengaging the fluid brake fixation. Consequently, operations and advantages the same as those of the first embodiment can be obtained.  
         [0126]    In addition, with the present embodiment, a common fluid channel for pressured fluid to pass through at the fixation action time and the fixation disengagement action time is not configured. Accordingly, the channel for pressured fluid at the fixation action time and the channel for pressured fluid at the fixation disengagement action time are independently configured. Accordingly, action control for each can be independently designed and disposed, thereby realizing handy and easy high-precision control.  
         [0127]    While the present embodiment is described with a configuration using an inlet hose  16   c,  other configurations may be used, such as one with a diaphragm disposed instead of the inlet hose  16   c.    
         [0128]    A third embodiment of the present invention will be described with reference to FIGS. 8 and 9.  
         [0129]    Note that with the present embodiment, components common to the above-described embodiments will be denoted with the same reference numerals and description thereof will be omitted.  
         [0130]    As shown in FIG. 8, with the present embodiment, mechanical switches denoted by reference numerals  50   a  and  50   b  are provided at the equipment holding portion  6 . The mechanical switches  50   a  and  50   b  are fixation disengaging instructing means capable of mechanically controlling the pressured fluid which is the acting energy of the first fluid brake  12   a,  second fluid brake  12   b,  third fluid brake  12   c,  and fourth fluid brake  12   d,  which are fixation maintaining means. The mechanical switches  50   a  and  50   b  are disposed at axially symmetrical positions as to the insertion axis  1   b  of the endoscope  1 .  
         [0131]    As shown in FIG. 9, known mechanical valves, denoted by reference numerals  51  and  52 , are provided at the mechanical switches  50   a  and  50   b.  These mechanical valves  51  and  52  are respectively joined to the mechanical switches  50   a  and  50   b  which are manual push-button switches integrally joined to the axis  34  instead of the electromagnetic valve  30  shown in FIG. 4A according to the first embodiment.  
         [0132]    As with the electromagnetic valve  30  in the first embodiment, the mechanical valves  51  and  52  have respective input ports  51   a  and  52   a,  discharge ports  51   b  and  52   b,  and functioning ports  51   c  and  52   c.    
         [0133]    Now, the operation of the mechanical valve  51  will be described. Note that the action of the mechanical valve  52  is the same as the action of the mechanical valve  51 . Accordingly, only the mechanical valve  51  will be described here, and description of the mechanical valve  52  will be omitted.  
         [0134]    The mechanical valve  51  is channel switching means, and normally, in the state that the mechanical switch  50   a  is not pressed, the discharge port  51   b  and the functioning port  51   c  are in a communicating state. When the mechanical switch  50   a  is in a pressed state, the input port  51   a  and the functioning port  51   c  are in a communicating state.  
         [0135]    A hose  55  extending from the fluid pressure source  15  is coupled to the input port  51   a  of the mechanical valve  51 , such that the connection is airtight, while allowing the fluid to pass through. The functioning port  51   c  of the mechanical valve  51  and the input port  52   a  of the mechanical valve  52  are coupled via a hose  56 , such that the connection is airtight, while allowing the fluid to pass through.  
         [0136]    Further, a hose  57  is coupled to the functioning port  52   c  of the mechanical valve  52 , and each of the branched ends of the hose  57  are connected to one end of directional diaphragm units  42   a,    42   b,    42   c,  and  42   d,  each having a configuration that same as the directional diaphragm unit  42  described in the first embodiment.  
         [0137]    The other end of the directional diaphragm units  42   a,    42   b,    42   c,  and  42   d,  and the airtight space  28  of the first fluid brake  12   a,  second fluid brake  12   b,  third fluid brake  12   c,  and fourth fluid brake  12   d,  respectively communicate via hoses  58   a,    58   b,    58   c,  and  58   d.    
         [0138]    Note that both discharge ports  51   b  and  52   b  are opened to the atmosphere.  
         [0139]    Also, the check valves  44  provided within the directional diaphragm units  42   a,    42   b,    42   c,  and  42   d  are disposed so that the pressured fluid within the airtight spaces  28  will pass.  
         [0140]    Further, the diameter dimensions of diaphragms  43   a,    43   b,    43   c,  and  43   d,  disposed within the directional diaphragm units  42   a,    42   b,    42   c,  and  42   d,  are set such that the relation Φa&lt;Φb&lt;Φc&lt;Φd holds.  
         [0141]    With the present embodiment, the directional diaphragm units  42   a,    42   b,    42   c,  and  42   d,  and the mechanical valves  51  and  52  make up the fluid control unit  53  serving as the fixation force control means.  
         [0142]    The operation of the surgery equipment holding device configured as described above will now be described.  
         [0143]    First, description will be made regarding a case of the surgeon moving the endoscope  1 .  
         [0144]    In the event that the surgeon operates the mechanical switch  50   a,  the input port  51   a  and the functioning port  51   c  are placed in a communicating state at the mechanical valve  51 . Also, in the event that the surgeon operates the mechanical switch  50   b,  the input port  52   a  and the functioning port  52   c  are placed in a communicating state at the mechanical valve  52 .  
         [0145]    In the event that the surgeon operates both the mechanical switch  50   a  and the mechanical switch  50   b  simultaneously, the pressured fluid from the fluid pressure source  15  passes through the hose  55 , input port  51   a,  functioning port  51   c,  hose  56 , input port  52   a,  and functioning port  52   c,  in that order, and flows into the hose  57 . The pressured fluid which has flowed into the hose  57  flows into the airtight space  28  of the first fluid brake  12   a,  second fluid brake  12   b,  third fluid brake  12   c,  and fourth fluid brake  12   d,  via the directional diaphragm units  42   a,    42   b,    42   c,  and  42   d  which are disposed in parallel on the hose  57 .  
         [0146]    Now, the relation of the moment Ma, Mb, Mc, and Md, as to the load necessary for holding the endoscope, with regard to the first fluid brake  12   a,  second fluid brake  12   b,  third fluid brake  12   c,  and fourth fluid brake  12   d,  is Ma&gt;Mb&gt;Mc&gt;Md.  
         [0147]    That is to say, the moment Md placed on the fulcrum A within the fourth fluid brake  12   d  is the load from the third arm  10   c  to the endoscope  1 . In comparison, the moment Mc placed on the fulcrum A within the third fluid brake  12   c  is the load from the rod  11   b  to the endoscope  1 . Also, the moment Mb placed on the fulcrum A within the second fluid brake  12   b  is the load from the second arm  10   b  to the endoscope  1 , and the moment Ma placed on the fulcrum A within the first fluid brake  12   a  is the load from the rod  11   a  to the endoscope  1 .  
         [0148]    On the other hand, the relation Φa&lt;Φb&lt;Φc&lt;Φd holds for the diaphragms  43   a,    43   b,    43   c,  and  43   d,  with the channel cross-sectional areas being adjusted according to the moment Ma, Mb, Mc, and Md relating to the first fluid brake  12   a,  second fluid brake  12   b,  third fluid brake  12   c,  and fourth fluid brake  12   d,  so as to act such that the first fluid brake  12   a,  second fluid brake  12   b,  third fluid brake  12   c,  and fourth fluid brake  12   d  all are disengaged simultaneously and at the same speed.  
         [0149]    Next, description will be made regarding a case of the surgeon fixing the endoscope  1 .  
         [0150]    When the surgeon releases the mechanical switches  50   a  and  50   b,  as with the first embodiment, the first fluid brake  12   a,  second fluid brake  12   b,  third fluid brake  12   c,  and fourth fluid brake  12   d  are immediately placed in a fixed state.  
         [0151]    That is to say, the fixation disengaging action of the surgery equipment holding device is carried out gradually, while the fixing action of the surgery equipment holding device is performed rapidly. Thus, at the time of disengaging, the fixed state of the endoscope can be disengaged without applying a sudden holding load on the hand of the surgeon, while on the other hand, the endoscope  1  can be rapidly fixed at the time of fixing.  
         [0152]    Thus, with the present embodiment, no electrical control is used whatsoever, so the configuration can be made even more simple.  
         [0153]    Also, the fixation disengaging speed can be set to be different according to the difference of moment relating to the fluid brakes, so an even more operable surgery equipment holding device can be provided, by arranging the fixation of the joints to be disengaged at the same speed as to the holding hand of the surgeon.  
         [0154]    Further, the mechanical switches are disposed axially symmetrical as to the insertion axis of the endoscope, resulting in a form where the surgeon grasps the endoscope itself. Accordingly, the surgeon can grasp the position on the endoscope even more easily than with the first embodiment.  
         [0155]    Accordingly, the problem of fatigue on the surgeon, which is caused by difference in operability wherein the relative positional relation between the switches and the surgery equipment differs from one surgical therapeutic device to another, can be lessened.  
         [0156]    A fourth embodiment of the present invention will be now described with reference to FIGS.  10  to  12 B.  
         [0157]    Note that with the present embodiment, components common to the above-described embodiments will be denoted with the same reference numerals and description thereof will be omitted.  
         [0158]    As shown in FIG. 10, the grasping portion  7  according to the present embodiment is configured of a holding member  61  and rotating member  60 . The holding member  61  is connected and fixed to the third arm  10   c.  The rotating member  60  has a configuration rotatably attached to the holding member  61 .  
         [0159]    As shown in FIG. 11, the rotating member  60  has a pipe-shaped form. The rotating member  60  is fit in between cylindrical protrusion  61   a  and  61   b  of the holding member  61 , and rotates freely with respect to the insertion axis  1   b  of the endoscope  1 .  
         [0160]    A first switch  13   a  and second switch  13   b  are provided at axially symmetrical positions as to the axis  1   b  of the endoscope  1 , on the perimeter of the rotating member  60 . The first switch  13   a  and second switch  13   b  are connected to a later-described fluid control unit denoted by reference numeral  63  in FIG. 12A, serving as fixing force control means.  
         [0161]    As shwon in FIG. 12A, the fluid control unit  63  comprises a control circuit  62 , a first electromagnetic valve  67  and second electromagnetic valve  68  similar to the electromagnetic valve  30  in the first embodiment, and a fluid transmission delay unit  64 .  
         [0162]    The first switch  13   a  and second switch  13   b  are electrically connected to the electromagnetic valves  67  and  68  respectively via the control circuit  62 . The fluid transmission delay unit  64  comprises ports  64   a  and  64   b  which are inlet/outlets for the fluid, with a long hose  65  of which tube length is long coupled. The long hose  65  is airtight and capable of passing fluid between the ports  64   a  and  64   b.    
         [0163]    The tube length of the hose  65  is set to that capable of exhibiting the later-described operations in comparison with the above-described hose  16   b,  specifically.  
         [0164]    The fluid pressure source  15  is coupled via the hose  16   a  to the input port  66  of the fluid control unit  63 , such that the connection is airtight, while allowing the fluid to pass through. The input port  66  and the input port  67   a  of the first electromagnetic valve  67  are coupled such that the connection is airtight, while allowing the fluid to pass through. The functional port  67   c  of the first electromagnetic valve  67  and the port  64   a  of the fluid transmission delay unit  64  are coupled such that the connection is airtight, while allowing the fluid to pass through.  
         [0165]    Also, the port  64   b  of the fluid transmission delay unit  64  and the input port  68   a  of the second electromagnetic valve  68  are coupled such that the connection is airtight, while allowing the fluid to pass through. Moreover, the functional port  68   c  of the second electromagnetic valve  68  and the hose  16   b  are coupled such that the connection is airtight, while allowing the fluid to pass through.  
         [0166]    The branched base of the hose  16   b  is coupled in parallel to the inlet port  29  of the airtight space  28  formed at the first fluid brake  12   a,  second fluid brake  12   b,  third fluid brake  12   c,  and fourth fluid brake  12   d,  such that the connection is airtight, while allowing the fluid to pass through. Also, the discharge ports  67   b  and  68   b  of the electromagnetic valves  67  and  68  are opened to the atmosphere.  
         [0167]    The operation of the surgery equipment holding device thus configured will now be described.  
         [0168]    In the state that the surgeon has not pressed the first switch  13   a  and second switch  13   b,  the functional port  67   c  and discharge port  67   b  of the electromagnetic valve  67 , and the functional port  68   c  and discharge port  68   b  of the electromagnetic valve  68  communicate. Accordingly, the airtight space  28  within the first fluid brake  12   a,  second fluid brake  12   b,  third fluid brake  12   c,  and fourth fluid brake  12   d,  and the interior of the hose  65  of the fluid transmission delay unit  64 , are opened to the atmosphere. Thus, as with the first embodiment, the first fluid brake  12   a,  second fluid brake  12   b,  third fluid brake  12   c,  and fourth fluid brake  12   d,  are in a fixed state.  
         [0169]    In the event of moving the endoscope  1 , the surgeon presses and operates the first switch  13   a  and second switch  13   b.  This causes the electromagnetic valves  67  and  68  within the fluid control unit  63  to operate in the same manner as with the first embodiment, via the control circuit  62 . That is to say, the input port  67   a  and the functional port  67   c  of the electromagnetic valve  67  communicate, and the input port  68   a  and the functional port  68   c  of the electromagnetic valve  68  communicate.  
         [0170]    Thus, the pressured fluid starts to flow in from the fluid pressure source  15 . The pressured fluid then passes through the hose  65  disposed at the fluid transmission delay unit  64 , and increases the pressure inside the airtight space  28  within the first fluid brake  12   a,  second fluid brake  12   b,  third fluid brake  12   c,  and fourth fluid brake  12   d.  As a result of this, the first fluid brake  12   a,  second fluid brake  12   b,  third fluid brake  12   c,  and fourth fluid brake  12   d  attain a fixation disengaged state, as with the first embodiment.  
         [0171]    Then, when the surgeon releases the first switch  13   a  and the second switch  13   b  to fix the endoscope  1 , the first switch  13   a  and the second switch  13   b  make transition to the original state before being operated.  
         [0172]    Consequently, the pressured fluid filling the airtight space  28  is discharged into the atmosphere from the discharge port  68   b  of the second electromagnetic valve  68 . On the other hand, the pressured fluid filling the hose  65  of the fluid transmission delay unit  64  is discharged into the atmosphere from the discharge port  67   b  of the first electromagnetic valve  67 .  
         [0173]    That is to say, the pressured fluid within the airtight space  28  must pass through the hose  65  of the fluid transmission delay unit  64  in the event that the surgeon moves the endoscope  1 , but does not pass through the hose  65  in the event that the surgeon fixes the endoscope  1 .  
         [0174]    Accordingly, the longer the hose  65  is, the longer the time required for the pressured fluid to pass through the hose  65 . Thus, when comparing the amount of change in pressure in the airtight space  28  per time increment for the first fluid brake  12   a,  second fluid brake  12   b,  third fluid brake  12   c,  and fourth fluid brake  12   d  to make transition to the disengaged state or the fixed state from the time of pressing or releasing the first switch  13   a  and the second switch  13   b,  the amount of change in pressure is clearly smaller at the time of disengaging the fixation than at the time to the fixed state.  
         [0175]    This means that, as with the above-described embodiments, the disengaging action of the surgery equipment holding device can be carried out gradually, while the fixing action of the surgery equipment holding device can be performed rapidly.  
         [0176]    Also, providing the switches at axially symmetrical positions as to the insertion axis of the endoscope obtains the same operations as with the third embodiment. Further, with the present embodiment, the switches are rotatable with respect to the insertion axis of the endoscope, so in the event that the position is such that the surgeon cannot readily press the switches, rotating the rotating member allows rotation with the relative positional relation maintained between the switches and the endoscope. Thus, the surgeon can change the position of the switches to an easily-operated position, thereby reducing fatigue of the surgeon and improving the efficiency of the surgery.  
         [0177]    Also, though the present embodiment has been described with a configuration using a hose for the fluid transmission delay unit, the same operations and advantages can be obtained with other arrangements, such as replacing the fluid transmission delay unit with a container such as a chamber  100  shown in FIG. 12B, or the diaphragm  39  and variable diaphragm  39   a  shown in FIGS. 4A and 4B.  
         [0178]    A fifth embodiment of the present invention will be now described with reference to FIGS.  13  to  14 B.  
         [0179]    The configuration of the present embodiment is an arrangement wherein the control unit of the second embodiment disclosed in Japanese Unexamined Patent Application Publication No. 07-227398 mentioned above as conventional art is replaced with a later-described control circuit  70 .  
         [0180]    As shown in FIG. 13, the surgery equipment holding device comprises electromagnetic brakes  71 ,  72 , and  73 , and counterweights  74  and  75 . In the event that the fixation state of the joints disposed on the arm portion is disengaged, the endoscope  1  maintains a balanced state by the counterweights  74  and  75 .  
         [0181]    As shown in FIG. 14A, the control circuit  70  serving as fixing force control means in the present embodiment is electrically connected and disposed between a switch  77  and the electromagnetic brakes  71 ,  72 , and  73 .  
         [0182]    The functional configuration of the control circuit  70  is such that, in the event that the switch  77  is pressed, the voltage increases as to the electromagnetic brakes  71 ,  72 , and  73 , at a predetermined voltage increase per time increment, dE (V/sec). On the other hand, in the event that the switch  77  is turned off, the voltage decreases at a predetermined voltage decrease dEs (V/sec).  
         [0183]    The present embodiment sets the relation dE≦dEs between dE and dEs in the present embodiment, so as to effect control.  
         [0184]    Further, with the present embodiment, in the event that the switch  77  is not operated, the electromagnetic brakes  71 ,  72 , and  73  are fixed by a magnetic force P 0  due to a permanent magnet  78  as shown in FIG. 14B.  
         [0185]    Upon the surgeon grasping the grasping portion of the endoscope and pressing the switch  77 , voltage is applied to the electromagnetic brakes  71 ,  72 , and  73  increasing by dE (V/sec). Accordingly, the fixation state is gradually disengaged.  
         [0186]    Then, when the surgeon releases the switch  77 , the control circuit  70  immediately shuts off electric power supply to the electromagnetic brakes  71 ,  72 , and  73 . Subsequently, the voltage is decreased by dEs (V/sec) per time increment.  
         [0187]    In other words, with the control circuit  70 , the electromagnetic brakes gradually operate to disengage the fixing force thereof in the event that the surgeon presses the switch  77  to move the endoscope  1 , due to the setting of the relation dE≦dEs between the amount of voltage increase and the amount of voltage decrease. Thus, the same operations and advantages as with the above embodiments can be obtained.  
         [0188]    Accordingly, with the present embodiment, the desired operations and advantages can be easily realized by adding this control circuit to the surgery equipment holding device using known electromagnetic brakes.  
         [0189]    Also, situations wherein force of the hand of the surgeon is suddenly applied to the surgery equipment holding device at the time of disengaging braking, which may occur even with balanced surgery equipment holding devices, can be avoided with the present embodiment, meaning that the surgeon can perform fixation disengaging operation of the surgery equipment without losing sight of the part to be treated or observed with the surgery equipment, and also can quickly perform fixing operations, as well.  
         [0190]    Now, FIG. 15 is a diagram explaining a modification of the fifth embodiment. As shown in FIG. 15, with the present embodiment, motor brakes  90  are used instead of the electromagnetic brakes  71 ,  72 , and  73  in the fifth embodiment.  
         [0191]    The motor brakes denoted by reference numeral  90  in the figure are motor brakes using known motors, and in the present embodiment the motor brakes  90  are disposed instead of the electromagnetic brakes  71 ,  72 , and  73  in FIG. 13.  
         [0192]    Here, description will be made regarding the motor brake  90  disposed at a lock of a swinging rod  81 , and description of the remaining motor brakes will be omitted since the configuration thereof is the same.  
         [0193]    A cover  80  is rotatably disposed so as to rotate on a rotating axis O 2  as the axis thereof, by bearings  91   a  and  91   b  disposed on a supporting member  79  disposed on the upper part of a vertical rod  82 . The lower end of the swinging rod  81  is linked to the cover  80 .  
         [0194]    Reference numeral  92  denotes a motor, which is electrically connected to the switch  77  via the control circuit  70 . The motor  92  is integrally fixed to an internal tube  94  by a screw  93 . Also, the internal tube  94  and the supporting member  79  are integrally fixed by a screw  95 .  
         [0195]    An operating screw  97  is rotatably disposed by bearings  96   a  and  96   b  within an internal tube  94 . This operating screw  97  is integrally joined to a rotational output shaft  92   a  of the motor  92 .  
         [0196]    At the time of disengaging fixation, the control circuit  70  runs the motor  92  at a rotation speed R (rpm), and at the time of fixing, runs the motor  92  at a rotation speed Rs (rpm). The present embodiment sets the relation of R&lt;&lt;Rs between the rotation speed R and the rotation speed Rs, thereby effecting control.  
         [0197]    Also, reference numeral  98  denotes a lock nut, wherein female threads for screwing the operating screw  97  to are formed on the inner face of the lock nut  98 , and a spline  98   a  is formed on the perimeter face thereof.  
         [0198]    A spline  79   a  capable of sliding with the spline  98   a  is formed on the end of the internal circumference of the supporting member  79  at the cover  80  side. Thus, rotation of the lock nut  98  in the direction of rotating around the rotational axis O 2  is suppressed, while being slidable parallel to the rotational axis O 2 .  
         [0199]    Reference numeral  98   b  denotes a pressing portion for pressing the internal face of the cover  80 , that has been formed on the end of the lock nut  98 .  
         [0200]    Now, the operation of the surgery equipment holding device will be described, including the operations of the motor brake.  
         [0201]    In the state that the cover  80  and the supporting member  79  are pressed and fixed by the pressing portion  98   b  formed on the end of the lock nut  98 , the surgeon pressing the switch  77  causes the control circuit  70  to run the motor  92 . The resultant rotating action of the rotating output shaft  92   a  starts rotation of the operating screw  97  which has been joined to the rotating output shaft  92   a  and is screwed to the lock nut  98 .  
         [0202]    At this time, the rotation of the lock nut  98  is suppressed by the spline  98   a  and  79   a.  Accordingly, the lock nut  98  moves parallel to the rotational axis O 2  in the direction of the arrow, and disengages the pressed state by the pressing portion  98   b . As a result, the cover  80  and the supporting member  79  become rotatable on the rotational axis O 2 .  
         [0203]    Subsequently, in the event that the surgeon releases the switch  77 , the control circuit  70  starts the motor  92  rotating in the direction opposite to that described above. Accordingly, action opposite to that described above causes the lock nut  98  to move parallel to the rotational axis  02  in the direction opposite to that described above, so that the pressing portion  98   b  is in the pressing state again, and the cover  80  and the supporting member  79  are in the fixing state again.  
         [0204]    Now, the rotation of the motor  92  is made by the control circuit  70  to be slower when fixation is disengaged as compared to when fixed, so the action of disengaging the surgery equipment that is held can be carried out gradually, while the fixing action can be performed rapidly, so the surgeon can work without losing sight of the part to be treated or observed with the surgery equipment  
         [0205]    In this way, according to the present configuration, the control of the fixing force is control of only the rotation speed of the motor, so electrical control can be performed even more easily.  
         [0206]    Having described the preferred embodiments of the invention referring to the accompanying drawings, it should be understood that the present invention is not limited to those precise embodiments and various changes and modifications thereof could be made by one skilled in the art without departing from the spirit or scope of the invention as defined in the appended claims.