Abstract:
A water feeding device for an endoscope, comprises: a first water feeding pipe line connected to an in-endoscope water feeding pipe line that feeds liquid into an object under observation; a second water feeding pipe line that is introduced into the object under observation through a treatment instrument insertion channel of the endoscope and supplies liquid; a water feeding pump portion that supplies liquid stored in a storage portion by a pump; and a pipe line switching section that selectively supplies the liquid stocked in the storage portion to the first and second water feeding pipe lines.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     The present invention relates to a water feeding device for an endoscope, and particularly to a water feeding device for an endoscope for supplying liquid into an object under observation by using a dedicated water feeding pipeline disposed in the endoscope and each kind of water feeding pipe line used through a treatment instrument insertion channel or a water feeding pipe provided to the treatment instrument.  
         [0003]     2. Description of the Related Art  
         [0004]     In the related-art endoscope device, a dedicated water feeding pipe line (so-called water jet pipe) is provided in an endoscope (scope), and cleaning physiological saline or drug solution for medical treatments is supplied to an object under observation (diseased part or the like) by a water feeding pump portion. The water feeding pipe is disposed separately from an air-feeding/water-feeding pipe line for cleaning an observation window of an object optical system.  
         [0005]     The endoscope device is provided with a treatment instrument insertion channel through which various kinds of treatment instruments are introduced, and liquid corresponding to the condition of an object under observation, the difference in treatment or the like is injected directly into the treatment instrument insertion channel, or a water feeding tube having each diameter is inserted into the treatment instrument insertion channel and then the liquid is injected into the water feeding tube. According to this endoscope device, a water feeding tube having a different diameter from that of the water jet pipe is used, and thus there is an advantage that the water feeding range (the breadth of the water feeding port), the water feeding amount or the water feeding speed can be selected in connection with the situation.  
         [0006]     A treatment instrument having a water feeding pipe line has been recently used. For example, with respect to a high-frequency knife for ablating a living tissue by high-frequency incision, cleaning water such as physiological saline or the like is fed from an affixed water feeding pipe line during cautery incision to clean a blood-issued part or the like.  
       SUMMARY OF THE INVENTION  
       [0007]     It is structurally vain that a water feeding pump portion (water feeding device) for supplying liquid is disposed for each of the dedicated in-endoscope water feeding (water jet) pipe line and the water feeding pipes used while inserted through the treatment instrument insertion channel. Therefore, according to the related-art endoscope devices, each of these pipe line and pipes is used while connected to the connection pipe of one water feeding pump portion. However, there is a problem that it is cumbersome to carry out a replacing work (i.e., connection replacement) between the water jet pipe and each water feeding pipe using the treatment instrument insertion channel, and thus there is a disadvantage that a wasting time must be consumed to carry out the connection replacement work during an observation or treatment work using the endoscope (e.g. see JP-A-2002-177208 and JP-A-2001-321332).  
         [0008]     Furthermore, in the related-art endoscope devices, a soft tube such as a silicon tube or the like is used for the water feeding connection pipe for connecting the water jet pipe and the water feeding pump portion, and thus there is a problem that there occurs a phenomenon (so-called creep) that residual water in the tube is fed even after a water feeding switch is stopped. That is, when the flow rate is increased (the flow amount is increased) toward the jet orifice of the water feeding pipe (a jet port in the case of the water jet pipe), the soft tube is expanded by the pressure of the fed water, and liquid existing in the expanded portion of the tube flows out after the water feeding operation is stopped.  
         [0009]     The present invention has been implemented in view of the foregoing problem, and has an object to provide a water feeding device for an endoscope in which it is unnecessary to carry out the replacing work (connection replacement) between a dedicated water feeding pipe line and a water feeding pipe line using a treatment instrument insertion channel, so that observation and treatments based on the endoscope can be rapidly performed, and also no residual water flows out after water feeding is stopped.  
         [0010]     In order to attain the above object, according to a first aspect of the invention, a water feeding device for an endoscope, comprises: a first water feeding pipe line connected to an in-endoscope water feeding pipe line that feeds liquid into an object under observation; a second water feeding pipe line that is introduced into the object under observation through a treatment instrument insertion channel of the endoscope and supplies liquid; a water feeding pump portion that supplies liquid stored in a storage portion by a pump; and a pipe line switching section that selectively supplies the liquid stocked in the storage portion to the first and second water feeding pipe lines.  
         [0011]     According to a second aspect of the invention, in the first aspect of the invention, the pipe line switching section comprises a change-over valve that switches the first water feeding pipe line and the second water feeding pipe line, the change-over valve being disposed between the water feeding pump portion and the first and second water feeding pipe lines.  
         [0012]     According to a third aspect of the invention, in the first aspect of the invention, the pipe line switching section comprises a first-pump for the first water feeding pipe line and a second pump for the second water feeding pipe line, the first and second pump being provided in the water feeding pump portion, and the first and second pumps are operable to be switched to each other.  
         [0013]     According to a fourth aspect of the invention, in the second aspect of the invention, the water feeding device further comprises a connecting pipe that connects the water feeding pump portion and the change-over valve, wherein each of the connecting pipe and the first water feeding pipe line comprises a hard synthetic resin pipe.  
         [0014]     According to the second aspect of the invention, the first water feeding pipe line and the second water feeding pipe line are switched to each other by the change-over valve such as a three-way turncock or the like, for example, and water feeding can be executed on a desired water feeding pipeline without replacing each water feeding pipe line to another pipe line.  
         [0015]     According to the third aspect of the invention, the first water feeding pipe line is connected to the pump for the first water feeding pipe line, and the second water feeding pipe line is connected to the pump for the second water feeding pipe line, and these pumps are selectively operated by a foot switch or the like, whereby water feeding can be carried out on a desired water feeding pipe line.  
         [0016]     According to the fourth aspect of the invention, the connecting pipe for connecting the water feeding pump portion and the change-over valve and the first water feeding pipe line are formed of hard synthetic resin pipes, and thus even when relatively high water feeding pressure is applied, these pipes are not expanded and no residual water flows out after the water feeding is stopped.  
         [0017]     According to the water feeding device for the endoscope of any of the first to fourth aspects of the present invention, it is unnecessary to carry out the replacing work (the connection replacement work) between the dedicated water feeding pipe line (water jet pipe) and the water feeding pipeline using the treatment instrument insertion channel, and the observation and treatment using the endoscope can be rapidly performed. Furthermore, by using the hard synthetic resin pipe, flow-out of residual water after water feeding is stopped can be prevented.  
         [0018]     Also, when there is used a dedicated in-endoscope water feeding (water jet) pipe line or a water feeding pipe used while inserted through the treatment instrument channel is used, dust or materials or the like of the object under observation clogs at the injection port of the water feeding pipe or a synthetic resin tube between the endoscope and the water feeding pump portion may be trodden in some cases. In such a case, the water feeding pressure in the pipe increases abnormally, and thus there occurs a disadvantage that the various kinds of water feeding pipes containing the water jet pipe are damaged or the water feeding tube is detached at the connection portion.  
         [0019]     Recently, not only the water jet pipe, but also various kinds of water feeding pipes using the treatment instrument insertion channels have been used, and thus the constructions of the pipe lines have been complicated. Furthermore, the water feeding conditions of the flow rate, the pressure, etc. have been complicated, and thus the probability that the above disadvantage occurs has been higher and higher.  
         [0020]     The present invention has been implemented in view of the foregoing problem, and has an object to provide a water feeding device for an endoscope in which the water feeding pressure in a pipe can be prevented from increasing abnormally, and damage of water feeding pipes such as a water jet pipe, etc. and detachment of a water feeding tube at a connection portion can be prevented.  
         [0021]     In order to attain the above object, according to a fifth aspect of the invention, a water feeding device for an endoscope, comprises: a water feeding pump portion that supplies liquid in a storage portion by a pump; a water feeding pipe line that is disposed so as to pass from the water feeding pump portion through the endoscope and supplies liquid to an object under observation; and one of an orifice and an automatic opening/closing type pressure relief valve, that limits the maximum water feeding pressure (the pressure of fluid in a pipe line) and is provided to a water feeding pipe line disposed between the water feeding pump portion and the endoscope.  
         [0022]     According to a sixth aspect of the invention, in the fifth aspect of the invention, at least one of a first water feeding pipe line connected to the water feeding pipe line in the endoscope and a second water feeding pipe line to be introduced through a treatment instrument insertion channel of the endoscope is connected to the water feeding pump portion, and said one of the orifice and the automatic opening/closing type pressure relief valve is provided to an output port pipe connected to said at least one of the first and second water feeding pipe.  
         [0023]     According to a seventh aspect of the invention, in the fifth aspect of the invention, the water feeding device for the endoscope further comprises a pipe line that returns liquid flowing out from said one of the orifice and the automatic opening/closing type pressure relief valve to the storage portion, the pipe line being provided between: one of the orifice and the pressure relief valve; and the storage portion.  
         [0024]     According to the fifth to seventh aspects of the present invention, when the pressure in the water feeding pipe line is equal to or more than the maximum water feeding pressure set by the orifice or pressure relief valve, the liquid flows out from the orifice or pressure relief valve, so that the pressure equal to or higher than the maximum water feeding pressure can be prevented from being applied to the water feeding pipe line.  
         [0025]     According to the construction of the seventh aspect of the invention, the liquid flowing out from the orifice or pressure relief valve is returned to the storage portion by the return pipe line (feedback path), and thus the liquid is re-used.  
         [0026]     According to the fifth to seventh aspect of the water feeding device for the endoscope of the present invention, since the water feeding pressure does not abnormally increase, the water jet pipe or each kind of water feeding pipe used while inserted through the treatment instrument insertion channel is neither damaged-nor broken, and the water feeding tube is prevented from being detached at the connection portion, so that excellent use of the observation and the treatment can be secured.  
         [0027]     Liquid such as physiological saline, drug solution or the like to be fed to an object under observation is stocked in a storage tank, and the liquid in the tank is fed to the object under observation through a water feeding device and a water feeding pipe in an endoscope. Sanitary supervision is required to the tank and the liquid in the tank. Furthermore, in the examination and treatment using an endoscope, liquid in the same tank is frequently used for plural persons being tested, patients, and in such a case a system mechanism for preventing backflow of liquid from a water feeding pipe at the endoscope side into the tank is required from the viewpoint of hygiene, bacterial infection, etc.  
         [0028]     Furthermore, in the examination and treatment using the endoscope, drug solution such as antifoaming agent or the like is injected to liquid such as physiological saline or the like as occasion demands, and it is also required to facilitate proper injection of drug solution as described above. Furthermore, the related-art liquid tank  1  is designed so that a take-out pipe  2  is disposed so as to extend from a cap  1   a  to the lower side as shown in  FIG. 15 , and liquid is sucked up from the take-out pipe  2 . Therefore, stocked liquid  100  remains at the lower portion, and all the liquid in the tank  1  is not perfectly used.  
         [0029]     The present invention has been implemented in view of the foregoing problem and has an object to provide a water feeding device for an endoscope that enables a disposable container dedicated to the same patient and thus can keep the container under a high sanitary state, and also that can facilitate proper injection of drug solution and further enable all the liquid in a container to be perfectly used.  
         [0030]     In order to attain the above object, according to an eight aspect of the invention, in the first or fifth aspect of the invention, the storage portion comprises a liquid container, the liquid container comprising: a liquid container comprising (i) a fitting member that is fitted to and suspended by a suspending member, (ii) a main body that stocks liquid and (iii) a rubber liquid take-out portion that is disposed at a lower portion of the main body and through which an injection needle penetrates, and the water feeding device further comprises a connection pipe line that is connected to the water feeding pump portion and to which the injection needle is secured, and liquid is fed from the liquid container to the water feeding pump portion under the state that the liquid container is suspended by the suspending member and the injection needle is stung.  
         [0031]     According to a ninth aspect of the invention, the connection pipe line to which the injection needle is secured comprises a connector (for example, Luer lock connection type connector) that selectively connecting the injection needle and a take-out pipe line equipped to a tank.  
         [0032]     According to an eight aspect of the present invention, a liquid bag (pack) using a synthetic resin soft bag-can be used as the liquid container as in the case of the related-art fluid infusion (blood infusion). The liquid container is suspended by the suspending member, and the injection needle is stung into the rubber liquid take-out portion at the lower portion of the liquid container, whereby liquid in the liquid container is supplied through the connection pipe line to the water feeding pump portion, and the liquid is fed from the water feeding pump portion through the water feeding pipe line in the endoscope into the object under observation. At this time, a syringe needle in which drug solution is filled may be stung into the rubber liquid take-out portion to add the drug solution to the liquid.  
         [0033]     According to the ninth aspect of the invention, the injection needle and the take-out pipe of the related-art tank can be exchanged by a Luer lock connection type connector, for example, and each of the liquid bag of the present invention and the tank equipped with the take-out pipe line can be selected as occasion demands.  
         [0034]     According to the endoscope of the eighth or ninth aspect of the invention, the liquid bag or the like can be used as a container which can be used only once (single use) dedicated to the same patient, and a high sanitary state can be secured. Furthermore, drug solution to be added to liquid fed into the object under observation can be easily properly injected, and further all the liquid in the container can be perfectly used with no residual. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0035]      FIG. 1  is a diagram showing the construction when the water feeding device for an endoscope according to the embodiment 1-1 of the present invention is applied;  
         [0036]      FIGS. 2A and 2B  is a diagram showing the change-over operation of a change-over valve according to the embodiment 1-1;  
         [0037]      FIG. 3  is a diagram showing the construction when a water feeding device for an endoscope according to the embodiment 1-2 is applied to an endoscope;  
         [0038]      FIG. 4  is a diagram showing the detailed construction of the water feeding device for the endoscope according to the embodiment 1-2;  
         [0039]      FIG. 5  is a perspective view showing the construction of a water feeding pump portion and a tank according to the device of the embodiment 1-1;  
         [0040]      FIG. 6  is a diagram showing the construction when the water feeding pup portion and the tank of the embodiment 1-1 are arranged in a system rack;  
         [0041]      FIG. 7  is a diagram showing the relationship between the operation of a foot switch [(A)] and a water feeding amount [(B)] of a water jet for the water feeding according to the embodiment 1;  
         [0042]      FIG. 8  is a partially cross-sectional view showing the construction of the tank of the embodiment 1;  
         [0043]      FIG. 9  is a diagram showing the construction of a water feeding device for an endoscope according to the embodiment 2 of the present invention;  
         [0044]      FIG. 10A  shows a cross-sectional view of an orifice of the embodiment 2;  
         [0045]      FIG. 10B  shows a diagram when viewed from the inside of the pipe line on the orifice of the embodiment 2;  
         [0046]      FIG. 11  is a diagram showing the construction of a pump and the construction of a circuit for flow rate adjusting control in the embodiment 2;  
         [0047]      FIG. 12  is a diagram showing the construction of a pressure relief valve arranged in the device of the embodiment 2;  
         [0048]      FIG. 13  is a diagram showing the construction of a water feeding device for an endoscope according to the embodiment 3 of the invention;  
         [0049]      FIG. 14  is a diagram showing another construction of the liquid container of the embodiment 3; and  
         [0050]      FIG. 15  is a diagram showing the construction of the related-art liquid tank. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
     Embodiment 1  
       [0051]      FIGS. 1 and 2  show the construction of a water feeding device for an endoscope according to an embodiment 1-1. As shown in  FIG. 1 , an endoscope (electronic endoscope)  10  has an insertion portion  10 A, an operating portion  10 B and a cable portion  10 C, and it is connected to a light source device  13  shown in  FIG. 1  by a connector  12  of the cable  10 C. In the case of the electronic endoscope, the cable  10 C is also connected to a processor device. Various kinds of pipe lines are provided in the endoscope  10 . A water jet pipe (dedicated water feeding pipe line)  15   a  is disposed so as to extend from the tip of the insertion portion  10 A to the rear end portion of the operating portion  10 B. An air-feeding/water-feeding pipe  16   a  is provided at the tip side to clean an observation window (lens face) of an object optical system equipped to the tip of the insertion portion  10 A through a nozzle, and an air-feeding pipe  16   b  and a water feeing pipe  16   c  are provided so as to intercommunicate with the air-feeding/water-feeding pipe  16   a.    
         [0052]     The endoscope  10  is equipped with a treatment instrument insertion channel  17   a  which also serves as a suction pipe, and a suction pipe  17   b  intercommunicating with the treatment instrument insertion channel  17   a , and the treatment instrument insertion channel  17   a  is provided with a forceps port (treatment instrument insertion port)  20  is provided at the position corresponding to the operating portion  10 B. A second water feeding pipe  18  is inserted from the forceps port  20  into the treatment instrument channel  17   a , and water feeding tubes formed of hard synthetic resin and having various diameters and water feeding pipes provided for treatment instruments such as a high-frequency knife, etc. exist as the second water feeding pipe  18 .  
         [0053]     An air-feeding/water-feeding operation valve (switch)  22  is provided at some midpoint in the air-feeding pipe  16   b  and the water-feeding pipe  16   c  for cleaning the observation window described above, and a tank (first water feeding tank)  23  is connected to the air-feeding pipe  16   b  and the water-feeding pipe  16   c . The air-feeding pipe  16   b  is connected through the connection pipe  16   d  to a pump  24  inside (separately from) the light source  13 , and air feeding and water feeding to the observation window are carried out by a two-step pushing operation of the air-feeding/water-feeding operation valve  22 , for example. Furthermore, the suction pipe  17   b  is provided with a suction operation valve (switch)  27  at some midpoint thereof, and it is connected to a suction device through the connection pipe of the connector  12 . By operating the suction operation valve  27 , contents in the object under observation can be sucked (through  17   a ,  17   b ) and discharged.  
         [0054]     The water feeding device for the endoscope is equipped with a water feeding pump portion  30  for feeding liquid into the object under observation, and the water feeding pump portion  30  is quipped with a pump portion main body  31  having a motor and a control circuit, a pump  32  disposed at the front side of the main body  31 , a foot switch  33  for carrying out a water feeding operation and a tank (second water feeding tank)  34 . The tank  34  is connected to the pump  32  (input port) through the connection pipe  15   d . The pump  32  is designed so that a soft water feeding tube is disposed circumferentially on outer periphery of a rotor, a pressing member which rotationally moves while crushing the tube is secured on the outer periphery of the rotor, and liquid in the tube is pushed out by rotating the rotor, thereby feeding water.  
         [0055]     In this embodiment, the first water feeding pipe  15   b  and the connection pipe  15   c  are provided to connect the pump  32  (the output part) and the water jet pipe  15   a  disposed in the endoscope  10 , and the pipe line change-over valve  36  (1 input and 2 outputs) comprising the three-way turncock, a choke valve, etc. is provided between the first water feeding pipe  15   b  and the connection pipe  15   c . The connection pipe  15   c  at the pump  32  side is connected to the one input of the change-over valve  36 , and the first water feeding pipe  15   b  and the second water feeding pipe  18  are connected to the two outputs of the change-over valve  36 . That is, according to this embodiment, the water feeding operation using the water jet pipe  15   a  in the endoscope and the water feeding operation using the second water feeding pipe  18  corresponding to each water feeding tube having each diameter or a water feeding pipe provided to a treatment instrument such as a high-frequency knife or the like, which is introduced from a forceps port  20  through a treatment instrument insertion channel  17   a  into an object under observation are selectively switched to each other and used by manually operating the change-over valve  36 .  
         [0056]      FIG. 2  shows the operation state of the change-over valve  36 , wherein  FIG. 2 (A) shows a state that the connection pipe  15   c  at the pump  32  side and the first water feeding pipe  15   b  are connected to each other (the pipes are opened) by operating the lever of the change-over valve  36  (the second water feeding pipe  18  is closed), and when the lever is counterclockwise turned from this state by 90 degrees, the connection pipe  15   c  at the pump  32  side and the second water feeding pipe  18  are connected to each other (the first water feeding pipe  15   b  is closed).  
         [0057]     According to the-embodiment 1-1 as described above, any one of the water feeding operation using the water jet pipe  15   a  (first water feeding pipe  15   b ) provided in the endoscope and the water feeding operation using the second water feeding pipe  18  comprising each water feeding tube having each diameter or the water feeding pipe provided to the treatment instrument such as the high-frequency knife or the like which is introduced from the forceps port  20  through the treatment instrument insertion channel  16   a  into the object under observation can be selected by manually operating the mechanical change-over valve  36 , and the water feeding operation under various conditions can be executed in accordance with the observation/treatment condition. The water feeding operation can be carried out on both the pipes  15   a  and  18  by operating the change-over valve  36 .  
         [0058]      FIGS. 3 and 4  shows the construction of a water feeding device for an endoscope according to an embodiment 1-2. In this second embodiment, a pump for a first water feeding pipe line and a second water feeding pipeline are provided. As shown in  FIGS. 3 and 4 , the pump portion main body  39  is equipped with a first pump  32 A and a second pump  32 B. The first water feeding pipe  15   b  is connected to the output port of the first pump  32 A, and the second water feeding pipe  18  is connected to the output port of the second pump  32 B. A tank  34  is connected to the input ports of the first and second pumps  32 A,  32 B by a connection pipe  15   e.    
         [0059]     Furthermore, as shown in  FIG. 4 , pump driving circuits  39   a ,  39   b  containing motors for driving the first and second pups  32 A,  32 B, and a control circuit  39   c  for receiving a signal from a foot switch  40  serving as a water feeding operation switch and controlling the switching operation between the two pump driving circuits  39   a  and  39   b  are provided in the pump portion main body  39 . The foot switch  40  comprises a two-step push switch. The control circuit  39   c  drives the first pump  32 A by one-step push, and also drives the second pump  32 B by two-step push. Two foot switches  33  having the same construction as the embodiment 1-1 may be arranged as the water feeding operating switch in connection with the two pumps  32 A,  32 B  
         [0060]     According to the embodiment 1-2 as described above, one of the first pump  32 A and the second pump  32 B is operated by operating the foot switch  40 , and any one of the water feeding operation using the water jet pipe  15   a  (and the first water deeding pipe  15   b ) and the water feeding operation using the second water feeding pipe  18  which is inserted through the treatment instrument insertion channel  17   a  and corresponds to the water feeding tube of each diameter or the water feeding pipe provided to the treatment instrument such as a high-frequency knife or the like can be selected, and the water feeding under each condition corresponding to the observation/treatment condition can be executed. Both the pumps  32 A and  32 B can be operated.  
         [0061]     FIGS.  5  to  8  show the specific construction of the water feeding pump portion and the tank in the embodiment 1-1 (which is also applicable to the embodiment 1-2). As shown in  FIGS. 5 and 6 , the main body  31  of the water feeding pump portion (device)  30  is equipped with a power supply switch  44 , a connecting portion  45  of the foot switch  33 , etc. Furthermore, the connection pipe  15   d  at the tank side is connected to the input port  46  of the pump  32 , and the connection pipe  15   c  at the endoscope side is connected to the output port  47  of the pump  32 . In this embodiment, the connection pipe  15   c  (water feeding output side) and the first water feeding pipe  15   b  connected to the water jet pipe  15   a  and the first water feeding pipe  15   b  connected to the water jet pipe  15   a  are formed of hard synthetic resin pipes, for examples, pipes formed of materials such as Teflon (registered trademark), polytetrafluoroethylene (fluorocarbon resin) or the like, which are never deformed or little deformed even when the water feeding pressure is high. The second water feeding pipe  18  is also likewise formed of a synthetic resin pipe.  
         [0062]     According to the connection pipe  15   c  and the first water feeding pipe  15   b  which are formed of such hard synthetic resin pipes, after the water feeding operation is stopped by the foot switch  33 , the residual water in the pipes is prevented from flowing out from the outlet of the water jet pipe  15   a  at the tip of the endoscope.  FIG. 7  shows the relationship between the operation of the foot switch  33  of this embodiment and the water feeding amount from the outlet of the water jet pipe  15   a . In the related-art endoscope in which a soft synthetic resin pipe such as a silicon tube or the like is used for the connection pipe ( 15   c ), even when the foot switch  33  is set to off [(A) of  FIG. 7 ], the expanded soft synthetic resin pipe is contracted, so that the water feeding of the residual water in the pipe continues until a finish time t 1  (from several seconds to eight seconds, for example) as indicated by a dotted line of (B) of  FIG. 7 . However, according to the hard synthetic resin connection pipe  15   c  of this embodiment, even after the foot switch  33  is set to off, the water feeding of the residual water is immediately finished at a finish time t 2  (within one second) as indicated by a solid line of (B) of  FIG. 7 , so that the creep phenomenon can be greatly improved.  
         [0063]     In  FIGS. 5 and 6 , the connection pipe  15   d  connected to the input port  46  of the pump  32  is designed to be bifurcated through a pipe line change-over valve (three-way turncock or the like, 2 inputs, 1 output)  49 . (Liquid) take-out pipes  53  of two tanks  34  are connected to the bifurcated connection pipe  15   d  through Luer-locks  50  serving as rotational spiral coupling type connectors. Accordingly, in this embodiment, when all the liquid in one of the tanks  34  is consumed, the liquid in the other tank  34  may be used by switching the input pipe line of the change-over valve  49 . During use of one of the tanks  34 , the other tank  34  may be supplemented with liquid or exchanged by a new tank  34 .  
         [0064]     Furthermore, the tank  34  is formed so as to have a capacity of 1000 ml or more. That is, the tank capacity of the prior art is set to about 500 ml. Since liquid of 200 to 300 ml or more is used for each case to clean mucous membrane, etc. of a site under observation in the observation and treatment using the endoscope, and thus there has frequently occurred such a case that the tank does not satisfy the liquid amount necessary for three cases. However, this embodiment has a capacity of 1000 ml or more, and thus the liquid amount required for four cases or more can be secured.  
         [0065]     Furthermore, as shown in  FIG. 6 , the tank  34  is designed so that the height thereof is set to be substantially equal to or less than the height H 1  of the pump portion main body (housing)  31 , whereby the arrangement of the parts mounted in a system rack or the like can be efficiently performed. That is, in the endoscope device, not only the endoscope (scope), but also various devices such as a processor device, a light source device, a recording device, a pump for feeding air and water to the observation window, a tank, etc. are provided, and it is required to mount these devices in a system rack having a multiple-step accommodating space or the like. Therefore, according to this embodiment, the height of the tank  34  is set to be substantially equal to (or lower than) the pump portion main body  31  as shown in  FIG. 6 , whereby these parts are efficiently accommodated in the accommodating space surrounded by the partition plate  155  of the system rack or the like.  
         [0066]      FIG. 8  shows the construction of a liquid take-out amount (outlet pipe) of the tank  34 . According to the tank  34  of this embodiment, the liquid take-out pipe is not formed so as to extend from the cap  34   a  as shown like the prior art (as shown in the tank  23  of  FIG. 1 ), but it is formed along the side surface of the tank so that a part of the take-out pipe  53  is formed integrally from the upper portion to the bottom surface of the tank, and a pipe port  53 E is provided to the bottom surface portion of the tank. According to this construction, the take-out pipe  53  does not affect the height of the tank  34 . Accordingly, as compared with a case where the take-out pipe  53  is disposed in the cap  34   a , the position of the upper end of the cap  34   a  can be set to the height H 1  of the pump portion main body  31 , and thus the tank capacity when the height of the tank  34  is set to be substantially equal to the height of the pump portion main body  31  can be achieved, so that this embodiment is effective to even a case where the capacity is set to 1000 ml or more.  
       Embodiment 2  
       [0067]     The overall construction of the water feeding device for an endoscope according to the embodiment 2 is same as in the embodiment 1 (See  FIG. 1 ).  
         [0068]      FIG. 9  shows the detailed construction of the water feeding pump portion  30  and the tank  34  on the embodiment 2. As shown in  FIG. 1 , a power supply switch  44 , a connection portion  45  of a foot switch  33 , etc. are provided in the main body  31  of the water feeding pump portion (device)  30 . In addition, the connection pipe  15   d  at the tank side is connected to the input port pipe  46  of the pump  32 , and a liquid take-out pipe  53  of the tank  34  is connected to the connection pipe  15   d  through a Luer lock  50 . The connection pipe  15   c  to be connected to the endoscope side is connected to the output port pipe  47  of the pump  32 .  
         [0069]     In the embodiment 2, an orifice  55  for setting the maximum water feeding pressure in the pipe is provided to the output port pipe  47  of the pump  32 .  FIGS. 10A and 10B  show the construction of the orifice  55 . The output port pipe  47  is formed of a hard synthetic resin pipe, and the orifice (hole, opening)  55  comprising a hole of a mm in diameter is formed in the side surface of the synthetic resin pipe. The diameter a of the orifice  55  is set in consideration of the hardness of the synthetic resin pipe of the output port  47  so that prescribed pressure of 29.4 Pascal or less is the maximum water feeding pressure. According to this orifice  55 , when the pressure in the water feeding pipe ( 15   a  to  15   c ,  18 ) is equal to the predetermined maximum water feeding pressure or more, the liquid in the pipe is made to flow out to the outside, whereby the in-pipe pressure can be kept to be less than the maximum water feeding pressure. The orifice  55  may be formed, not in the output port pipe  47 , but at some midpoint of the connection pipe  15   c , the first water feeding pipe  15   b  or the second water feeding pipe  18  or the connection portion thereof or the like.  
         [0070]     According to the embodiment 2, as shown in  FIG. 9 , a check valve  57  is provided at some midpoint of the connection pipe  15   c , and also a return pipe  58  for returning fluid to the tank  34  is secured between the orifice  55  and the tank  34 . That is, when the pressure in the water feeding pipe becomes the maximum water feeding pressure or more, the liquid which flows out from the orifice  55  between the check valve  57  and the pump side is returned to the tank  34  and re-used.  
         [0071]     An orifice having a predetermined diameter may be formed as the orifice  55  by crushing a soft synthetic resin tube with a pinch valve or the like. In this case, the tube itself constituting the orifice is set as the return pipe  58 , or the tube is connected to the return pipe  58 .  
         [0072]     According to the construction of the embodiment 2, the water jet pipe  15   a  and the second water feeding pipe  18  inserted from the forceps port  20  through the treatment instrument insertion channel  17   a  are switched to each other by the change-over valve  36 , and target liquid can be fed into the object under observation through the selected water feeding pipe. At this time, when the in-pipe pressure of the water feeding pipe ( 15   a  to  15   c ,  18 ) is equal to the maximum water feeding pressure or more, the liquid is made to flow out to the external by the orifice  55 , whereby the in-pipe pressure can be kept to be less than the maximum water feeding pressure. Furthermore, the liquid flowing out from the orifice  55  is returned into the tank  34 , and re-used. At this time, the back flow of the liquid from the water feeding pipes  15   a  to  15   c ,  18  is suppressed by the check valve  57 . For example, liquid which is not kept under a good sanitary conditions is prevented from being returned from the endoscope side to the tank  34  and re-used.  
         [0073]     In the embodiment 2, as shown in  FIG. 9 , a flow rate adjusting finger grip (a variable-resistance finger grip)  60 F is provided to the front surface of the pump portion main body  31 . An arcuate graduated index is provided around of the flow rate adjusting finger grip  60 F, and the flow rate of water to be fed can be steplessly adjusted by the variable resistor ( 60 ).  
         [0074]      FIG. 11  shows the construction of the pump  32  and the construction of a circuit for flow rate adjusting control. As shown in  FIG. 4 , in the pump  32 , plural press members  63   b  are provided around the outer periphery of a rotor  63  whose rotational shaft  63   a  is secured to the driving shaft of a DC motor  62 , and a soft water feeding tube  64  are circumferentially arranged on the outer periphery of the rotor  63 . The press members  63   b  of the rotor  63  rotates while crushing the water feeding tube  64 , and pushes out liquid, thereby carrying out water feeding. To the motor  62  are connected a DC power source  65  and a variable resistor (volume)  60  for controlling the power (current) of the power source  65 . The variable resistor  60  is designed to be operable by the flow rate adjusting finger grip  60 F.  
         [0075]     According to the variable resistor  60  having the flow rate adjusting finger grip  60 F, the rotational number of the motor  62  is controlled by controlling the power amount (current amount) supplied from the DC power source  65 , whereby the water feeding flow rate can be adjusted/controlled steplessly and continuously. As shown in  FIG. 9 , the arcuate flowrate graduating index is provided around the flow rate adjusting finger grip  60 F, and for example, the flow rate from the minimum flow rate (min) of 90 ml/sec till the maximum flow rate (max) of 200 ml/sec can be adjusted/set.  
         [0076]      FIG. 12  shows the construction of the pressure relief valve which can be utilized in place of the orifice  55 . As shown in  FIG. 5 , the pressure relief valve  67  is disposed at the connection portion of the return pipe  58  on the side surface of the output port pipe  47 . The pressure relief valve  67  has an opening/closing valve disc  67   a  and an urging member (spring or the like)  67   b  for moving the valve disc  67   a  forwardly and reversely, and the urging force of the urging member  67   b  is set so that the valve disc  67   a  is opened by the maximum water feeding pressure which is set to 29.4 k Pascal or less. In this case, when the maximum water feeding pressure becomes abnormal, the liquid is made to flow out to the outside by opening the valve disc  67   a , whereby the in-pipe pressure can be kept to be less than the maximum water feeding pressure. An elastic member formed of synthetic resin may be used for the urging member  67  and the elastic member may be formed integrally with the valve disc  67   a.    
       Embodiment 3  
       [0077]     The overall construction of the water feeding device for an endoscope according to the embodiment 3 is same as in the embodiment 1 (See  FIG. 1 ).  
         [0078]      FIG. 13  shows the detailed constructions of the water feeding pump portion  30 , the liquid bag and the tank  34  on the embodiment  3 . As shown in  FIG. 1 , the main body  31  of the water feeding pump portion (device)  30  is equipped with a power supply switch  44 , a connection portion  33 C of a foot switch  33 , a flow rate adjusting finger grip (variable resistor)  245 , etc. The connection pipe  15   d  at the tank side is connected to the input port pipe  46  of the pump  32 , and the connection pipe  15   c  at the endoscope side is connected to the output port pipe  47  of the pump  32 . A Luer connection type (male and female screw fixing type) female connector  50  is secured to the tip of the connection pipe  15   d , and a male screw portion of the injection needle  52  and the female connector  50  screw together.  
         [0079]     In the embodiment 3, a liquid bag  54  is provided as a liquid container. The liquid bag  54  has the same construction as a fluid infusion (blood infusion) bag, and it comprises a soft synthetic resin main body bag  54   a  for stocking liquid such as physiological saline, drug solution or the like therein, a fitting hole  54   b  that is disposed at the upper portion of the main body bag  54   a  and fitted to a suspending hook  56  disposed in a dedicated stand, a system rack of the endoscope or the like, and a rubber liquid take-out portion  54   c  disposed at the lower portion of the main body bag  54   a.    
         [0080]     In the tank  34  of the embodiment 3, the liquid take-out pipe  34 P is disposed so as not to extend from the cap, but to extend from the upper portion of the side surface along the tank side surface to the bottom portion, and the Luer lock connection type male connector  51  to be connected to the female connector  50  is provided to the tip of the take-out pipe  34 P.  
         [0081]     According to the construction described above, the fitting hole  54   b  is fitted to the suspending hook  56  of  FIG. 13  to suspend the liquid bag  54 , and the injection needle  52  connected to the female connector  250  of the connection pipe  15   d  is stung into the rubber liquid take-out portion  54   c  of the liquid bag  54 , whereby liquid such as physiological saline or the like in the liquid bag  54  can be supplied into the endoscope  10  side by the pump  32 . At this time, a syringe (injection syringe) in which drug solution is filled is connected to another injection needle  57  shown in the figure, and the injection needle  57  is stung into the rubber liquid take-out portion  54   c , whereby drug solution such as antifoaming agent or the like is properly added to the liquid and supplied from the water feeding pump portion  30 .  
         [0082]     In the embodiment 3, the water jet pipe  15   a  of  FIG. 1  and the second water feeding pipe  18  inserted from the forceps port  20  through the treatment instrument channel  16   a  can be switched to each other by the change-over valve  36 , and target liquid can be fed into the object under observation through the water feeding pipe selected in accordance with the condition.  
         [0083]     According to the liquid bag  54 , the liquid container can be set as a disposal (only-once usable) liquid container, and also no air exists in the container, so that all the liquid can be taken out from the injection needle  52  with no residual.  
         [0084]     Furthermore, according to the embodiment 3, after the injection needle  52  is detached from the Luer lock connection type female connector  50 , the male connector  51  of the take-out pipe  34 P of the tank  34  may be connected to the female connector  50  to use the liquid in the tank  34  as shown in  FIG. 13 . That is, the liquid bag  54  and the tank  34  having the take-out pipe  34 P can be selected in accordance with the situation.  
         [0085]      FIG. 14  shows another example of the liquid container according to the embodiment 3. In this example, a soft bag is not used, but a hard container is used. That is, the liquid container  58  comprises a main body container  58   a  formed of hard synthetic resin or glass container or the like, a mesh-type supporter  58   b  that has a fitting portion  58   b  at the upper portion thereof and wound around the outer periphery of the main body container  58   a  so as to hold the main body container  58   a , and a rubber liquid take-out portion  58   d.    
         [0086]     In the case of the above-described liquid container  58 , the liquid container  58  is also suspended by fitting the fitting portion  58   b  to the suspending hook  56 , the injection needle  52  connected to the connection pipe  15   d  is stung into the rubber liquid take-out portion  58   d  of the liquid container  58 , and also another injection needle  52  for securing an air supply passage is stung into the rubber liquid take-out portion  58   d , whereby the liquid such as physiological saline or the like in the liquid container  58  can be supplied to the endoscope  10  side by the pump  32 .  
         [0087]     The entire disclosure of each and every foreign patent application from which the benefit of foreign priority has been claimed in the present application is incorporated herein by reference, as if fully set forth.