Patent Publication Number: US-2022226621-A1

Title: Fluid pressure gun device for balloon catheter

Description:
CROSS-REFERENCE TO RELATED U.S. APPLICATIONS 
     Not applicable. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates generally to a pressure unit for balloon catheter, and more particularly to an innovative structure type of a fluid pressure gun device for a balloon catheter. 
     2. Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 37 CFR 1.98. 
     The balloon catheter is a soft catheter provided with an inflatable balloon at the top. In the angioplasty, the balloon catheter is usually used in blood vessels to widen narrow regions or make channels. When in use, the uninflated balloon is positioned, the balloon is inflated according to different surgical purposes, the balloon expands and pushes blood vessels open, the balloon catheter can be removed after the balloon is deflated. 
     It is known that a fluid injection device is used to inflate and deflate the balloon for the angioplasty inside the blood vessel, including a tubular main body, the front end of the main body is connected to a fluid tube, a chamber is formed inside the main body, the chamber communicates with the fluid tube, the fluid tube communicates with the balloon catheter through a connection fitting. The front end of the main body is provided with a pressure monitoring device for monitoring and indicating the pressure inside the chamber. A plunger is movably disposed in the chamber, the front end of the plunger is provided with a piston, the back end of the plunger extends out of the main body and has an operating part, the operating part is operated to make the plunger pull the piston to reciprocate inside the chamber, so as to inject fluid into or extract fluid from the balloon. A male thread is formed on the periphery of the plunger. One side of the plunger of the main body is provided with a screw structure, the screw structure has a female thread fitting the male thread, the screw structure can be optionally combined with or disengaged from the plunger by laterally pushing or pulling the screw structure. 
     In the initial stage when the balloon is injected with fluid to dilate the balloon, the screw structure is disengaged from the plunger, and the plunger and the piston can be moved forward rapidly. When the screw structure is laterally combined with the plunger, the plunger and the piston can push the fluid into the balloon while the shot volume is controlled accurately by turning the plunger. To make the fluid depart from the balloon to deflate the balloon, the screw structure is laterally disengaged from the plunger, the pressure of the balloon and the fluid pushes the piston, so that the piston and the plunger can move backward rapidly, the balloon is deflated rapidly. 
     The screw structure is combined with the plunger, the plunger can resist the pressure from the fluid, but the screw structure is only combined with the plunger on one side of the plunger, the plunger is partially stressed, said pressure may induce slight lateral deformation of the plunger in the direction far from the screw structure, the reliability of effective screwing of the female thread and the male thread is influenced. The female thread and the male thread have the risk of structural failure, and the plunger may be disengaged from the screw structure. 
     BRIEF SUMMARY OF THE INVENTION 
     The primary objective of the present invention is to provide a fluid pressure gun device for a balloon catheter. 
     Based on said objective, the technical characteristic of problem solving of the present invention is that the fluid pressure gun device for a balloon catheter includes a tubular cavity, a fluid tube, a pressure monitoring device, a plunger, a screw structure, a cover casing and a detent structure. A chamber is formed inside the cavity for storing fluid, and the front end of said cavity is connected to said fluid tube, Said chamber communicates with said fluid tube. Said fluid tube is provided with a connection fitting, so that the fluid tube communicates with a balloon catheter. Said pressure monitoring device is disposed in the cavity for monitoring and indicating the pressure of the fluid. Said plunger is movably disposed in said chamber. A piston is pivoted at the front end of said plunger, and said piston and said cavity are fitted closely, so that said plunger pulls the piston to reciprocate in said chamber to inject the fluid into or extract the fluid from the balloon of said balloon catheter. An operating part is formed at the back end of said plunger, facilitating the axial displacement or rotation of said plunger. Said screw structure is optionally combined with or disengaged from said plunger, so that said plunger resists the pressure from the fluid, and the displacement of said plunger and said piston is controlled. 
     Said cover casing is arranged at the back end of the cavity. A chamber is formed inside the cover casing. Said plunger protrudes out of the back end of the cover casing through said chamber, and said plunger is provided with a first screw thread structure. Said first screw thread structure is at least formed on opposite side of said plunger. 
     Said screw structure is disposed in said chamber. Said screw structure comprises two screw blocks, said screw blocks being oppositely arranged centering on said plunger said screw blocks form a second screw thread structure fitting sad first screw thread structure respectively, so that said screw blocks are screwed on said plunger. Said screw structure has several springs between said screw blocks and said cover casing. Said springs prop said screw block and said cover casing respectively, so as to provide thrust. The screwing reliability of said screw blocks and said plunger is enhanced. 
     Said detent structure comprises two cams, two arm levers and one connecting rod, wherein said cam is an elliptical disc, said cams are pivoted between said screw blocks respectively, and said cams are adjacent to both ends of said screw blocks far from said plunger respectively. A construction line is defined to pass through the center of said cams, and the construction line radially passes through said plunger. Said arm levers are connected to said cams respectively. Both ends of said connecting rod are connected to said arm levers respectively, so that said arm levers pull said cams to rotate synchronously to perform combination or disengagement of said second screw thread structure and said first screw thread structure. 
     In terms of the main effect and advantage of the present invention, the plunger is supported by the screw blocks at least on two opposite sides, the first screw thread structure and the second screw thread structure have high reliability of effective screwing. [ 0012 ]Another purpose of the present invention is to achieve the advantage and practical progressiveness of easy combination or disengagement of the screw blocks and the plunger based on the detent structure. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
         FIG. 1  is a stereogram ( 1 ) of the preferred embodiment of the present invention. 
         FIG. 2  is a top view of the preferred embodiment of the present invention in the state shown in  FIG. 1 . 
         FIG. 3  is a three-dimensional exploded diagram of the preferred embodiment of the present invention. 
         FIG. 4  is the  4 - 4  section view of  FIG. 2 . 
         FIG. 5  is the  5 - 5  section view of  FIG. 2 , showing the screw structure and plunger bonding state. 
         FIG. 6  is the  6 - 6  section view of  FIG. 2 , showing the state of cam pivoted between two screw blocks. 
         FIG. 7  is a drawing of partial enlargement of the cam and screw blocks in  FIG. 6 . 
         FIG. 8  is a stereogram ( 2 ) of the preferred embodiment of the present invention, showing the state of operating the detent structure to disengage the screw structure from the plunger. 
         FIG. 9  is a partial section view of the detent structure and screw structure in the preferred embodiment of the present invention, showing the state of the cam disengaging the screw structure from the plunger. 
         FIG. 10  is a drawing of partial enlargement of the cam and screw blocks in  FIG. 9 . 
         FIG. 11  is a partial section view of the plunger and screw structure in the preferred embodiment of the present invention, showing the disengaged state of the screw structure and plunger. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     As shown in  FIG. 1  to  FIG. 11 , the preferred embodiment of said fluid pressure gun device for balloon catheter includes a tubular cavity  10 , a fluid tube  20 , a pressure monitoring device  30 , a plunger  40 , a screw structure  50 , a cover casing  60  and a detent structure  70 . Wherein a chamber  12  is formed inside the cavity  10  for storing fluid (not shown in the figure), the fluid can be gas or liquid. The front end of the cavity  10  is connected to the fluid tube  20 . The chamber  12  communicates with the fluid tube  20 . The fluid tube  20  is provided with a connection fitting  22 , so that the fluid tube  20  communicates with a balloon catheter (not shown in the figure). The pressure monitoring device  30  is disposed in the cavity  10  for monitoring and indicating the pressure of the fluid. The plunger  40  is movably disposed in the chamber  12 . A piston  42  is axially pivoted at the front end of the plunger  40 , the piston  42  and the cavity  10  are fitted closely, so that the plunger  40  pulls the piston  42  to reciprocate in the chamber  12  to inject the fluid into or extract the fluid from the balloon of the balloon catheter, and to prevent the fluid from leaking between the piston  42  and the cavity  10 . An operating part  44  is formed at the back end of the plunger  40 , facilitating the rotation or axial displacement of the plunger  40 . The screw structure  50  is optionally combined with or disengaged from the plunger  40 , so that the plunger  40  resists the pressure from the fluid, and the displacement of the plunger  40  and the piston  42  is controlled. The plunger  40  is provided with a first screw thread structure  46 , in this case, the first screw thread structure  46  is a saw-tooth thread, and the first screw thread structure  46  surrounds the lateral circumference of the plunger  40 . In other embodiments, the first screw thread structure  46  can be formed on the opposite side of the plunger  40 . 
     The cover casing  60  is arranged at the back end of the cavity  10 . A chamber  62  is formed inside the cover casing  60 . The plunger  40  protrudes out of the back end of the cover casing  60  through the chamber  62 . The screw structure  50  is disposed in the chamber  62 . The screw structure  50  comprises two screw blocks  52 . The screw blocks  52  are oppositely arranged centering on the plunger  40 . The screw blocks  52  form a second screw thread structure  54  fitting the first screw thread structure  46  respectively, so that the screw blocks  52  are screwed on the plunger  40 . The screw structure  50  is provided with several springs  56  between the screw blocks  52  and the cover casing  60 . The springs  56  prop the screw block  52  and the cover casing  60  respectively. The springs  56  push the screw block  52  respectively, increasing the screwing reliability of the screw blocks  52  and the plunger  40 . The second screw thread structure  54  is formed in the central part of the side of the screw block  52  facing the plunger  40 . The springs  56  prop the portions near two ends of the screw block  52  respectively, so that the screw block  52  is stressed evenly, the screwing reliability of the screw blocks  52  and the plunger  40  is further increased. 
     When the screw block  52  is screwed on the plunger  40 , the plunger  40  can resist the pressure from the fluid. As the first screw thread structure  46  is at least formed on opposite side of the plunger  40 , the plunger  40  is supported by the screw blocks  52  at least on two opposite sides, the plunger  40  is stressed evenly. Said pressure will not induce lateral deformation of the plunger  40 . The first screw thread structure  46  and the second screw thread structure  54  have high reliability of effective screwing. Said pressure will not induce structural failure of the first screw thread structure  46  and the second screw thread structure  54 . 
     The detent structure  70  comprises two cams  71 , two arm levers  72  and one connecting rod  73 . Wherein the cam  71  is an elliptical disc, the cams  71  are pivoted between the screw blocks  52  respectively, and the cams  71  are adjacent to both ends of the screw blocks  52  far from the plunger  40  respectively. A construction line L is defined to pass through the center of the cams  71 , the construction line L radially passes through the plunger  40 . The arm levers  72  are connected to one side of the cams  71  respectively. Both ends of the connecting rod  73  are connected to the arm levers  72  respectively. When the connecting rod  73  is pulled, the arm levers  72  pull the cams  71  to rotate synchronously, as shown in  FIG. 5  to  FIG. 7 . When both ends of short diameter D 1  of the cam  71  point at the screw blocks  52 , the spring  56  provides thrust to make the screw blocks  52  lean against the plunger  40  respectively, the second screw thread structure  54  engages with the first screw thread structure  46 , as shown in  FIG. 9  to  FIG. 11 . When both ends of long diameter D 2  of the cam  71  point at the screw blocks  52 , the cam  71  pushes the screw blocks  52  to move away from the plunger  40  respectively, the second screw thread structure  54  is disengaged from the first screw thread structure  46 , the combination or disengagement of the screw blocks  52  and the plunger  40  is easy. 
     The screw blocks  52  are oppositely movable in the chamber  62 , the chamber  62  localizes the screw blocks  52  and confines the path of actuation of the screw blocks  52  against the plunger  40 , the reliability of combination or disengagement of the screw blocks  52  and the plunger  40  is enhanced, it is a better implementation option. 
     The cover casing  60  forms two through grooves  64 , the arm levers  72  pass through the through grooves  64  respectively, so that the arm levers  72  extend into the cover casing  60  respectively. The arm levers  72  are provided with a pivot  74  respectively, the pivots  74  are coaxial with the cams  71  respectively. The pivots  74  are pivoted on the cover casing  60  respectively. When the connecting rod  73  is pulled, the arm levers  72  prime the cams  71  to rotate synchronously centering on the pivots  74  respectively. 
     The connecting rod  73  is adjacent to the rear edge of the cover casing  60 , and a gripping part  75  is formed in the midsection of the connecting rod  73 , the operator can grip the gripping part  75  and pull the connecting rod  73 , the handiness of pulling the arm lever  72  is enhanced. The connecting rod  73  forms a notch  76  fitting the plunger  40 , the plunger  40  passes through the notch  76 . Hereby, when the screw structure  50  is combined with the plunger  40 , the connecting rod  73  gets closer to the plunger  40 . 
     The screw blocks  52  form several recess holes  58  respectively. Several convex pins  66  protrude from the cover casing  60 . The springs  56  are pivoted in the recess holes  58  respectively, and the springs  56  are fitted over the convex pins  66  respectively, so as to position the springs  56 . The spring  56  is lengthened by the recess hole  58 , the elastic effect of the spring  56  on the screw block  52  is increased, and the reliability of effective screwing of the first screw thread structure  46  and the second screw thread structure  54  is enhanced. 
     Two lugs  14  laterally protrude from the cavity  10 . Two embedding grooves  68  are formed inside the cover casing  60 . The lugs  14  are embedded in the embedding grooves  68  respectively, so as to oppositely position the cavity  10  and the cover casing  60 . When the operator controls the cover casing  60  and operates the plunger  40  to move linearly or rotate, the cavity  10  and the cover casing  60  are oppositely positioned, the cavity  10  will not perform rectilinear motion or rotation with the actuation of the piston  42 , the operational reliability is enhanced.