JP3626264B2 - Chemical liquid injection device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an infusion (infusion) device used for continuously injecting a medical solution such as physiological saline or a nutrient to a post-surgical patient or the like while precisely controlling the flow rate.
[0002]
[Prior art]
In hospitals, when injecting medical solutions such as saline or nutrients to patients after surgery, infusion was generally performed by the natural drop method at first, but recently, injection by machines has been performed frequently. Yes. There are a tube pressing method and a syringe method as typical injection methods by the machine.
[0003]
4 to 5 are views showing an example of the structure of the tube pressing method, FIG. 4 is a cross-sectional view thereof, and FIG. 5 is a perspective view of the tube pressing cover in FIG. 4-5, first, an infusion tube 55 having one end communicating with a chemical tank (not shown) and the other end communicating with an injection portion (not shown) is provided, and a plurality of rollers 54 are arranged on one side surface of the tube 55 in the axial direction. Set up. The rotating shaft of each roller 54 is supported so as to be slidable in the horizontal direction perpendicular to the rotating shaft.
[0004]
A cam belt 53 having a concavity and convexity larger than at least the inner diameter of the infusion tube 55 is engaged with and attached to the drive pulley 51 and the tension pulley 52 on the anti-infusion tube 55 side of the roller 54. A tube pressing cover 56 is attached to the infusion tube 55 on the side opposite to the roller. Reference numeral 57 denotes a pressing direction by the lid 56.
[0005]
When the chemical solution flows down from the chemical solution tank into the infusion tube 55 and the drive pulley 51 is driven by a drive device (not shown), the cam belt 53 rotates, and when the maximum convex portion comes into contact based on the shape of the outer surface, the roller 54 The infusion tube 55 is pressed to act in the direction of blocking the flow of the internal chemical solution, and when the maximum recess comes into contact, the cross-sectional area in the infusion tube 55 maintains the cross-sectional area where the flow rate of the chemical solution is maximum. It is arranged.
[0006]
In FIG. 4, as the drive pulley 51 is rotated in the direction of the arrow (left turn), the cam belt 53 moves from top to bottom while pressing and rotating the roller 54. Along with this, the maximum convex portion of the cam belt 53 acts smoothly so that the infusion tube 55 is moved downward from above, so that the drug solution inside the infusion tube 55 is continuously pushed out to the injection portion side.
[0007]
Moreover, the syringe system in the prior art is a method in which a syringe is filled with a predetermined chemical solution each time it is injected, and then discharged from the syringe at a predetermined speed via a speed reducer.
[0008]
[Problems to be solved by the invention]
Among the above-mentioned conventional techniques, the tube pressing method has an advantage that the chemical liquid can be continuously injected because one end communicates with the tank. On the other hand, when the flow rate is controlled, the number of revolutions given to the drive pulley is reduced. The change is transmitted to the cam belt, this is transmitted to the infusion tube via a roller, and the cross-sectional area in the infusion tube depends on the elasticity of the infusion tube. It was difficult to do.
[0009]
In addition, since the syringe method controls the speed of the piston inserted directly into the syringe, it was a method capable of significantly improving accuracy compared to the above-mentioned tube pressing method. The volume of the syringe can only inject a limited volume of the syringe, and when injecting an infusion of an amount exceeding the capacity of the syringe, it was necessary to replace the entire syringe. There was a problem that it was difficult to perform injection.
[0010]
The present invention has been made in view of such a current situation, and enables continuous infusion for a long time while having an extremely simple configuration, and controls the infusion of infusion with extremely high accuracy by a precise mechanism. The aim is to provide an infusion device to obtain.
[0011]
[Means for Solving the Problems]
The above object is achieved by the means described in the claims. That is, a syringe that sucks and stores or discharges a chemical solution according to the movement of an internal piston, a syringe holder that holds the syringe, a piston holder that holds the piston, a motor, and a motor that is linked to the motor. A ball screw shaft that rotates in rotation, a ball screw nut that engages with the ball screw shaft and advances and retreats in the axial direction of the ball screw shaft, a slide unit that is mounted on a base plate, and one end of the slide unit that is coupled to the ball screw net. A nut holder that is slidably engaged with and attached to the piston supported by the piston holder, and moves the piston of the syringe forward and backward with the operation of the ball screw nut, the motor and the ball screw shaft A coupling for connecting the ball screw shaft, a bearing for rotatably holding the ball screw shaft, Has a Taiban for mounting the device, two and check valve to operate in opposite directions, which is disposed in a flow path communicating with the syringe, and means for controlling the rotation of the motor, a bubble sensor in the discharge portion of the syringe By disposing the above, the chemical liquid precise injection device is characterized in that when a bubble exists in the syringe and is pushed out, an alarm is issued or an alarm is issued and the motor is stopped.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
1 to 3 are diagrams showing an embodiment of a chemical solution precision injection device according to the present invention. FIG. 1 is a partially broken side view, FIG. 2 is a partially broken plan view, and FIG. It is a partially broken enlarged view of a ball screw nut part.
[0013]
1-3, 1 is a check valve, 2 is a base, 3 is a bubble sensor, 4 is a syringe, 5 is a syringe holder, 6 is a piston holder, 7 is a motor, 8 is a coupling, 9 is a preload collar, 10 is a ball bearing, 11 is a ball screw nut, 12 is a ball screw shaft, 13 is a ball belling, 14 is a slide unit, 15 is a nut holder, 16 is a collar, and 17 is a ball.
[0014]
The rotation of the rotating shaft of the motor 7 mounted on the base plate 2 is transmitted to the ball screw shaft 12 through the coupling 8. The ball screw shaft 12 is rotatably supported by bearings whose both ends are mounted on the base plate 2, and a ball screw nut 11 is screwed at an intermediate portion thereof.
[0015]
The ball screw nut 11 is coupled to a nut holder 15, and one end of the nut holder 15 is slidably engaged with and attached to a slide unit 14 mounted on the base plate 2, and the other end of the nut holder 15 is a piston. It is connected to the outer end of the piston supported by the holder 6.
[0016]
The syringe 4 through which the piston is inserted is detachably attached to the syringe holder 5 by a simple operation such as using the elasticity of plastic, and is securely supported, and is located on the side opposite to the piston of the syringe 4. A flow path communicating with the storage section side and the injection side of the chemical liquid to be supplied is provided on the chemical liquid suction / discharge side, and check valves that operate in opposite directions are attached to the respective flow paths.
[0017]
When injecting a chemical solution, a predetermined chemical solution is first inhaled into the syringe 4. The piston in the syringe 4 is pulled out of the syringe 4 at such a speed that the inhalation amount of the liquid medicine into the syringe 4 becomes about 0.1 ml / second to 0.5 ml / second by means of controlling the rotation of the motor (not shown). The motor 7 is rotated in the direction.
[0018]
In accordance with the rotation of the motor 7, the ball screw shaft 12 connected by the coupling 8 rotates, and the ball screw nut 11 screwed to the ball screw shaft 12 moves to the right in FIG. Along with this, the nut holder 15 coupled to the ball screw nut 11 slides and moves in the right direction in FIG.
[0019]
As the nut holder 15 moves, the piston coupled to the nut holder 15 moves to the right in FIG. 1, and accordingly, the chemical solution flows into the syringe 4 through the check valve located on the chemical solution storage unit side, This completes the suction of the chemical solution.
[0020]
Next, when the chemical solution in the syringe 4 is injected into a predetermined position, the discharge amount of the chemical solution into the syringe 4 is about 0.1 ml / hour to 999.9 ml / hour by means of a rotation control of a motor (not shown). The motor 7 is rotated in such a direction as to push the piston into the syringe 4 (the direction opposite to that during the inhalation).
[0021]
The rotation of the shaft of the motor 7 is transmitted to the ball screw shaft 12 through the coupling 8 and is sequentially transmitted to the piston through the ball screw nut 11 and the nut holder 15 to operate the piston in the direction of pushing it into the syringe 4.
[0022]
The chemical solution filled in the syringe 4 is pushed out from the discharge side as the piston is pushed into the inside by the nut holder 15. In FIG. 1, the bubble sensor 3 is disposed in the discharge portion of the chemical solution, so that if a bubble is present in the syringe 4 and is pushed out, an alarm is issued, and if necessary, the chemical solution is discharged. It is possible to stop the injection.
[0023]
The discharged chemical liquid is fed to a predetermined injection position through a check valve 1 different from that at the time of inhalation.
[0024]
As shown in FIG. 3, the ball screw shaft 12 and the ball screw nut 11 have a structure filled with a ball 17 that circulates at the tip of the threaded portion, and the ball screw shaft 12, the ball screw nut 11, And the frictional resistance is reduced to several tenths of a general screw structure.
[0025]
This makes it possible to keep the time loss at the time of switching the piston reciprocation based on the looseness of the screw, which was inevitably generated when using general screws, at a value close to zero, Since the efficiency can be dramatically improved, the entire apparatus can be made compact, and a plurality of chemical solutions can be easily injected simultaneously in a narrow place.
【The invention's effect】
Thus, according to the present invention, the following effects are obtained.
(1) It becomes possible to inject continuously for a long time while controlling the flow rate of the chemical solution.
(2) Since there is no time lag in the operation of the apparatus due to the use of the ball screw, it becomes possible to precisely control the minute chemical flow rate.
(3) Since the entire apparatus can be made compact, it is possible to simultaneously inject a plurality of types of chemical solutions even in a narrow place.
[Brief description of the drawings]
FIG. 1 is a partially cutaway side view showing an embodiment of a chemical liquid precision injection device according to the present invention.
FIG. 2 is a partially broken plan view showing an embodiment of a chemical solution precision injection device according to the present invention.
3 is a partially broken enlarged view of a ball screw shaft and a ball screw nut portion in FIG. 1. FIG.
FIG. 4 is a diagram illustrating a conventional technique.
FIG. 5 is a diagram illustrating a conventional technique.
[Explanation of symbols]
1 Check Valve 2 Base 3 Bubble Sensor 4 Syringe 5 Syringe Holder 6 Piston Holder 7 Motor 8 Coupling 9 Preload Collar 10 Ball Bearing 11 Ball Screw Nut 12 Ball Screw Shaft 13 Ball Bearing 14 Slide Unit 15 Nut Holder 16 Collar 17 Ball 51 Drive Pulley 52 Tension pulley 53 Cam belt 54 Roller 55 Infusion tube 56 Lid 57 Direction of pressing by the lid

Claims (1)

A syringe that sucks and stores chemical liquid according to the movement of the internal piston, or discharges it,
A syringe holder for holding the syringe;
A piston holder for holding the piston;
A motor,
A ball screw shaft that rotates in conjunction with the motor;
A ball screw nut that is screwed onto the ball screw shaft and advances and retracts in the axial direction of the ball screw shaft;
A slide unit mounted on the base plate;
The syringe is coupled to the ball screw net, one end is slidably engaged with the slide unit, and the other end is coupled to a piston supported by a piston holder. A nut holder that advances and retracts,
A coupling for connecting the motor and the ball screw shaft;
A bearing for rotatably holding the ball screw shaft;
A platform on which the above devices are placed;
Two counter-support valves that operate in opposite directions, disposed in a flow path that leads to the syringe ,
Means for controlling the rotation of the motor;
Have
By arranging a bubble sensor in the discharge part of the syringe, when bubbles are present and pushed out in the syringe, an alarm is issued or an alarm is issued and the motor is stopped.
This is a precision chemical injection device.

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