JPS6352909B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an infusion device that continuously administers infusion drugs into the human body. The liquid is gradually delivered to the patient during the process. This type of piston-type pump measures the volume of the infusion fluid, thereby making it possible to obtain a highly reliable total amount of infusion fluid regardless of the viscosity of the fluid. Therefore, the reciprocating interval of a piston type pump must always be accurate. The present invention uses a reciprocating motion linked to an eccentric crank pin, so a constant amount of liquid suction and liquid delivery are always repeated, so no excessive suction or irregularities in the liquid delivery process occur. The rotation detection sensor detects the starting position of the piston-type pump's infusion operation, determines the cycle of liquid supply and suction, and measures the volume of infusion based on the number of detected cycles (Figure 6). ), and by knowing the switching position between liquid feeding and liquid suction with a rotation detection sensor, it is possible to perform liquid suctioning operation rapidly and in a short time, and not only to measure constant-speed infusion during continuous infusion, but also to perform liquid suction operation during liquid feeding operation. The constant rate infusion amount during the liquid suction operation time is added, and in addition, the rotation speed of the motor is changed using electronic control of the eccentric rotation angle speed of the crank pin in order to perform the constant speed liquid delivery operation of the piston type pump. It depends on the situation. Therefore, the purpose of this infusion device, which combines the operating structure of the present invention and the operating safety mechanism described later, is to provide excellent medical effects by being smaller and more functional. Also, in the manufacturing process, this device has excellent workability and is constructed with durability in mind, which is an effective invention. In addition, the present invention solves the conventional problems,
Furthermore, it is an object of the present invention to provide an infusion device with a mechanism that is excellent in the safety of intracorporeal infusion.

The present invention will be explained in detail below based on embodiments shown in the drawings.

Reference numeral 1 denotes a base frame of the infusion device, and a guide plate 4 having a pair of opposing guide edges 3 is fixed to a boss portion 2 projecting from the base frame 1 with mounting screws 5. The guide edge 3 formed on the guide plate 4 has a slide block 6.
is engaged to be slidable only in the vertical direction, and the upper end of a connecting plate 7 formed in a frame shape is pivotally connected to the upper end of this slide block 6 via a bearing 8 and a mounting screw 9. has been done. A motor 10 is fixedly held at the lower end of the guide plate 4, and a crank pin 12 is protruded from an eccentric position of a crankshaft 11 of the motor 10. This crank pin 1
2 is connected to the lower end of the above-mentioned connecting plate 7 via a bearing 13, and therefore, the crank pin 12 is rotated by the rotation of the motor 10.
Due to the eccentric movement of the connecting plate 7, the connecting plate 7 moves eccentrically.
Due to the eccentric movement of the slide block 6, the slide block 6 is guided by the guide plate 4 and is moved up and down. A conduction arm 14 is held through the slide block 6, and this conduction arm 1
4 is constantly biased toward the left in FIG. 2 by the elastic force of springs 15 and 16, and the distal end of this transmission arm 14 has a protrusion 17 that engages with the piston shaft of the pump, which will be described later. A switch 1 is formed at the tail end of the conduction arm 14.
8 is placed. 19 is the above crankshaft 11
This rotation detection piece 19 is installed opposite to a rotation detection sensor 20 using, for example, an electric light, and detects the rotation speed of the rotation detection piece 19 and the piston due to the rotation of the crankshaft 11. The rotation detection sensor 20 can constantly detect the operating position of the rotation detection sensor 20. 21 is a cartridge type pump, and as shown in FIG. 4, this pump 21 has a liquid suction path 2 connected to an infusion pin 31.
2, a liquid discharge path 23 communicating with the patient, a cylinder 24 provided between both of the liquid paths, and a piston shaft 25 that reciprocates within this cylinder 24.
and a liquid suction switching valve 26 and a liquid discharge switching valve 27 provided in the liquid suction path 22 and the liquid discharge path 23, and the pump 21 is connected to the base frame 1.
It is fixed to a boss portion 28 provided in the.
Also, a connecting hole 29 is provided at the tip of the piston shaft 25.
is bored in the connecting hole 29, and the projection 17 is inserted into the connecting hole 29.
are inset and connected. 30 is a flexible cover installed between the conduction arm 14 and the base frame 1.

The above is the structure of this embodiment. Next, we will discuss its operation. When the motor 10 is started in order to start infusion, the crankshaft 11 rotates, which connects the slide block via the connecting plate 7. 6 is guided by the guide plate 4 and reciprocated in the vertical direction, and the rotational speed of the crankshaft 11 is detected by the rotation detection sensor 20 and recorded and displayed by a recording circuit (not shown). The vertical movement of the slide block 6 is transmitted to the piston shaft 25 of the pump 21 via the conduction arm 14 and the protrusion 17, and the piston shaft 25 reciprocates, thereby repeatedly suctioning and discharging the fluid inside the infusion pin 31. The fluid is supplied into the patient's body. When such infusion is performed normally, it is continued by the drive of the motor 10, but if an abnormality occurs in the operation of the piston shaft 25 of the pump, for example, the infusion on the suction side and the liquid delivery side is When the tube is blocked and an overload is applied to the piston, and abnormal sliding resistance is added to the reciprocating movement of the piston shaft 25, the reciprocating movement of the piston shaft is restricted, but the slide block 6 is moved by the rotational force of the motor 10. Since the reciprocating motion is forced, the transmission arm 14 is tilted against the elastic force of the springs 15 and 16 as shown in FIGS.
The switch 18 is activated depending on the inclination of the infusion passage, and a signal indicating that an abnormality has occurred in the infusion passage is issued, and an alarm is displayed or the motor 10 is stopped. Also,
In this embodiment, the eccentric distance of the crankshaft is changed from rotational movement to linear reciprocating movement, so that the piston shaft 25 of the pump performs reciprocating movement. Since the speed changes from slow to fast to slow, fluctuations occur in the infusion speed. In order to eliminate this change in infusion speed and always infuse at a constant speed, the rotation of the motor 10 must be controlled by the rotation of the crankshaft 11. The speed can be controlled by engaging the position (angle). That is, the sixth
As shown in the figure, when the crank pin 12 is rotating at a constant speed V, the piston shaft speed is, when the crank angle θ is, the speed of the crank pin 12 is V.
Therefore, V'=V×cosθ. V′=V
To achieve this, the speed must be 1/cosθ times the speed when θ=0. In other words, if you want to obtain a piston speed of θ=0, you just need to rotate it at a speed 1/cosθ=secθ times, so in this way, the crank pin 12
By controlling the rotational speed at each position by an electronic circuit or the like to increase or decrease the rotational speed, a constant amount of fluid is infused per unit time.

As described above, the present invention is an infusion device that is equipped with a mechanism that issues an alarm when the load on the infusion pump exceeds a predetermined value. This method has the advantage that the infusion rate by using a piston type pump can always be kept stable and constant.

[Brief explanation of the drawing]

The drawings all show an embodiment of the infusion device according to the present invention, and FIG. 1 is a front view thereof, FIG. 2 is a cross-sectional explanatory view of the same essential parts, FIG. The figure is an exploded perspective view of the pump.
FIGS. 5A, 5B, and 5C are explanatory diagrams showing the operating states of the abnormality detection mechanism, and FIG. 6 is an explanatory diagram of the operation of the crank pin. DESCRIPTION OF SYMBOLS 1...Base frame, 2...Boss part, 3...Guide edge, 4...Guide plate, 5...Mounting screw, 6...Slide block, 7...Connecting plate, 8...Bearing, 9...Mounting screw, 10...Motor, 11 ...Crankshaft, 12...Crank pin, 13...Bearing, 14...Transmission arm, 15, 16...Spring, 17
...Protrusion, 18...Micro switch, 19...Rotation detection piece, 20...Rotation detection sensor, 21...Pump, 2
2...Liquid suction path, 23...Liquid discharge path, 24...Cylinder, 2
5... Piston shaft, 26... Liquid suction switching valve, 27... Liquid feeding switching valve, 28... Boss portion, 29... Connection hole, 30
...Flexible cover, 31...Infusion pin.

Claims (1)

[Claims] 1. In an infusion device equipped with a piston-type pump in an infusion circuit, a crank pin that operates eccentrically due to the rotation of a motor, a rotation detection sensor that detects the eccentric position of this crank pin, and a sub-unit connected to this crank pin and attached to a guide plate. The slide block is held elastically and is displaced when an external force greater than a set value is applied, but it reciprocates together with the slide block when an external force is applied less than the set value. It is equipped with a conduction arm that moves and is connected to the piston shaft of the piston-type pump, and when an operating load increases on the pump during infusion operation, the displacement of the conduction arm acts as a set value external force and activates an interlock switch, which generates an electrical signal such as an alarm. An infusion device characterized by a structure that emits .