JPH0331299Y2 - - Google Patents

Description

[Detailed description of the invention] [Purpose of the invention] (Field of industrial application) The invention relates to a liquid pump for administering parenteral liquids, such as saline, medicinal solutions, and nutrient solutions, into living organisms. In particular, the present invention relates to a tube pressurizing mechanism for a liquid feeding pump that clamps and pressurizes a flexible liquid feeding tube (hereinafter simply referred to as a tube) attached to a finger type peristaltic liquid feeding pump between a finger and a pressure plate.

(Prior Art) Many types of liquid delivery devices have been known as liquid delivery means for administering parenteral fluids into living bodies, but the present invention is based on a finger-type peristaltic liquid delivery pump (hereinafter referred to as (simply referred to as a liquid transfer pump). This liquid pump is normally constructed as shown in FIGS. 2 to 4. In FIG. 2, a pump section 4 is provided on the front surface of the casing 1, in which a plurality of fingers 3, which will be described later, are mounted within a rectangular support frame 2. Further, a groove 5 is formed in the front surface of the support frame 2 in the vertical direction and passes approximately through the center of the support frame 2 in the width direction, and a tube (not shown) for feeding liquid is installed in the groove 5. It's becoming like that. Further, a clamp member 6 for clamping and closing the attached tube is provided at the upper part of the groove 5, and a pressure sensor 7 is provided at the lower part of the groove 5 for detecting the pressure of the liquid flowing inside the tube. and,
A bubble sensor 8 is provided to detect bubbles generated in this liquid.

On the other hand, a door 10 is rotatably attached to one side of the front surface of the housing 1 via a hinge 9,
A pressure plate 11 is provided on the surface of the door 10 facing the casing 1 for pressing the tube mounted in the groove 5 at a position aligned with the finger 3 against the finger 3.
is provided. The upper and lower ends of the pressure plate 11 are attached to the door 10 by bolts 12 and 13, respectively, so as to be movable in a direction perpendicular to the inner surface of the door 10. Further, the pressure plate 11 is biased in a direction to come into contact with the heads of the bolts 12 and 13 by a pair of springs 14 and 15, one end of which is attached to the door 10 and the other end of the spring. Further, a protrusion 16 is provided on the upper part of the inner surface of the door 10, which engages with the clamp member 6 and pushes it open when the door 10 is rotated toward the housing 1 and closed.

The pump section 4 is constructed as shown in FIGS. 3 and 4. A pair of upper and lower frames 17 and 18 are fixed to the inside of the front surface of the housing 1 in a right angle direction.
A support shaft 21 is rotatably attached to the front surface of the housing 1 through bearings 19 and 20, respectively, and a plurality of shafts, for example,
Twelve eccentric cams 22 are fixed with sequentially shifted phases. Further, between these eccentric cams 22 and the front surface of the housing 1, a plurality of fingers 3 having a shape as shown in FIG. 4 are provided corresponding to the eccentric cams 22, respectively. The finger shaft 3 is provided parallel to the front surface of the housing 1 between 18 and 18.
It is rotatably supported by a. Further, one end of these fingers 3 can be fitted into the support frame 2, and a U-shaped groove 3b that engages with the eccentric cam 22 is formed at the other end. and eccentric cam 2
2, the finger 3 swings around the finger shaft 3a, and the finger 3 sequentially presses the pressure plate 11.
approach or leave. The finger 3 is the pressure plate 11
The tip of finger 3 and pressure plate 11 when approaching
The distance between them is 2 mm to 3 mm, and the tube 23 held between them is compressed and the conduit is closed. Further, a stepping motor 24 is fixed on the upper frame 17, and a pulley 25 is attached to the drive shaft of the stepping motor 24. A timing belt 27 is provided between the pulley 26 fixed near the upper end of the support shaft 21 and this pulley 25.
is being strung up. Note that the code 28 is tube 23.
This is a fixed guide that guides the positioning of the

In the conventional finger type peristaltic liquid pump configured as described above, the rotational driving force of the stepping motor 24 is transmitted to the support shaft 21 via the timing belt 27, and the rotational driving force of the stepping motor 24 is transmitted to the support shaft 21, and the pump is attached to the support shaft 21 sequentially with a phase shift. The plurality of eccentric cams 22 are rotated. As a result, a plurality of fingers 3 are respectively engaged with the outer periphery of the eccentric cam 22 via the U-shaped grooves 3b.
is swung, and starts moving forward sequentially from the top to pressurizing plate 1.
The tube 23 is sandwiched between the tube 23 and the tube 23.
The occlusion site is moved along the longitudinal direction. and the tube 23 along the longitudinal direction of the tube 23.
The liquid inside is forced to move downward.

However, according to the conventional liquid pump configured as described above, since the plurality of fingers 3 have different rotation angles around the finger shaft 3a, as shown in FIG.
The surface facing the pressure plate 11 is not parallel to the surface of the pressure plate 11, and the tube 23 is sandwiched and pressurized between the two.
is not compressed uniformly in the diametrical direction and has a triangular shape. As a result, there was a problem that stable liquid feeding could not be carried out and complete occlusion could not be achieved. Further, if an attempt was made to forcefully close the opening in this state, a large pressing force had to be applied to the pressure plate 11. Furthermore, in the above state, when the tube 23 was pressed between the finger 3 and the pressure plate 11, there was a problem that the tube 23 was displaced in the direction of arrow A.

Furthermore, as shown in FIG. 6, it is conceivable that one end of the pressure plate 11 is rotatably connected to the finger shaft 3a, but even with this structure, the amount of compression of the tube 23 causes the finger 3 to be compressed. Pressure surface and pressure plate 11
is not parallel, and there is a similar problem.

(Problem to be solved by the invention) As mentioned above, in the tube pressurizing mechanism of the conventional liquid pump, the pressurizing surface of the finger and the pressurizing plate are not necessarily parallel, and the tube is not compressed uniformly, so it is not stable. There was a problem in that it was not possible to send liquid properly or to completely close the tube, and the position of the tube shifted when pressurized.

The present invention has been developed in view of the above problems, and the tube can be sandwiched between the finger and the pressure plate to apply pressure uniformly, and the tube of the liquid feeding pump can be stably fed and completely blocked. The purpose is to provide a pressure mechanism.

[Structure of the invention] (Means for solving the problem) In order to achieve the above object, the present invention includes a plurality of eccentric cams rotatably supported in a housing, and rotation of the eccentric cams. and a pressure plate that clamps and presses the flexible tube between the fingers, and the fingers are sequentially operated by the rotation of the eccentric cam to sequentially move the flexible tube. In a tube pressurizing mechanism of a liquid pump that moves liquid in the longitudinal direction of the tube by pressing and closing the tube at a plurality of different positions, the tube is held between the tip of the finger and the pressurizing plate. The pressurizing member is rotatably provided.

(Function) According to the above configuration, when the finger swings due to the rotation of the eccentric cam, the pressure member that presses the tube held between the finger and the pressure plate is rotatably attached to the finger. Since the pressure surfaces of the fingers are all approximately parallel to the pressure plate, a uniform load is applied to the tube.
Stable liquid delivery and complete occlusion are possible.

(Example) Hereinafter, an example of the tube pressurizing mechanism of the liquid feeding pump according to the present invention will be described with reference to the drawings.

FIG. 1 shows an embodiment of the present invention. In the figure, parts that are the same or equivalent to those of the conventional example shown in FIG. 4 are designated by the same reference numerals, and their explanation will be omitted. The feature of this embodiment is that the finger 3 presses the tube 23 on the pressure plate 11.
The other parts are the same as those of the conventional example. One end is finger shaft 3
A circular hole 3 is provided on one side facing the pressure plate 11 near the other end of the finger 3 rotatably supported by the finger 3.
c is formed, and the one side of this hole 3c is cut out. A disk portion 31 formed at the tip of the arm 30 of the pressure member 29 is provided in the hole 3c.
are rotatably fitted, and are prevented from falling off by means such as side plates (not shown). Pressure member 2
9 is formed into a rectangular plate shape with a width equal to the thickness of the finger 3 and a length longer than the outer diameter of the pressed tube 23.

According to this embodiment, the tube 23 is connected to the pressure member 2
9 and the pressure plate 11, and when the finger 3 swings due to the rotation of the eccentric cam 22 and approaches the pressure plate 11, the tube 23 moves toward the pressure plate 11.
is pressed against the pressure member 29 by. At this time, since the pressing member 29 is rotatable with respect to the finger 3, it becomes substantially parallel to the pressing plate 11 and presses the tube 23 with a uniform force. Therefore, a uniform load is applied to the entire surface of the tube 23, and the tube 23 is deformed with its upper and lower surfaces parallel to each other. As a result, the liquid delivery within the tube 23 is stabilized, and even when it is sealed, it is possible to completely seal it. Furthermore, since no force is applied to push the tube 23 in the direction of arrow A, the tube 23 will not be displaced.

[Effects of the invention] As explained above, according to the invention, since the pressure member is rotatably provided at the tip of the finger of the finger type peristaltic liquid pump, the tube can be held between the pressure plate and pressurized. When this is done, all the pressurizing surfaces of the fingers become approximately parallel to the pressurizing plate, and a uniform load is applied to the tube, allowing stable liquid feeding and complete closure.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view showing an embodiment of the tube pressurizing mechanism of the liquid pump according to the present invention, Fig. 2 is a perspective view of a conventional liquid pump, and Fig. 3 is the main part of Fig. 2. 4 is a partial cross-sectional plan view of FIG. 3, FIG. 5 is a cross-sectional view showing the operation of the conventional tube pressure mechanism, and FIG. 6 is a partial cross-sectional view of the conventional tube pressure mechanism. It is a cross-sectional view showing an example. DESCRIPTION OF SYMBOLS 1... Housing, 3... Finger, 11... Pressure plate, 22... Eccentric cam, 23... Tube, 29
...Pressure member.

Claims (1)

[Scope of utility model registration request] A plurality of eccentric cams rotatably supported within a housing, a plurality of fingers that are respectively moved back and forth by the rotation of the eccentric cams, and a pressure plate that clamps and presses the flexible tube between the fingers. and liquid feeding for moving the liquid in the longitudinal direction of the tube by sequentially operating the finger by rotation of the eccentric cam to press and close the tube at a plurality of sequentially different positions on the tube. What is claimed is: 1. A tube pressurizing mechanism for a liquid feeding pump, characterized in that a pressurizing member is rotatably provided at the tip of the finger to sandwich the tube between the finger and the pressurizing plate.