JPH0334191Y2 - - 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 holding 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 feeding pump is normally constructed as shown in FIGS. 3 to 5. In FIG. 3, 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 casing 1 via a hinge 9, and a door 10 that is aligned with the finger 3 is provided on the surface of the door 10 facing the casing 1. A pressure plate 11 is provided at the position to press the tube mounted in the groove 5 against the finger 3. The upper and lower ends of this pressure plate 11 are connected to the door 10 by bolts 12 and 13, respectively.
It is attached movably in a direction perpendicular to the inner surface of the door 10. In addition, one end of the pair of springs 14 and 15 is attached to the door 10, and the other end of the spring 14, 15
The pressure plate 11 is biased in a direction so as to come into contact with the heads of the bolts 12 and 13. This door 1 again
A protrusion 16 is provided at the upper part of the inner surface of the door 10. The protrusion 16 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. 4 and 5. A pair of upper and lower frames 17 and 18 fixed at right angles to the inner front surface of the housing 1
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 the fingers 3 having a shape as shown in FIG. 5 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, the tube 23 is pressed by a single pressure plate 11 against a plurality of fingers 3 set at different positions by the eccentric cam 22. The pressing force is, for example, the pressure of two springs 14, 1.
5, the springs 14, 15
The load may not be applied uniformly due to variations in the pressing force. For example, as shown in FIG. 6, when the biasing force of the spring 15 is greater than the biasing force of the spring 14, the pressure plate 11 on the spring 15 side sufficiently presses the tube 23 against the finger 3 and closes the tube 23. However, the pressure plate 11 on the spring 14 side is the tube 2
3 may not be pressed sufficiently, and the pressure plate 11 may tilt and not close the tube 23. As a result, there was a problem that stable liquid feeding was not possible. Furthermore, the pressure plate 11 must be movably attached to the door 10 via the springs 14 and 15, resulting in a complicated structure.

(Problem to be solved by the invention) As mentioned above, according to the tube pressurizing mechanism of the conventional liquid pump, the tube is brought into contact with a plurality of fingers by one pressurizing plate pressed by a spring. Therefore, there was a problem in that the pressure plate was tilted and the load was not applied uniformly due to variations in the pressing force of the spring that pressed the pressure plate, and stable liquid feeding was not performed. Another drawback was that the pressure plate was movably attached to the door via a spring, making the structure complicated.

The present invention was developed in view of the above-mentioned problems, and has developed a tube pressurizing mechanism for a liquid pump that has a simple structure, can apply a uniform pressing force to each finger, and can perform stable liquid feeding. The purpose is to provide.

[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. a plurality of fingers that are moved, a door that is openably and closably attached to the front surface of the housing, and a presser plate that is provided on the door and holds the flexible tube between the fingers; A tube pressurizing mechanism of a liquid pump that moves liquid in the longitudinal direction of the tube by sequentially operating fingers by rotation of the eccentric cam to press and close the tube at a plurality of sequentially different positions on the tube. The presser plate is fixed at a position facing the finger of the door, and the finger is provided with an elastic member for elastically holding the tube between the finger and the presser plate.

(Function) According to the above configuration, since the plurality of fingers are each provided with an elastic member that presses the tube against the holding plate, the pressing force is separated and a uniform pressing force is generated depending on the position of the fingers. do. As a result, stable liquid feeding becomes possible. Furthermore, since the presser plate is fixed to the door, the structure is also simplified.

(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. 5 are denoted by the same reference numerals, and explanations thereof will be omitted. The features of this embodiment reside in the structure of the finger and the means for attaching the presser plate to the door. The finger 29 has one end rotatably supported by the finger shaft 3a as in the conventional example, and the other end has a U-shaped groove 2 that engages with the eccentric cam 22.
9a is formed, and a pressing portion 29b protrudes from near the base end side on the finger shaft 3a side.
The finger 29 having such a shape is integrally formed of plastic or the like, and the pressing portion 29b
has elasticity. On the other hand, the holding plate 30 is the door 10
is fixed to the inner surface of the door 10 at a position opposite to the finger 29 when rotated to the front of the housing 1, and the tube 23 is held between this holding plate 30 and the pressing portion 29b of the finger 29. It is becoming more and more pressurized.

According to this embodiment, when the door 10 is rotated to close the front surface of the casing 1, the tube 23 is attached to the presser plate 3.
0 and a pressing portion 29b of the finger 29, the finger 29 moves as the eccentric cam 22 rotates, and the pressing portion 29b presses the tube 23. At this time, the holding plate 30 is fixed to the door 10, and the pressing part 29b of the tube 23 is elastically deformed according to the amount of movement of the finger 29.
Each part of 3 is pressed with a predetermined pressing force at each position. Therefore, the conduit of the tube 23 opens and closes normally, and stable liquid feeding is performed. Moreover, since the presser plate 30 is fixed to the door 10, the structure is also simplified.

In the above embodiment, the finger 29 and the pressing part 29b are formed integrally, but as shown in FIG. 32 or the like. Further, the pressing portion 31 may be formed of an elastic member other than a leaf spring, such as a coil spring.

[Effect of the invention] As explained above, according to the invention, an elastic member for elastically holding the tube between the fingers of the finger-type peristaltic liquid pump and the holding plate is provided, and the holding plate is fixed to the door. Therefore, each part of the tube is pressed with a predetermined pressing force depending on the amount of movement of the finger.
The tube line opens and closes normally, and stable liquid delivery is performed. Moreover, the structure can be simplified.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing one embodiment of the tube pressurizing mechanism of the liquid transfer pump according to the present invention, FIG. 2 is a cross-sectional view showing another embodiment of the present invention, and FIG. FIG. 4 is a vertical sectional view showing the main parts of FIG. 3, FIG. 5 is a partially sectional plan view of FIG. 4, and FIG. 6 is a diagram showing the operation of a conventional liquid pump. FIG. 1... Housing, 3, 29... Finger, 10...
Door, 22...Eccentric cam, 23...Tube, 2
9b...pressing part (elastic member), 30...pressing plate.

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 rotation of the eccentric cams, a door attached to the front surface of the former housing so as to be openable and closable, and the door. and a holding plate which is provided to the finger and holds the flexible tube between the fingers, and the finger is sequentially operated by rotation of the eccentric cam to hold the tube at a plurality of sequentially different positions on the 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, the presser plate is fixed at a position facing the finger of the door, and the presser plate is attached to the finger. A tube pressurizing mechanism for a liquid pump, characterized in that an elastic member is provided between the tube and the tube to elastically sandwich the tube.