WO2015041088A1

WO2015041088A1 - Infusion pump

Info

Publication number: WO2015041088A1
Application number: PCT/JP2014/073664
Authority: WO
Inventors: 良一赤井; 高橋　秀典
Original assignee: ニプロ株式会社
Priority date: 2013-09-17
Filing date: 2014-09-08
Publication date: 2015-03-26
Also published as: JP6369469B2; JPWO2015041088A1

Abstract

　The device permits setting of a high flow rate mode in which a solution is fed at a higher flow rate than in a normal usage flow rate zone in which there is no possibility that drops dripping down within a drip tube (100) will coalesce. In the case that the normal usage flow rate zone is selected, the setting is such that multiple drops drip down from the drip tube (100) in a single cycle of solution feed, and in the case in which the high flow rate mode has been set, the setting is such that drops dripping down from the drip tube (100) are deliberately induced to coalesce, and a single drop drips down from the drip tube (100) in a single cycle of solution feed without fail. Even during the high speed mode produced by this setting, it is possible to ensure accurate flow rate determination on the basis of the output of a drip sensor (8), and transfusion at a high flow rate is possible.

Description

Infusion pump

The present invention relates to an infusion pump used for injecting medical chemicals into the body.

As an infusion pump, there is a finger type (peristaltic type) infusion pump. The finger-type infusion pump, for example, drives the finger forward and backward with respect to the infusion tube with the infusion tube connected to the infusion bag between the finger and the tube holding plate, and presses the infusion tube with the finger. This is an infusion pump that delivers the infusion by doing so.

As a finger type infusion pump, there is an infusion pump of a system (full press system) in which an infusion tube is completely closed with a finger. Further, an infusion pump of an intermediate pressure closing method (semi-occlusion method) in which an infusion tube is not completely closed with a finger has been proposed (see, for example, Patent Documents 1 and 2). This semi-occluded infusion pump is, for example, a liquid feeding finger that delivers liquid without completely crushing the infusion tube, and an infusion tube arranged on the upstream side and the downstream side of the liquid feeding direction of the liquid feeding finger. It is equipped with a closing finger or the like that performs complete pressure closing and opening.

In such an infusion pump, for example, a drip tube connected to the infusion tube is disposed upstream of the infusion pump in the infusion feeding direction, and a drip sensor for detecting a drip in the drip tube is provided. Based on the output of the drip sensor, the actual number of infusions (mL / h) is calculated by measuring the number of drops dropped in the drip tube and the drop time interval (for example, Patent Document 3). reference). Then, the actual flow rate calculated in this way is compared with the set flow rate to determine a flow rate abnormality or the like.

Japanese Patent No. 3595136 JP-A-55-005485 JP 2002-336350 A

By the way, the infusion pump may be set so that a plurality of droplets (for example, two droplets) are dropped in the drip cylinder by one cycle of liquid feeding. In the infusion pump having such a setting, when the flow rate of the liquid feeding becomes high, the liquid droplets dropped in the drip tube may be connected in one cycle of the liquid feeding (for example, 2 drops are originally 1 drop). It may be a drop). In such a situation, an error may occur in the flow rate calculated based on the output of the dropping sensor, so that it is impossible to guarantee the accuracy of the flow rate determination (flow rate abnormality determination) based on the output of the dropping sensor.

Therefore, conventionally, the upper limit is a flow rate at which there is no possibility that the droplets dropped in the drip tube are connected to each other. However, when using an infusion pump, there is a case where liquid feeding at a flow rate exceeding such an upper limit value is required, and it is desired to provide an infusion pump capable of infusion at such a high flow rate.

The present invention has been made in view of such circumstances, and an object thereof is to provide an infusion pump capable of infusion at a high flow rate.

The present invention relates to a pump mechanism that presses an infusion tube to deliver the infusion in the infusion tube, and a drip that detects a drop that drops in a drip tube disposed upstream of the pump mechanism in the infusion feeding direction. Assuming an infusion pump comprising a sensor and capable of performing flow rate control for controlling the driving of the pump mechanism according to a set flow rate and determining the flow rate of the liquid delivery based on the output of the dropping sensor. Yes. In such an infusion pump, as a control mode of the pump mechanism, it is possible to set a high flow rate mode in which liquid is dropped at a flow rate larger than the normal use flow rate range where there is no possibility that droplets dropping in the drip tube are connected to each other. In the case of the normal use flow rate range, it is set so that a plurality of droplets are dropped from the drip tube in one cycle of liquid feeding, and when the high flow rate mode is set, 1 of liquid feeding is set. The inhalation period of the infusion solution during the cycle is shortened, and one droplet is dropped from the infusion tube in one cycle of the liquid feeding.

According to the present invention, when the flow rate is in the normal use flow rate range (the flow rate range in which the flow rate determination accuracy can be ensured), a plurality of droplets (for example, 2 droplets) are set to be dropped from the drip tube in one cycle of liquid feeding. On the other hand, when the high flow rate mode is set, the inhalation period of the infusion in one cycle of the liquid feeding is shortened (droplet is intentionally connected), and the infusion tube is removed from the infusion cylinder in one cycle of the liquid feeding. One drop is set to drop. In this way, in the high flow mode, the droplets dropped from the drip tube are intentionally connected so that one drop is always dropped from the drip tube in one cycle of liquid delivery. Even so, it is possible to ensure the accuracy of the flow rate determination (flow rate abnormality determination) based on the output of the dropping sensor.

In the present invention, the pump mechanism is arranged on the upstream side in the infusion feeding direction of the infusion feeding direction of the infusion feeding direction of the infusion feeding finger by the advancing / retreating movement, and is disposed on the upstream side of the infusion feeding direction of the infusion feeding finger. An upstream closing finger for closing and opening, a downstream closing finger that is disposed downstream of the liquid feeding direction of the liquid feeding finger and that closes and opens the infusion tube by advancing and retreating, and the liquid feeding When the high flow rate mode is set, the structure includes a finger, an upstream closing finger, and a cam and a cam shaft for individually driving the forward and backward driving fingers of the downstream closing finger. The infusion period during one cycle of liquid feeding may be shortened by changing the rotational speed of the cam shaft of the pump mechanism during one cycle of liquid feeding.

According to the infusion pump of the present invention, the accuracy of the flow rate determination based on the output of the drip sensor can be ensured even in the high flow rate mode, so that the infusion at a high flow rate is possible.

It is an external appearance perspective view which shows an example of the infusion pump to which this invention is applied. It is a front view of the infusion pump of FIG. It is a schematic block diagram which shows the infusion pump of FIG. 1 in the state which opened the door. It is a fragmentary sectional side view which shows the structure of a pump mechanism. It is a figure which shows typically the structure of the drive part of a pump mechanism. It is a block diagram which shows the structure of the control system of an infusion pump. It is operation | movement explanatory drawing of the pump mechanism shown in FIG. It is operation | movement explanatory drawing of the pump mechanism shown in FIG. It is operation | movement explanatory drawing of the pump mechanism shown in FIG. It is a figure which shows the discharge period and suction period in 1 cycle of liquid feeding.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

An example of the infusion pump of the present invention will be described with reference to FIGS.

The infusion pump 1 of this example is a semi-occluded infusion pump, and includes a pump body 11 and a door 12 that closes the front surface side (tube attachment position) of the pump body 11. The door 12 is swingably (rotatably) supported by the pump body 11 via

hinges

13 and 13, and is opened from the position at which the front side of the pump body 11 is completely closed (for example, 180 degrees). Oscillate until the position).

The pump main body 11 and the door 12 are provided with a door lock mechanism 14 for holding the closed state when the door 12 is closed. The door lock mechanism 14 includes a door lock lever 14a disposed on the door 12 side, a hook 14b disposed on the pump main body 11 side, and the like, and the door lock lever 14a is rotated with the door 12 closed. Then, the door 12 can be locked in the closed state by being hooked on the hook 14b.

A tube mounting guide (guide groove) 111 is provided on the front wall 110 of the pump body 11. The tube mounting guide 111 includes an upstream guide portion 111a, a pump finger portion 111b enlarged from the upstream guide portion 111a in a rectangular shape, and a downstream guide portion 111c in order from the upstream side in the infusion feeding direction. The pump finger portion 111b faces the distal end portions of the liquid feeding fingers 21... 21 of the liquid feeding portion 20 of the pump mechanism 2 to be described later and the distal end portions of the

closing fingers

31 and 31 of the

valve portions

30A and 30B.

The upstream guide portion 111a of the tube mounting guide 111 is formed in a laterally curved shape (curved shape), and the tip portion thereof serves as an infusion tube inlet 1a. Further, the downstream guide portion 111c on the downstream side of the pump finger portion 111b is formed in a shape extending linearly in the vertical direction. A lower end portion of the downstream guide portion 111c serves as an infusion tube outlet 1b. A bubble sensor (for example, an ultrasonic sensor) 71 that detects bubbles mixed in the infusion tube T attached to the pump main body 11 is disposed in the downstream guide portion 111c.

The groove width of the upstream guide portion 111a and the groove width of the downstream guide portion 111c are respectively large corresponding to the outer diameter (diameter) of an infusion tube (for example, made of polyvinyl chloride or polybutadiene) T connected to the chemical solution bag. The infusion tube T can be attached to the infusion pump 1 by fitting the infusion tube T into the upstream guide portion 111a and the downstream guide portion 111c.

A tube clamp 112 is provided on the upstream guide portion 111a. The tube clamp 112 is a member that temporarily holds the infusion tube T when the tube is attached to the infusion pump 1, and the clamp is automatically released when the door 12 is closed after the tube is attached. . A clamp lever (not shown) is provided in the vicinity of the tube clamp 112. When the infusion tube T is mounted, the tube clamp 112 can be opened by operating the clamp lever. it can.

On the other hand, on the inner surface side of the door 12, a closing sensor 72 for detecting closing on the downstream side of the infusion tube T is provided. Further, a liquid feeding part pressing plate 24 is provided on the inner surface side of the door 12. The liquid feeding part pressing plate 24 is provided at a position corresponding to the liquid feeding fingers 21... 21 of the liquid feeding part 20 described later. The liquid feeding part presser plate 24 is spaced from the distal end surface 21a of the liquid feeding finger 21 in the last retracted position with the door 12 closed, corresponding to the outer diameter (diameter) of the infusion tube T. (Refer to FIG. 4, FIG. 7, etc.).

Further, valve portion pressing plates 34 are provided on the inner surface side of the door 12. The valve

part pressing plates

34 and 34 are provided at positions corresponding to the

respective closing fingers

31 and 31 of the upstream valve part 30A and the downstream valve part 30B, which will be described later. These valve

part holding plates

34 and 34 are in the state where the door 12 is closed, and the outer diameter (diameter) of the infusion tube T with respect to the tips of the

projections

31a and 31a of the closing

fingers

31 and 31 in the last retracted position. ) With an interval corresponding to (see FIG. 4, FIG. 7, etc.).

An elastic member (not shown) such as a compression coil spring is disposed on the back side (door 12 side) of the liquid feeding part pressing plate 24 and the valve

part pressing plates

34, 34, respectively, and the infusion tube T is The load that the infusion tube T receives from each

finger

21, 31 when being pressed by the

liquid feeding fingers

21, 21 of the liquid feeding part 20 and the closing

fingers

31, 31 of the upstream and downstream valve parts 30 A, 30 B. If it is too large, it is retracted to the door 12 side. Thereby, the overload which the infusion tube T receives from each

finger

21 and 31 can be reduced, and the lifetime of the infusion tube T can be extended.

Further, on the front surface of the door 12, a liquid crystal panel 3a of the liquid crystal display unit 3 for displaying various information and an operation unit 4 in which switches described later are arranged are arranged. Further, an indicator 5 that informs the operating state of the infusion pump 1 is arranged at the upper center of the door 12.

When the infusion tube T is set in the infusion pump 1 having the above configuration, the door 12 is opened, and the infusion tube T connected to the chemical solution bag is connected to the [upstream guide portion 111a] → [pump finger portion 111b] → [ The infusion tube T is attached to the infusion pump 1 in the order of the downstream guide portion 111c]. After such tube mounting is completed, the door 12 is closed, and the door 12 is locked in the closed state by the door lock mechanism 14 to complete the setting of the infusion tube T. In this example, as described above, in a state where the door 12 is closed, the tube clamp 112 of the upstream guide portion 111a is opened. Further, when the door 12 is opened after completion of the infusion, the infusion tube T is closed by the tube clamp 112, and free flow that is a free fall of the infusion is prevented.

Here, the infusion set applied to the infusion pump 1 of the present embodiment includes an infusion bag for storing a medicinal solution, an infusion tube 100 (see FIG. 3) for visually confirming the flow rate of the infusion solution, An upstream infusion tube T connecting the infusion tube 100, a downstream infusion tube T connected to the infusion tube 100, a roller clamp provided in the middle of the downstream infusion tube T, and an infusion tube T It is comprised by the injection needle (venous needle) etc. which are connected to the front-end | tip part. The infusion tube T between the infusion tube 100 and the roller clamp of such an infusion set is mounted on the pump body 11 in the manner described above, and the infusion tube 100 is disposed upstream of the infusion pump 1 in the infusion feeding direction. (See FIG. 3).

And the infusion pump 1 of this embodiment is provided with the dripping sensor 8 which detects the droplet dripped inside the said infusion tube 100, as shown in FIG. The dropping sensor 8 includes a light emitting unit 8a that outputs light such as infrared rays and a light receiving unit 8b that receives output light from the light emitting unit 8a. The drip sensor 8 is detachably attached to the drip tube 100 by a clamp (not shown) or the like, and in the attached state, the optical axis of the light emitting unit 8a coincides with the droplet dropping position, and the light emitting unit 8a and the light receiving unit. 8b is opposed to the drip tube 100. When the light receiving unit 8b receives the light from the light emitting unit 8a (when the light from the light emitting unit 8a passes through without being blocked by the droplet), the light receiving unit 8b outputs, for example, an OFF signal, When the light from the light emitting unit 8a is blocked by the droplet, the light receiving unit 8b is configured to output an ON signal. An output signal of the dropping sensor 8 (light receiving unit 8b) is input to the control unit 300 described later.

-Pump mechanism-
Next, a specific configuration example of the pump mechanism 2 will be described with reference to FIGS. In FIG. 4, each finger is shown without being cut.

The pump mechanism 2 includes an upstream valve unit 30A, a liquid feeding unit 20, a downstream valve unit 30B, a liquid feeding unit pressing plate 24, valve

unit pressing plates

34 and 34, a driving unit 200, and the like. As will be described later, the driving unit 200 individually includes the three liquid feeding fingers 21... 21 of the liquid feeding unit 20, the upstream valve unit 30A, and the closing

fingers

31 and 31 of the downstream valve unit 30B. Move forward and backward (forward movement or backward movement).

<Liquid feeding part>
The liquid feeding unit 20 includes three liquid feeding fingers 21. Of these three liquid feeding fingers 21... 21, the upstream one in the infusion feeding direction is the first liquid feeding finger 21, the middle one is the second liquid feeding finger 21, and the downstream one is the third liquid feeding finger. It may be called a finger 21. In the present embodiment, the first liquid feeding finger 21, the second liquid feeding finger 21, and the third liquid feeding finger 21 have the same configuration. Therefore, in the following description, one liquid feeding finger 21 (first Only the configuration of the single liquid delivery finger 21) will be described with reference to FIGS.

The liquid feeding finger 21 is a member having a rectangular cross section, and the front-rear direction of the pump main body 11 (the X direction perpendicular to the longitudinal direction of the infusion tube T attached to the pump main body 11 (perpendicular to the front wall 110 of the pump main body 11). Direction)). The liquid feeding finger 21 is slidably supported by a guide member 50 (see FIG. 4), and can move forward and backward in the front-rear direction (X direction) of the pump body 11. The guide member 50 is supported and fixed to the pump body 11.

The liquid feeding finger 21 is moved forward and backward (forward movement or backward movement) by a driving unit 200 described later, and when the liquid feeding finger 21 is in the last retracted position, as shown in FIGS. 4 and 7A, etc. The distal end surface 21a of the liquid finger 21 is disposed at a position (a position corresponding to the outer peripheral surface of the infusion tube T) in contact with the outer peripheral surface of the infusion tube T (circular state) attached to the pump body 11. Further, when the liquid feeding finger 21 moves forward from this state (the state at the last retracted position), the infusion tube T is pressed during the forward movement process. Here, since the infusion pump 1 of this example is a semi-occlusion type, the infusion tube T is driven so as not to be completely occluded as shown in FIG. 8 when the infusion finger 21 is in the most advanced position. The stroke of the forward / backward movement of the liquid feeding finger 21 by the part 200 is set.

<Valve part>
Next, the upstream valve portion 30A and the downstream valve portion 30B will be described with reference to FIGS. Since the upstream side valve unit 30A and the downstream side valve unit 30B have the same configuration, only one valve unit (upstream side valve unit 30A) will be described in the following description.

The valve unit 30A (30B) includes a closing finger 31. The closing finger 31 is a member having a rectangular cross section, and is similar to the liquid feeding finger 21 described above in the front-rear direction of the pump body 11 (the X direction (pump body perpendicular to the longitudinal direction of the infusion tube T attached to the pump body 11). 11 in the direction perpendicular to the front wall 110)). Further, a protruding portion 31 a is provided at the distal end portion of the closing finger 31. The closing finger 31 is slidably supported by a guide member 50 (the same guide member 50 as the liquid feeding finger 21 of the liquid feeding section 20), and can move forward and backward in the front-rear direction (X direction) of the pump body 11. It has become.

The closing finger 31 is moved forward and backward (forward movement or backward movement) by the driving unit 200 described later, and when the closing finger 31 is in the last retracted position, as shown in FIG. 4 and FIG. The tip of 31a is arrange | positioned in the position (position corresponding to the outer peripheral surface of the infusion tube T) which contacts the outer peripheral surface of the infusion tube T (perfect circle state) with which the said pump main body 11 was mounted | worn. Further, when the closing finger 31 moves forward from this state (the state at the last retracted position), the infusion tube T is pressed during the forward movement process. Here, since the infusion tube T is completely closed in the valve portion 30A (30B), when the closing finger 31 is in the most advanced position, the infusion tube T is completely as shown in FIG. The stroke of the forward / backward movement of the closing finger 31 by the drive unit 200 is set so as to be closed.

<Driver>
As shown in FIG. 5, the drive unit 200 includes

cams

221a, 221b, and 221c for individually advancing and retracting the

liquid feeding fingers

21 and 21 of the liquid feeding unit 20, and upstream and

downstream valve units

30A and 30B. Are provided with

cams

231a, 231b, a cam shaft 201, a stepping motor 202, and the like for individually driving the closing

fingers

31, 31 respectively, and the

cams

221a, 221b, 221c, 231a, 231b are cam shafts 201, respectively. Is attached to be integrally rotatable. The cam shaft 201 is disposed along the vertical direction of the pump body 11 (the arrangement direction of the fingers 21... 21, 31, 31).

A timing pulley (driven pulley) 203 is attached to the upper end portion of the cam shaft 201 so as to be integrally rotatable. Further, a timing pulley (drive pulley) 204 is provided on the rotating shaft 202a of the stepping motor 202 so as to be integrally rotatable. A timing belt 205 is wound between the timing pulley 203 of the cam shaft 201 and the timing pulley 204 on the stepping motor 202 side, and the cam shaft 201 is rotated by driving of the stepping motor 202.

In the present embodiment, the above-described driving of the stepping motor 202 (rotation of the cam shaft 201) causes the

liquid feeding fingers

21 and 21 of the liquid feeding section 20 and the closing fingers of the upstream and

downstream valve sections

30A and 30B. The cam shapes of the

cams

221a, 221b, 221c, 231a, and 231b are set so that the

fingers

31 and 31 are driven forward and backward by the operations shown in FIGS.

Here, in this embodiment, since the stepping motor 202 is used as an electric motor that applies a rotational force to the camshaft 201, the rotational speed of the camshaft 201 is arbitrarily changed during one cycle of liquid feeding (see FIG. 10). Is possible. That is, as is well known, the stepping motor 202 can control the rotation speed of the rotating shaft 202a by controlling the driving pulse (for example, duty control) applied to the motor driver. Therefore, by changing the drive pulse given to the stepping motor 202 during one cycle of liquid feeding (changing the duty ratio of the drive pulse), the rotational speed of the camshaft 201 can be arbitrarily changed within that cycle. It is. Accordingly, for example, as shown in FIG. 10, even if the period (time) of one cycle is the same, the ratio between the discharge period of liquid feeding and the suction period can be variably set (for example, FIG. The suction period of FIG. 10 (B) can be shortened with respect to A).

The driving of the above stepping motor 202 is controlled by the control unit 300. The stepping motor 202, the control unit 300, and the like are supplied with electric power from a battery built in the infusion pump 1 or a commercial power source.

As the drive unit 200, a mechanism in which an electric motor and a rotation-translation mechanism (for example, rack and pinion) are combined may be applied, or a drive using a solenoid as a drive source may be applied.

-Liquid crystal display and operation unit-
The liquid crystal display unit 3 includes a liquid crystal panel 3 a and a drive driver (not shown), and the liquid crystal panel 3 a is disposed on the front surface of the door 12. On the screen of the liquid crystal panel 3a, operation information such as integrated amount [mL], scheduled infusion volume [mL], flow rate [mL / h], alarm information (message, etc.), and various settings by the user The user setting screen is displayed.

As shown in FIG. 2, the operation unit 4 includes a start switch 41 for starting infusion, a stop switch 42 for stopping an infusion operation and an alarm, a fast-forward switch 43 used when preparing for infusion, a display changeover switch 44, and a numerical value setting. An up switch 45, a numerical value setting down switch 46, an integrated amount reset switch 47, an infusion needle size selection switch 48, and the like are provided.

The display changeover switch 44 is a switch for switching the display to items (for example, flow rate, scheduled amount, scheduled time, high flow rate mode, etc.) for inputting numerical values and the like.

The numerical value setting up switch 45 and the numerical value setting down switch 46 are switches for increasing or decreasing numerical values such as a flow rate, a predetermined amount, and a scheduled time. It consists of a total of three switches: a numerical value setting switch for the eye and a numerical value setting switch for the third digit on the left side.

-Control unit-
Next, the control unit 300 will be described.

The control unit 300 is composed mainly of a microcomputer or the like, and includes a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), a nonvolatile RAM, an I / O interface, and the like. A bus line for connecting the functional units to each other is provided.

As shown in FIG. 6, the control unit 300 is connected to the operation unit 4, the bubble sensor 71, the blockage sensor 72, the power switch 7 (for example, disposed on the back surface of the pump main body 11), and the like. A sensor 8 is connected. Signals from switches and sensors of the operation unit 4 are input to the control unit 300. The control unit 300 is connected to the liquid crystal display unit 3, the indicator 5, the sound generation unit 6, the stepping motor 202 for driving the pump mechanism 2, and the like.

Then, the control unit 300 controls the rotational speed of the stepping motor 202 of the pump mechanism 2 according to the set value (set flow rate) of the infusion flow set by operating the switches of the operation unit 4. Adjust the variable. In this example, the flow rate can be set in units of [1 mL / h] within the range of 1 mL / h to 1200 mL / h. This flow control will be described later. Further, the control unit 300 calculates the flow rate based on the output of the dropping sensor 8. This flow rate calculation process will also be described later.

-Explanation of operation of pump mechanism-
Next, the operation of the pump mechanism 2 will be described with reference to FIGS. 7 to 9, each finger is shown without being cut.

[S1] First, FIG. 7A is a diagram showing a state (initial state) in which the infusion tube T is mounted on the pump body 11 and the door 12 is closed. In this initial state, only the closing finger 31 of the downstream valve portion 30B is at the most advanced position, and the infusion tube T is completely closed by the protrusion 31a of the closing finger 31.

[S2] From the state of FIG. 7A, the closing finger 31 of the upstream valve portion 30A moves forward, and the closing finger 31 moves to the most advanced position. The infusion tube T is completely occluded (FIG. 7B).

[S3] From the state of FIG. 7B, the closing finger 31 of the downstream valve portion 30B moves backward from the most advanced position, and the closing finger 31 moves to the last retracted position. The infusion tube T on the upstream side is completely opened (FIG. 7C).

[S4] From the state shown in FIG. 7C, the first liquid delivery finger 21 of the liquid delivery section 20 moves forward and presses the infusion tube T (FIG. 8A). When the infusion tube T is pressed by the first infusion finger 21, the infusion in the infusion tube T is sent downstream. Following the forward movement of the first liquid feeding finger 21 as described above, the second liquid feeding finger 21 and the third liquid feeding finger 21 sequentially move forward (FIGS. 8B to 8C). When the infusion tube T is pressed by the

infusion fingers

21 and 21, the infusion in the infusion tube T is further sent to the downstream side. Thus, in this example, the infusion in the infusion tube T is fed by the peristaltic motion of the three liquid feeding fingers 21. Here, since the infusion pump 1 of this example is a semi-occlusion type, even if each of the liquid feeding fingers 21 of the liquid feeding unit 20 reaches the most advanced position, it is shown in FIGS. 8 (A) to 8 (C). As such, the infusion tube T is not completely crushed.

[S5] From the state of FIG. 8C, the closing finger 31 of the downstream valve portion 30B moves forward and the closing finger 31 moves to the most advanced position. T is completely occluded (FIG. 9).

[S6] From the state shown in FIG. 9, the closing finger 31 of the upstream valve section 30A and the three liquid feeding fingers 21... 21 of the liquid feeding section 20 are moved to the last retracted position. The infusion solution is sucked in the process of moving the liquid fingers 21... 21 to the last retracted position, and the initial state shown in FIG. The period from the state of FIG. 9 (suction start) to the state of FIG. 7B (suction stop) is the liquid feeding suction period, and from the state of FIG. 7C (discharge start) to FIG. 8A. The period from the operation of FIG. 8C to the state of FIG. 9 (discharge stop) is the liquid discharge period.

With the above operation, one cycle of liquid feeding is completed, and by sequentially repeating such a cycle, the infusion in the infusion tube T can be continuously sent out downstream. The liquid flow rate can be variably adjusted by controlling the cycle of the liquid supply cycle. Further, as described above, by changing the drive pulse applied to the stepping motor 202 within one cycle of liquid feeding, the liquid ejection period and the suction period can be variably set during that cycle (see FIG. (See FIG. 10).

-Features-
Next, the characteristic part of this embodiment is demonstrated.

First, as an infusion tube of an infusion set, there are an infusion tube with 20 drops per mL and an infusion tube with 60 drops per mL. In this embodiment, the infusion tube 100 has 20 infusion tubes 100. A case where an infusion bag is used will be described.

Moreover, in the infusion pump 1 of this embodiment, it is set so that 0.1 cc (0.1 mL) of liquid can be delivered in one cycle of the above-described liquid feeding, and 20 drops of the above-mentioned 20 drops in one cycle of liquid feeding. It is set so that two droplets are dropped from the drip tube 100 (0.05 cc / 1 droplet).

In the infusion pump 1 (semi-enclosed infusion pump) having such a setting, when the flow rate of the liquid feed reaches a high flow rate exceeding 600 mL / h, for example, the inside of the drip tube 100 is dropped in one cycle of the liquid feed. The droplets are connected to each other, and there is a high possibility that a drop of 2 drops will be a drop of 1 drop. Also, depending on the flow rate, there may be a mixture of a state in which droplets are connected and a state in which droplets are not connected. When such a connection of droplets occurs, an error may occur in the flow rate calculated based on the output of the dropping sensor 8. That is, if droplets dropping in the drip tube 100 are connected in one cycle of liquid feeding, there is an error in the count value of the number of droplets dropped in the drip tube 100 and the droplet dropping time interval. Therefore, the flow rate cannot be calculated accurately. In addition, a user such as a nurse checks the flow rate by looking at the liquid droplets dropping in the drip tube. However, when the liquid droplets are connected as described above, it is difficult to visually confirm the flow rate.

Considering such points, conventionally, the flow rate is such that there is no possibility that a droplet dropped in the drip tube 100 is connected, and the flow rate can guarantee the accuracy of the flow rate calculation based on the output of the drop sensor 8 (for example, 600 mL). / H) The following flow range is defined as a normal use range (hereinafter also referred to as a normal use flow range). However, when using an infusion pump, there are cases where liquid feeding at a flow rate exceeding such a normal use flow rate range is required.

Therefore, in the present embodiment, as a drive mode of the pump mechanism 2, a high flow rate mode in which liquid feeding is performed in a high flow rate region (a high flow rate region of 601 mL / h or more) exceeding the normal use flow rate region can be set. At the same time, by solving the problems that hinder the realization of the infusion at the high flow rate, it is possible to cope with the case where the infusion at the high flow rate is necessary. Control and processing in the high flow rate mode will be described later.

Hereinafter, control and processing executed by the control unit 300 will be described below.

<Control and processing in the normal flow rate range>
First, control and processing in a normal use flow rate range of 600 mL / h or less will be described.

(A1) In the normal use flow rate range, the flow rate from 1 mL / h to 600 mL / h can be set by operating the switches of the operation unit 4. The control unit 300 supplies a drive pulse corresponding to the set flow rate set by the operation of the operation unit 4 (a drive pulse having a duty ratio corresponding to the set flow rate) to the stepping motor 202 of the pump mechanism 2, and the stepping motor By controlling the rotational speed of 202, the liquid feed flow rate of the pump mechanism 2 is controlled to the set flow rate.

(A2) When the drop of droplets is detected when the pump mechanism 2 is stopped in the normal use flow rate range (when the control unit 300 receives an ON signal (droplet detection signal) from the drop sensor 8) ), The control unit 300 displays a message indicating the occurrence of free flow on the screen of the liquid crystal panel 3a of the liquid crystal display unit 3, or drives the sound generation unit 6 to generate a buzzer sound. Informing a user such as a nurse that a free flow has occurred.

(A3) When the flow rate is in the normal use flow rate range, the control unit 300 determines the flow rate abnormality by calculating the flow rate based on the output of the dropping sensor 8. Specifically, the control unit 300 counts the number of droplets dropped per unit time (for example, per minute) of the droplets dropped in the drip tube 100 based on the output signal of the drop sensor 8 (counts ON signal). The liquid flow rate (mL / h) is calculated (converted) from the droplet count value. For example, when a drip tube with 20 drops per mL is used as the drip tube 100, the volume of the droplet per drop is 0.05 mL, so the number of drops per minute (drop count value) Is a na drop, the flow rate (mL / h) is calculated from the drop count value na from the arithmetic expression [flow rate = 0.05 (mL / 1 drop) × na (drop / min) × 60]. To do.

Then, the controller 300 sequentially executes a flow rate calculation process based on the output of the drip sensor 8 during the infusion in the normal use flow rate region, and calculates the calculated flow rate (actual flow rate) and the set flow rate (1 mL / The difference between the set flow rate and the calculated flow rate (flow rate difference) is calculated using the set flow rate from h to 600 mL / h. When the calculated flow rate difference is within a predetermined allowable range (a range in which the flow rate can be regarded as normal), it is determined that the flow rate is normal. On the other hand, when the flow rate difference is out of the allowable range, it is determined that the flow rate is abnormal. When it is determined that the flow rate is abnormal, the control unit 300 displays a message indicating the abnormal flow rate on the screen of the liquid crystal panel 3a of the liquid crystal display unit 3 or drives the sound generation unit 6 to generate a buzzer sound. To inform a user such as a nurse that the flow rate is abnormal.

(A4) When the pump mechanism 2 is in a driving state in the normal use flow rate range, when droplet dropping is not detected for a certain period (when the ON signal (droplet detection signal) is not output from the dropping sensor 8 for a certain period), The control unit 300 displays a message indicating that the liquid is in the liquid state on the screen of the liquid crystal panel 3a of the liquid crystal display unit 3, and also drives the sound generation unit 6 to generate a buzzer sound. The user such as a nurse is informed that this is the state. In addition, about the fixed period (time) which determines the said air liquid, the value calculated | required empirically by experiment, calculation, etc. is set.

Here, when liquid feeding is performed in the normal use flow rate range, the suction period and the discharge period in one cycle are controlled by changing the rotation speed of the camshaft 201 (rotation speed of the stepping motor 202) in the above-described one cycle. Set the ratio. Specifically, the suction period is set to a length that can secure the time required for two droplets to drop from the drip tube 100 in one cycle. The discharge period is set as long as possible after securing such a suction period. When the discharge period is set to be long in this way, the forward speed of the liquid feeding fingers 21... 21 and the closing

fingers

31 and 31 during the discharge period can be slowed, and stable liquid feeding is performed while suppressing pulsation and the like. be able to.

<High flow mode setting process>
In this embodiment, as described above, liquid feeding is normally performed in the normal use flow rate range of 600 mL / h or less, but the high flow rate mode is set when infusion at a high flow rate is necessary. be able to.

The high flow rate mode is set by, for example, operating the display changeover switch 44 of the operation unit 4 to display the item “high flow rate mode setting” on the screen of the liquid crystal panel 3 a of the liquid crystal display unit 3. By pressing the start switch 41, the high flow rate mode can be set. When returning to the normal use flow rate liquid delivery mode, the display changeover switch 44 is operated to display the item “high flow rate mode release” on the liquid crystal panel 3a of the liquid crystal display unit 3 and start in this display state. By pressing the switch 41, it is possible to cancel the high flow rate mode and return to the liquid supply mode at the normal use flow rate.

<Control and processing in high flow mode>
When the high flow rate mode is set by the above operation, the control unit 300 performs the following control and processing.

(B1) When the high flow rate mode is set, the flow rate from 601 mL / h to 1200 mL / h can be set by operating the switches of the operation unit 4. The control unit 300 supplies a drive pulse corresponding to the set flow rate set by the operation of the operation unit 4 (a drive pulse having a duty ratio corresponding to the set flow rate) to the stepping motor 202 of the pump mechanism 2, and the stepping motor 202. By controlling the rotation speed of the pump mechanism 2, the liquid feed flow rate of the pump mechanism 2 is controlled to the set flow rate.

(B2) The controller 300 receives an ON signal (droplet detection signal) from the drop sensor 8 when the drop of the droplet is detected when the pump mechanism 2 is in a stopped state when the high flow rate mode is set. The control unit 300 displays a message indicating the occurrence of free flow on the screen of the liquid crystal panel 3a of the liquid crystal display unit 3 or drives the sound generation unit 6 to generate a buzzer sound. To inform a user such as a nurse that a free flow has occurred.

(B3) When the high flow rate mode is set, the suction period during one cycle of liquid feeding is shortened, and control is performed so that one droplet is dropped from the drip tube 100 in one cycle. This control will be described.

First, the suction period in one cycle of liquid feeding is the period from FIG. 9 to FIG. 7A as described above. If this suction period is shortened, the upstream side valve unit 30A in the suction period is reduced. The retraction speeds of the closing finger 31 and the three liquid feeding fingers 21... 21 of the liquid feeding unit 20 are increased. That is, if the suction period is shortened, the suction speed is increased. The suction speed (suction force) increases as the suction period becomes shorter, and the droplet dropping interval becomes shorter. Therefore, by making the suction period as short as possible and increasing the suction speed (suction force), it is possible to intentionally connect the droplets dropped in the drip tube 100. Here, when a chemical solution is fed at a high flow rate of 1200 mL / h, since the cycle cycle (time) of the feeding is very short, no matter how the ratio between the discharge period and the suction period in one cycle is set. The droplets that drop in the drip tube 100 are always connected (one droplet is always dropped in one cycle).

In consideration of such points, in this embodiment, regardless of the magnitude of the set flow rate (601 mL / h to 1200 mL / h) set in the high flow rate mode, FIG. 10 (B) and FIG. 10 (C) As shown in FIG. 5, the change control of the rotation speed of the camshaft 201 (rotation speed of the stepping motor 202) during one cycle is executed so that the suction period during one cycle is the same period as when the flow rate is 1200 mL / h. This ensures that one drop is dropped in one cycle. In this manner, by making sure that one droplet (0.1 cc / 1 droplet) is dropped in one cycle of liquid feeding in the high flow rate mode, the drop sensor even in the high flow rate mode. The accuracy of the flow rate abnormality determination based on the output of 8 (accuracy equivalent to the normal use flow rate range) can be secured.

Such a process is set so that one drop is surely dropped in one cycle, and the flow rate is calculated based on the output of the drop sensor 8 to determine a flow rate abnormality. Specifically, the control unit 300 counts the number of drops per unit time (for example, per minute) of droplets dropped in the drip tube 100 from the output signal of the drop sensor 8 (counts the ON signal), and The flow rate (mL / h) of the liquid feeding is calculated (converted) from the droplet count value. Here, in the high flow rate mode, as described above, since one drop is surely dropped in one cycle, the volume of the drop per drop is 0.1 mL. When the number of drops per minute (drop count value) is nb drops (nb is equivalent to na / 2), the flow rate (mL / h) is calculated using the drop count value nb using the formula [flow rate = 0.1 (mL / 1 drop) × nb (drops / min) × 60].

Then, the control unit 300 sequentially executes a flow rate calculation process based on the output of the drip sensor 8 during the infusion in the high flow rate mode, and calculates the calculated flow rate (actual flow rate) and the set flow rate (601 mL / The set flow rate from h to 1200 mL / h) is used to calculate the difference between the set flow rate and the calculated flow rate (flow rate difference). When the calculated flow rate difference is within a predetermined allowable range (a range in which the flow rate can be regarded as normal), it is determined that the flow rate is normal. On the other hand, when the flow rate difference is out of the allowable range, it is determined that the flow rate is abnormal. When it is determined that the flow rate is abnormal, the control unit 300 displays a message indicating the abnormal flow rate on the screen of the liquid crystal panel 3a of the liquid crystal display unit 3 or drives the sound generation unit 6 to generate a buzzer sound. To inform a user such as a nurse that the flow rate is abnormal.

(B4) When the pump mechanism 2 is in the driving state when the high flow rate mode is set, when droplet dropping is not detected for a certain period (when the ON signal (droplet detection signal) is not output from the dropping sensor 8 for a certain period). The control unit 300 displays a message indicating that the liquid is in the liquid state on the screen of the liquid crystal panel 3a of the liquid crystal display unit 3, or drives the sound generation unit 6 to generate a buzzer sound. To inform the user such as a nurse that the liquid is empty. In addition, about the fixed period (time) which determines the said air liquid, the value calculated | required empirically by experiment, calculation, etc. is set.

<Effect>
As described above, according to the present embodiment, in the high flow rate mode in which liquid droplets dropped in the drip tube 100 are not likely to be connected to each other and are supplied at a flow rate larger than the normal use flow rate region, the drip tube 100 is used. Are set so that one drop is surely dropped from the drip tube in one cycle of liquid feeding, so even in the high flow rate mode, the drop sensor 8 The accuracy of the flow rate abnormality determination based on the output of (the accuracy equivalent to the normal use flow rate range) can be ensured. This enables infusion at a high flow rate.

In addition, by setting so that one droplet is surely dropped in one cycle of liquid feeding in the high flow rate mode, a user such as a nurse can move the inside of the infusion tube 100 even in the high flow rate mode. Since the flow rate can be easily converted from the number of dropped droplets and the dropping time interval, the flow rate can be visually confirmed.

-Other embodiments-
In the above embodiment, the normal use flow rate range and the high flow rate range are separated using 600 mL / h as a threshold value, but an appropriate value is set for the threshold value according to the setting state of the pump mechanism 2 and the like. May be.

In the above embodiment, the flow rate is calculated by counting the number of droplets dropped per unit time (per minute), but the present invention is not limited to this. For example, the flow rate may be calculated by measuring the time required for the count value of the droplets counted from the output of the drop sensor 8 to reach a predetermined value. Further, the flow rate may be calculated by obtaining the dropping time interval of the droplets dropped in the drip tube 100 from the output of the dropping sensor 8.

In the above embodiment, the example in the case of using a drip tube having 20 drops per mL as the drip tube 100 has been described, but the present invention is not limited to this, and the drip per mL as the drip tube 100 is used. The present invention can also be applied when using a drip tube having 60 drops.

In the above embodiment, in the normal use flow rate range, two droplets are dropped from the drip tube 100 in one cycle of liquid feeding, but the number of drops in one cycle is three or more. There may be.

In the above embodiment, the number of the liquid feeding fingers 21 provided in the liquid feeding unit 20 is three, but the present invention is not limited to this, and the number of the liquid feeding fingers 21 provided in the liquid feeding unit 20 is two. There may be one or four or more.

In the above embodiment, a plurality of (three) liquid feeding fingers 21... 21 of the liquid feeding unit 20 are arranged at intervals, but the liquid feeding fingers 21. May be. Further, the closing

fingers

31, 31 of the upstream and downstream valve portions 30 </ b> A, 30 </ b> B may also be arranged in a state of being close to the liquid feeding finger 21 of the liquid feeding portion 20.

Although the example which applied this invention to the semi-occlusion type infusion pump 1 is shown in the above embodiment, this invention is not limited to this, The infusion tube T by the liquid feeding finger 21 of the liquid feeding part 20 It is also applicable to a full press infusion pump that completely closes the fluid.

The present invention can be used for an infusion pump used for injecting a medical drug solution into the body.

DESCRIPTION OF SYMBOLS 1 Infusion pump 11 Pump main body 12 Door 2 Pump mechanism 20 Liquid feeding part 21 Liquid feeding finger 30A Upstream valve part 30B Downstream valve part 31 Blocking finger 3 Liquid crystal display part 3a Liquid crystal panel 4 Operation part 8 Drop sensor 100 Drip cylinder 200 Drive unit 202 Stepping motor 300 Control unit

Claims

A pump mechanism that presses the infusion tube to deliver the infusion in the infusion tube, and a drip sensor that detects a drop that drops in the drip tube disposed upstream of the pump mechanism in the infusion feeding direction. In an infusion pump capable of performing flow rate control for controlling the driving of the pump mechanism according to a set flow rate, and performing flow rate determination for determining the flow rate of liquid feeding based on the output of the dropping sensor,
As a control mode of the pump mechanism, it is possible to set a high flow rate mode in which liquid is fed at a flow rate larger than a normal use flow rate range where there is no possibility that droplets dripping in the drip tube are connected,
When it is in the normal use flow rate range, it is set so that a plurality of droplets are dropped from the drip tube in one cycle of liquid feeding, and when the high flow rate mode is set, it is set in one cycle of liquid feeding. An infusion pump, wherein the inhalation period of the infusion is shortened and one drop is dropped from the drip tube in one cycle of the liquid feeding.
The infusion pump according to claim 1,
The pump mechanism is arranged on the upstream side of the liquid feeding direction of the liquid feeding finger, which is capable of moving forward and backward and presses the liquid feeding tube in the forward movement process, and is closed and opened by the forward and backward movement. An upstream closing finger that is disposed downstream of the liquid feeding direction of the liquid feeding finger and that closes and opens the infusion tube by advancing and retreating, the liquid feeding finger, the upstream A closed closing finger on the side, and a cam and a camshaft for individually moving forward and backward for each finger of the closed closing finger on the downstream side,
When the high flow rate mode is set, the rotational speed of the cam shaft of the pump mechanism during one cycle of liquid feeding is changed to shorten the infusion period of the infusion during one cycle of the liquid feeding. Infusion pump.