JPH0835486A - Continuous infuser - Google Patents

Abstract

(57) [Summary] [Purpose] To control the flow rate of fluid with high precision in a continuous infusion device and perform a fixed amount or arbitrary discharge in a fixed period. [Structure] In a tubular housing 1, a balloon 2 into which a fluid is injected and a flow rate control element 3 that constitutes a flow path having a minute cross-sectional area are provided. And the piping member 4 which consists of a soft material which forms a discharge flow path is connected to the fluid outlet. The flow rate control device 5 has an actuator that is operated by a drive signal from the electric control circuit so as to compress and restore the piping member 4. This opens and closes the flow path. In addition, the discharge rate is the external input switch 7
Can be set by, and the information is displayed on the liquid crystal display 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a continuous injector for ejecting a fluid by means of a balloon made of an elastic material and a flow control element utilizing a tube resistance, and more particularly to a flow control device capable of ejecting a stable flow rate. Is.

[0002]

2. Description of the Related Art As a continuous injector as described above, Japanese Patent Publication No. 62-501333 discloses a balloon in which a thin tube is arranged at the tip of a balloon. As shown in FIG. 8, this is a continuous infuser using a glass thin tube as a flow rate control element 81, and a balloon 83 provided in a tubular housing 82 is filled with a liquid before use and maintains a certain internal pressure. ing. Due to the contraction pressure of the balloon 83 and the fluid resistance of the flow control element 81, a very small amount of fluid was discharged.

[0003]

However, with the thin tube described in the above-mentioned prior art (Japanese Patent Publication No. 62-501333), the flow rate can be reduced as fluid resistance, but the balloon contracts. There is a problem that high accuracy cannot be obtained because the change in pressure directly changes the discharge flow rate. Further, there is a problem that the discharge amount cannot be controlled arbitrarily, and the application is limited as compared with other commonly used rotary pumps and syringe pumps.

Therefore, the present invention solves such a problem, and an object of the present invention is to provide a flow rate control device capable of controlling a discharge flow rate with high accuracy and performing a constant amount or arbitrary discharge in a constant period. The purpose of the present invention is to provide a continuous infusion device equipped with the device.

Another object of the present invention is to provide a flow control device of low power consumption, that is, to realize a portable continuous injector using a small battery as a power source.

Still another object of the present invention is to provide a continuous injector which is capable of preventing excessive ejection due to malfunction and is excellent in safety.

[0007]

The continuous infusion device of the present invention comprises:
The present invention is characterized by including a piping member formed of a soft material that forms a discharge flow path and has a restoring force, and a flow rate control device that has an actuator that opens and closes the discharge flow path by compressing and restoring the piping member.

Further, the electric control circuit for controlling the actuator has a storage means for holding the flow rate characteristic data by the balloon and the flow rate control element, and performs a comparison calculation between the discharge rate data and the flow rate characteristic data set from the outside. Therefore, it is desirable to control the opening / closing of the piping member by the actuator.

Further, the flow control device may be detachable from the balloon and the flow control element.

The actuator is composed of a motor having a screw part in a part of the output rotary shaft, a piston member engaged with the screw part, and a syringe member for guiding the reciprocating motion of the piston member. It is desirable to arrange a piping member made of a soft material such as a tube in the space, and open and close the flow path by compressing and restoring the piping member by reciprocating movement of the piston member.

Further, it is desirable that the actuator is provided with a detecting device for detecting the reciprocating position of the piston member to detect the opening / closing of the flow path. Further, this detection device is provided with a through hole in the piston member, and the through hole reciprocates the piston member to compress the piping member to close the flow passage, and the position where the compression is released to restore the flow passage due to the restoring force of the pipe member. It is more desirable to provide through holes at two positions of the syringe member that are matched with each other at the opening position, and detect the matched position by the photoelectric element.

Further, the electric control circuit warns the outside when the matching time of the through hole of the piston member and the matching hole of the syringe member calculated from the drive signal of the motor and the matching time of the through hole obtained from the detection device are different. It is desirable to provide an informing means for informing.

[0013]

The operation of the continuous infusion device of the present invention is as follows.

First, in the first aspect of the invention, a pipe member is provided in the discharge passage constituted by the balloon and the flow rate control element, and the pipe member is compressed and restored by the actuator to arbitrarily discharge the flow. It opens and closes the road. As a result, a certain amount of fluid is discharged accurately. Further, since the fluid in the channel is not directly acted on and the channel is indirectly opened and closed through the piping member, the fluid is not chemically affected.

According to the second aspect of the present invention, the flow rate characteristic data generated when the balloon and the flow rate control element are formed and the discharge amount data set from the outside are compared and calculated, and the piping by the actuator is used. By controlling the opening and closing of the members, a desired flow rate can be obtained within a certain period.

According to the third aspect of the present invention, by making the flow control device removable, it is possible to connect to various types of injectors, and the flow control device can be easily replaced. It allows you to do it.

Further, in the invention according to claim 4, the motor is not rotating when the flow path is opened / closed by forming the actuator by the motor, the piston member, the syringe member and the like. As a result, the power consumption of the actuator is reduced.

Further, in the fifth and sixth aspects of the invention, the position of the reciprocating motion of the piston is detected, so that excessive discharge or defective discharge due to some malfunction is detected. Particularly, in the invention according to claim 6, a light passage is formed by a through hole provided in the piston and the syringe, and the position is detected by an optical sensor by utilizing this passage.

Further, in the invention according to the seventh aspect, the warning is given to the outside based on the detection result, so as to prevent excessive ejection or ejection failure due to some malfunction.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a schematic view of an embodiment of a continuous injector according to the present invention, and is shown in a partial cross section. At the outlet of the balloon 2 provided in the tubular housing 1, a flow rate control element 3 forming a flow path having a minute cross-sectional area is arranged. The flow rate control element 3 controls the flow rate of the fluid by the tube resistance. Then, the hollow pipe member 4 made of a soft material such as silicon rubber is connected to the outlet of the flow control element 3. The flow rate control device 5 includes an actuator (a specific structure will be described later) that opens and closes a flow path by compressing and restoring the piping member 4, and an electric control circuit for operating this actuator (a specific system will be described later). , An external input switch 7 for setting a discharge amount, a liquid crystal display 8 for displaying a set value (120 ml is discharged per day in the embodiment), and a notifying means for notifying a defect to the outside. An alarm device (not shown)
And so on. The functions of the external input switch 7 include, for example, increase in discharge amount, decrease in discharge amount, change of discharge set time unit, discharge start / stop, discharge temporary stop / return, and the like. Since the fluid is initially injected into the balloon 2 made of an elastic material, a septum (made of rubber) 6 can be provided in a part of the balloon 2 to inject it with an injection needle or the like.

FIG. 2 shows the change in the discharge amount with the passage of time. The conventional balloon and flow rate control element alone have a drawback that the discharge rate decreases with the passage of time as shown by the flow rate characteristic 21 (dotted line). Therefore, it is useful to have the flow rate control device 5 of this embodiment. That is, the flow rate characteristic data 21 consisting only of the balloon 2 and the flow rate control element 3 is held in advance in the ROM which is a storage means, and is compared and calculated with the discharge amount data input from the outside (for example, from the external input switch 7). Based on this result, the piping member 4 is opened and closed intermittently at the calculated time. As a result, the flow rate can be kept constant for a fixed period (for example, 30 minutes, 1 hour) (flow rate characteristic 22, solid line),
It is possible to increase the flow rate (flow rate characteristic 23 / dotted line) for a certain period. In either case, the concept is to prevent excessive ejection at the initial stage of ejection, and to release the amount suppressed at the initial stage at the final stage of ejection.

Further, since the flow rate control device 5 is provided with a detection device (specific structure will be described later) for detecting the compressed / restored state of the pipe member 4 by optical / mechanical, magnetic or the like, excess due to malfunction. Discharge and insufficient discharge can be prevented,
It is possible to provide a continuous infuser having excellent safety. The position of the flow rate control device 5 may be placed between the balloon 2 and the flow rate control element 3.

FIG. 3 shows another embodiment of the continuous injector in which the flow control device 31 can be detached. The flow rate control device 31 is provided with a piping member 33 having connecting members 32 at both ends in order to connect to the balloon piping member and the piping member for injection. Therefore, the flow rate control device 31 can be used as an optional item of the continuous infusion device.
Also, it is possible to obtain a desired discharge amount by connecting to various injectors such as a conventional drip device.

FIG. 4 shows an embodiment of an actuator included in the flow rate control device. FIG. 4A is a top view for explaining the flow path opening / closing section, and FIG. 4B is a cross-sectional view taken along the line AA.

A screw is cut on a part of the output shaft 42 of the motor 41. Further, the inner surface of the piston member 43 is threaded so as to engage with the screw of the output shaft 42.
The outer shape of the piston member 43 is a shape other than a cylinder so that the piston member 43 does not rotate but slides in the axial direction due to the rotation of the output shaft 42 (in the case of the present embodiment, a rectangular parallelepiped shape). Further, a syringe member 44 for guiding the movement of the outer wall surface of the piston member 43 and the piston member 43.
The inner wall surface of will be a mirror surface to reduce friction during movement. In addition, a piping member 45 made of a soft tube that forms the discharge channel of the continuous injector is arranged between the piston member 43 and the syringe member 44. In this state, the piping member 4
Since 5 is not compressed, the flow path is open.

Then, the opening / closing operation of the flow path will be described with reference to FIG. The output shaft 42 is rotated by driving the motor 41, and the piston member 43 is prevented from being rotated by the syringe member 44. Therefore, the piston member 43 moves upward along the inner wall of the syringe member 44 in the drawing. And
The flow path is closed by crushing the piping member 45. Further, by rotating the output shaft 42 in the reverse direction, the piston member 43 moves downward in the drawing, and the flow path is opened by the restoring force of the piping member 45. With the above operation, the opening and closing of the flow path can be easily performed. The amount of movement of the piston member 43 can be arbitrarily set by arbitrarily selecting the amount of rotation of the motor 41. Therefore, the compression amount of the piping member 45 can be set appropriately.

FIG. 6 is a sectional view showing an embodiment of a flow rate control device provided with a safety mechanism for detecting the open / closed state of the flow path. A through hole 61 is provided in a part of the piston member 43, and two through holes 62 and 63 are also provided in the syringe member 44. When the piston member 43 moves upward and crushes the piping member 45, that is, when the flow path is closed, the through hole 61 of the piston member 43 and the one through hole 62 of the syringe member 44 are aligned with each other. To arrange. Further, when the piston member 43 moves downward and reaches the position where the flow path is opened due to the restoring force of the piping member 45, the through hole 61 of the piston member 43 and the other through hole 63 of the syringe member 44 are aligned. Arrange to do.

Further, a light emitting element 64 is provided on one side of each through hole of the syringe member 44, and a light receiving element 65 is provided at a position facing each other. Therefore, the light of the light emitting element 64 moves when the piston member 43 moves to close the flow path,
Since it reaches the light receiving element 65 through the through hole only in the open state, it is possible to detect the open / closed state of the flow path by detecting the signal of the light receiving element 65. Further, instead of the light emitting element 64, a light emitting element and a light receiving element are arranged side by side, and instead of the light receiving element 65, a reflecting member for reflecting the light of the light emitting element is provided, and the through holes 61, 62 or the through holes 61,
The light may be reflected and reach the light receiving element when 63 match. Note that the detection of the open / closed state of the flow path is not limited to the light detection of the present embodiment, and there are means such as a mechanical switch / hall element.

FIG. 7 is an embodiment illustrating the electrical control circuit and system of the present invention. As shown in FIG.
1. A CPU 72 for mainly performing rotation control / discharge amount calculation / timing calculation of a motor, a switch 73 for setting a desired discharge amount from the outside, a display body 74 for displaying a set value, and a motor. A motor driver 75 for driving, a position detection circuit 76 for detecting the position of the piston member to detect opening and closing of the flow path, an alarm 77 for notifying the outside that a malfunction has occurred, and an actuator for controlling the flow rate. It is composed of a certain motor unit 78.

The motor unit 78 is, as described above, at least driven by the motor and the motor.
It is composed of a mechanism for opening and closing the flow path of a piping member made of a soft material. Flow rate characteristic data for only the balloon and the flow rate control element are written in advance in a ROM (not shown) provided in the CPU 72. Then, the control signal to the motor driver 75 is determined by performing comparison calculation with the desired discharge amount data input from the switch 73. The motor unit 78 opens and closes the flow path of the piping member by reciprocating movement of the piston member as the motor rotates forward and backward in response to the drive signal from the motor driver 75. In addition, the position detection circuit 76 drives a light emitting element that detects the position of the piston member, receives a signal from the light receiving element, and transmits the signal to the CPU 72.

The CPU 72 opens and closes the flow path calculated from the output signal timing from the position detection circuit 76 (timing at which the light detection signal from the light receiving element is received) (actual measurement value) and the calculated motor drive signal. Compare the time difference with the timing (calculated value). The CPU 72 determines this, and if the value is an abnormal value (when the timings of the two do not match, in other words, when the time difference between the two exists at a level that deviates from the error range of the measurement system), the notification means is used. It drives an alarm 77 and issues a warning to the outside. As the alarm 77, various notification methods such as an audible alarm, a visual alarm, and a vibration alarm can be used.

The continuous infusion device of the present invention supplies a fixed amount of fluid over a relatively long period of time, such as injecting a medicinal solution into a living body, releasing a liquid fragrance to the outside, and supplying water or nutrients to plants or the like. Most suitable for stable discharge.

[0033]

As described above, the present invention has the following effects.

First, according to the first aspect of the present invention, it is possible to arbitrarily open and close the discharge passage by compressing and restoring the piping member by the actuator.
A certain amount of fluid can be discharged accurately. Further, since the fluid in the channel is not directly acted on and the channel is indirectly opened and closed through the piping member, the fluid is not chemically affected. Therefore, many kinds of fluids can be used.

According to the second aspect of the invention, by comparing the flow rate characteristic data in the case where the balloon and the flow rate control element are configured with the discharge amount data set from the outside, it is possible to obtain a predetermined period. A desired flow rate can be obtained easily and accurately. Then, the discharge is performed so that the initial discharge amount and the final discharge amount are balanced, which is particularly effective in applications in which the discharge needs to be performed for a relatively long time. Above all, its practical value is very large in medical application fields.

According to the third aspect of the present invention, by making the flow control device removable, it becomes possible to connect to various types of injectors. Further, replacement of the flow rate control device (fault, selection of various types of flow rate control device) can be easily performed.

According to the fourth aspect of the present invention, since the actuator is constituted by the motor, the piston member, the syringe member, etc., the motor is not rotating when the flow path is opened / closed. It is possible to reduce power consumption. Therefore, a portable continuous injector using a small battery as a power source can be realized.
That is, since the flow rate can be controlled with high accuracy and the place of use is not selected, it is also effective for home treatment and the like, for example, in medical liquid injection. Moreover, since the rotational movement of the motor is converted into the linear movement via the screw portion, the noise can be reduced and the linear movement accuracy can be improved as compared with the linear movement by the solenoid.

According to the inventions of claims 5 and 6,
Since the position of the reciprocating motion of the piston is detected,
Excessive ejection or ejection failure due to some malfunction can be accurately detected. Particularly, according to the invention described in claim 6, it becomes possible to detect accurately and safely (there is no electric leakage phenomenon) by using the optical means.

Further, according to the invention described in claim 7, since the warning is notified to the outside based on the detection result,
It is possible to prevent excessive ejection or ejection failure due to some malfunction. Therefore, it is possible to provide a highly safe continuous infusion device. This is very important for a medical continuous infusion device and its significance is great.

[Brief description of drawings]

FIG. 1 is a schematic view showing an embodiment of a continuous infusion device of the present invention.

FIG. 2 is a discharge characteristic diagram of an embodiment of the continuous infusion device of the present invention.

FIG. 3 is a schematic view showing another embodiment of the flow control device of the continuous infuser of the present invention.

4A and 4B are diagrams showing an actuator constituting the flow rate control device of the present invention, in which FIG. 4A is a top view thereof and FIG. 4B is a sectional view thereof.

FIG. 5 is a cross-sectional view for explaining an operating state of an actuator of the flow rate control device of the present invention.

FIG. 6 is a cross-sectional view for explaining a flow path open / closed state detection mechanism in the flow rate control device of the present invention.

FIG. 7 is a system configuration diagram of an electric control circuit of the present invention.

FIG. 8 is a schematic diagram of a continuous infuser as a conventional example.

[Explanation of symbols]

1 Housing 2 Balloon 3 Flow Control Element 4, 33, 45 Piping Member 5, 31 Flow Control Device 6 Septum 7 External Input Switch 8 Liquid Crystal Display 21 Flow Characteristics with Conventional Balloon and Flow Control Element 22 Flow Characteristics of the Present Invention (Constant Flow rate) 23 Flow rate characteristics of the present invention (flow rate increase / decrease) 32 Connect member 41 Motor 42 Motor output shaft 43 Piston member 44 Syringe member 64 Light emitting element 65 Light receiving element 71 Power supply 72 CPU 73 Switch 74 Display 75 Motor driver 76 Position Detection circuit 77 Alarm 78 Motor unit

Claims (7)

[Claims] 1. A continuous injector for ejecting a fluid by a balloon made of an elastic material and a flow control element using a tube resistance, and a pipe member made of a soft material having a restoring force and forming a discharge flow path, and the pipe member. And a flow rate control device having an actuator that opens and closes the discharge flow path by compressing and restoring. 2. An electric control circuit for controlling the actuator has a storage unit for holding flow rate characteristic data by the balloon and the flow rate control element, and stores discharge amount data and the flow rate characteristic data set from the outside. The continuous infusion device according to claim 1, wherein opening and closing of the piping member by the actuator is controlled by performing a comparative calculation. 3. The continuous infusion device according to claim 1, wherein the flow control device is detachable from the balloon and the flow control element. 4. The actuator includes a motor having a screw portion on a part of an output rotary shaft, a screw member engaging with the screw portion, and a piston member having a sliding surface in the same direction as the output rotary shaft, the output rotary shaft. Of a syringe member having a sliding surface with respect to the piston member so that the piston member reciprocates in the same direction as the output rotation shaft by forward and reverse rotations of the piston member, and the piping member is arranged in the reciprocating space of the piston member. 4. The continuous flow path according to claim 1, 2 or 3, wherein the piping member compresses and restores between the piston member and the syringe member by the reciprocating motion of the piston member to open and close the flow path. Injector. 5. The continuous injector according to claim 4, wherein the actuator is provided with a detection device for detecting the reciprocating position of the piston member to detect the opening and closing of the flow path. 6. The detection device is provided with a through hole in the piston member, and the through hole reciprocates the piston member to compress the piping member to close the flow path,
6. The sustaining device according to claim 5, wherein through holes are provided at two positions of the syringe member that are in agreement with each other at a position where the compression member is released and the restoring force of the piping member opens the flow passage, and the coincident portion is detected by a photoelectric element. Injector. 7. The electric control circuit for controlling the actuator is configured such that the through hole of the piston member and the through hole of the syringe member, which are calculated from a drive signal of the motor, coincide with each other, and the through hole obtained by the detection device. 7. The continuous infusion device according to claim 6, further comprising an informing means for informing a warning to the outside when the coincidence timings of the holes are different.