JPH05228210A - Infusion system - Google Patents

Abstract

PURPOSE:To measure the position of a suction piece in a syringe with acoustic waves and determine the infusion quantity by moving a moving body moving the suction piece in the syringe with a drive mechanism, and providing an acoustic range finder fitted with a sound transmission section and a sound reception section on a main body and the moving body. CONSTITUTION:When a syringe 3 is fitted to a mount section 22 and a slider 24 pushes a suction piece 23 in the arrow (a) direction at the preset speed with a drive mechanism 25, the preset quantity of a chemical in the syringe 3 is extruded and injected into a patient through an infusion pipe and an injection needle. An acoustic range finder 50 fitted on this side of the lower section of the frame of a fitting section 5 is provided with a sound transmission section 51 fitted to a coupling member 32, a sound reception section 52 fitted to one end of the drive mechanism 25, and a CPU system controlling them. The acoustic range finder 50 rectifies the output of a mixer 86 mixing the sweep wave from the sound transmission section 51 and the sweep wave from the sound reception section 52, and the shift distance of the suction piece 23 is determined based on the specific acoustic frequency generating the maximum value of the rectified wave-form.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an infusion device for injecting various chemicals, blood or the like into a human body using a syringe type infusion pump.

[0002]

2. Description of the Related Art A conventional infusion device is disclosed in Japanese Patent Application Laid-Open No. 48-622.
89, Japanese Utility Model Publication 57-76637, Japanese Patent Publication 6
As shown in JP-A 2-44505 and JP-B-63-44390, a syringe containing a drug solution is attached to a mounting portion of a main body, and a reciprocating slider presses a sucker at a constant speed to automatically I try to infuse.

The amount of movement of the slider is measured by a rotary encoder attached to the rotary shaft of the motor after linear-rotation conversion or a brush of a linear potentiometer attached to the slider to measure the actual infusion volume and monitor the infusion state. Was being implemented. The slider movement amount monitoring method using the rotary encoder may miss a serious failure in which the slider is not moving when the rotary motion / linear motion conversion mechanism between the motor and the slider is damaged or slips.

[0004]

The linear potentiometer, when used, converts the change in the minute resistance by the movement of the slider into the movement distance, but it is easily affected by external noise. Further, there is a problem that the mechanical contact portion between the linear potentiometer and the brush fixed to the slider is easily worn, and the service life with time is short. A method for solving these problems is disclosed in Japanese Patent Application No. 3-2 of the present applicant.
No. 24751.

An object of the present invention is to provide an infusion device which does not require mechanical contact and which monitors movement of a slider by using a method different from that of Japanese Patent Application No. 3-224751, that is, a sound wave. To do.

[0006]

The infusion device according to the present invention comprises a main body on which a syringe containing a drug solution is placed, a moving body for moving a sucker in the syringe, and a first and a second moving body. It is provided with a drive mechanism for moving at a predetermined speed between two positions, and a sonic distance meter provided with a sounding part and a sound receiving part that can be attached to the main body and the moving body, respectively.

The infusion device according to another embodiment has a main body on which a syringe containing a drug solution is mounted, a moving body for moving a sucker in the syringe, and first and second moving bodies.
It is provided with a drive mechanism for moving at a predetermined speed between the positions, a reflecting mirror attached to the moving body, and a sonic rangefinder having a sounding section and a sound receiving section which can be respectively attached to the main body.

According to still another aspect, the sonic range finder has an ultrasonic oscillator capable of supplying at least two kinds of ultrasonic frequencies to the sound producing section, and a second sound receiving section for receiving the sound at the installation location. And a discriminating section for discriminating the ultrasonic frequency component from the sound receiving section, and the ultrasonic wave which does not interfere with the sound at the installation location among the at least two kinds of ultrasonic frequencies based on the output of the discriminating section. And a switching unit that supplies a frequency to the sounding unit.

The sonic distance meter includes a thermometer for measuring the temperature of the installation site, a coefficient unit for obtaining a coefficient corresponding to the propagation speed of the sound wave based on the temperature of the thermometer, and a section from the sounding section to the sound receiving section. And a multiplier that multiplies the value corresponding to the arrival time by the coefficient.

The sonic rangefinder includes a pressure gauge for measuring the atmospheric pressure at the installation site, a second coefficient unit for obtaining a second coefficient corresponding to the propagation velocity of the sound wave based on the gauge pressure of the thermometer, and A second multiplier that multiplies a value corresponding to the arrival time from the sounding unit to the sound receiving unit by the second coefficient.

The sound producing unit produces a burst wave having a predetermined sound wave frequency component, the sound receiving unit receives the burst wave, and the sonic rangefinder counts at the start of the burst wave by the sound producing unit. For the first time, a counter is provided that stops counting when the envelope waveform of the burst wave by the sound receiving unit rises.

The sounding section produces a sweeping wave sweeping a predetermined sound wave frequency band, the sound receiving section receives the sweeping wave, and the sonic rangefinder detects the sweeping wave from the sounding section. A mixer that mixes the sweep wave from the sound receiving unit, rectifies the output of the mixer, and based on the specific sound wave frequency that is the maximum value of the rectified waveform, the moving distance of the sucker. And a distance detection unit for obtaining

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows an infusion device 1 according to an embodiment of the present invention.
Is shown. In the case 2 of the liquid transfusing device 1, an operating unit 4 for monitoring the liquid transfusing operation and the liquid transfusing state of the syringe 3 in which the drug solution is stored, and a mounting unit 5 to which the syringe 3 can be mounted
And are provided. Even if the syringe 3 is a standard product having a size of 50 mm, for example, the manufacturer has a different friction coefficient with the sucker and a different pressing force per unit flow rate. However,
Syringes of the same manufacturer with the same standard have almost no variation in the coefficient of friction, and therefore the coefficient of friction is substantially constant.

Further, the operation unit 4 includes a capacity indicator 6 for displaying the size of the mounted syringe 3 by, for example, an LED,
Centralized display 7 for displaying various operating states, infusion start indicator 8, infusion stop indicator 9, flow rate during infusion, cumulative flow rate or one-shot flow rate of ml / hr (hour) or ml A 4-digit numerical display 10 for displaying in units is arranged.

Therefore, the centralized display unit 7 has a built-in self-diagnosis display unit for instructing that the self-diagnosis program is in operation, and a closing / opening display unit that lights up when an abnormality occurs during infusion, such as blockage or detachment of the injection needle. A low voltage indicator that indicates that the secondary battery has reached the limit of use, an operation forgetting indicator that indicates a mistake in the operating procedure, and an infusion completion indicator that indicates infusion completion,
A standby indicator for indicating one minute before the completion of infusion is provided.

The operation portion 4 is further provided with a one-shot button 1 capable of sending a larger amount of infusion liquid than in normal infusion in an emergency.
1, an infusion amount button 12 for selecting the display content of the numerical display 10, an infusion start / stop button 13, a fast forward button 14, and a power button 15 are arranged. Furthermore, the numerical display 10
Above and below the flow rate setting button 1 that can set the flow rate for each digit
6 are arranged. These flow rate setting buttons 16 can be set between 0.0 and 199.9 ml per hour. Further, the sucker in the empty syringe 3 is pressed at a constant speed, the pressing force at this time is regarded as the pressing force loss value, and the learning function setting button 17 or the buzzer stop button ( (Not shown) is also arranged.

The mounting portion 5 includes a mounting portion 22 on which the outer cylinder 21 of the syringe 3 is mounted and a sucker 23 which slides inside the syringe 3.
A slider 24 that can be pressed to move from the first position to the second position, and as shown in FIG. 2, a drive mechanism 25 that drives the slider 24 in the mounting portion 22 direction (arrow a direction) while supporting the slider 24. Is equipped with. First, in the mounting portion 22, a holding portion 26 for fixing the mounted syringe 3 from above, and a syringe diameter detector 27 arranged below the holding portion 26.
And are provided. Further, the slider 24 has a drive mechanism 2
A release button 28 for releasing 5 and returning the slider 24 to the original position is provided. Further, the drive mechanism 25 moves the sucker 23 in the syringe 3 between the first position (transfusion start position) and the second position (transfusion end position) at a predetermined speed, and is connected to the slider 24. Part is bellows 29
It is covered with so that the inside cannot be seen.

Therefore, in the pump having the syringe 3 and the sucker 23, the syringe 3 is held by the holding portion 26 and the sucker 2 is held.
The rear end of the slider 3 contacts the slider 24. A flexible infusion pipe (not shown) communicating with the injection needle is connected to the tip of the syringe 3. Therefore, the syringe 3 is mounted on the mounting portion 22.
When the slider 24 is pushed by the drive mechanism 25 in the direction of the arrow a at a predetermined speed, the drug solution in the syringe 3 is pushed out at a predetermined flow rate and is passed through the infusion pipe and the injection needle. Injected into the patient.

The drive mechanism 25, as shown in FIG.
A main shaft 30 and a release shaft slidably supported by the frame 5a of the mounting portion 5 are provided. The main shaft 30 has one end fixed to the slider 24 and the other end fixed to the engaging member 32. On the other hand, the release shaft is arranged in parallel with the side opposite to the main shaft 30 and is not visible, but one end is pivotally supported by the slider 24, the other end is pivotally supported by the engaging member 32, and one end is released via an arm. It is fixed to the button 28 and the other end is fixed to an engaging claw (not shown) of the engaging member.

Like the slider 24, the engaging member 32 is slidably supported within the frame 5a of the mounting portion 5 and is reciprocally moved by the feed screw 34 that can engage with the engaging claw. That is, the engagement member 32 is provided with a guide rod (which is arranged on the front side of the feed screw 34, but not shown) and a feed rod which are arranged in parallel with the main shaft 30 and the release shaft in the frame 5a of the mounting portion 5. It is slidably attached to the screw 34. The feed screw 34 is axially supported by the frame 5a of the mounting portion 5 and is supported so as to be slightly movable in the axial direction. One end 34a contacts the pressure sensor 40, and the large gear 41 is fixed to the other end. The large gear meshes with a small gear fixed to the rotating shaft of a motor (not shown).

As shown in FIG. 2, an acoustic distance meter 50 is attached to the front side of the lower portion of the frame 5a of the mounting portion 5 as described above. The sound wave range finder 50 includes a sounding unit 51 attached to a moving body, that is, an engaging member 32, a sound receiving unit 52 attached to one end of a main body, that is, a driving mechanism, and the sound emitting unit 51 and the sound receiving unit 5.
2 and a CPU system for controlling 2. This CP
The U system is usually composed of a one-chip microcomputer system having a CPU, ROM, RAM, I / O port, timer, A / D converter and D / A converter or a normal microcomputer system.

The sound producing section 51 produces a burst wave having a predetermined sound wave frequency component, and the sound receiving section 52 receives the burst wave. Therefore, sonic rangefinder 5
As shown in FIG. 3, 0 is an ultrasonic oscillator 53 that oscillates at an ultrasonic frequency of, for example, 30 MHz, and a measurement clock CK having a frequency lower than this ultrasonic frequency, for example, 1 kHz, is input to the control terminal to generate the oscillator 53. A transmission gate 54 for converting the output of the above into a burst wave, and a power amplifier 55 for supplying the burst wave from this gate 54 to the sounding section 51. This measurement clock CK is I / O
It is supplied from the port defined in the output of the port.

The range finder 50 further includes a detector 56 for detecting or amplifying the burst wave input from the sound receiving unit 52, and a comparator for generating a pulse at the rising time of the output of the detector 56. 57 and a counter 58 for counting for the first time at the start of the burst wave by the sound generation unit 51 and for stopping counting at the rising time point of the envelope waveform of the burst wave by the sound reception unit 52. Therefore, as the counter 58, for example, a timer in the CPU system to which the basic clock of 10 MHz is input is used, and the counting of the basic clock is started at the rising time of the measurement clock, and at the time when the output pulse of the comparator 57 is input. Counting is stopped, an interrupt signal is sent to the CPU, and a program for transferring the value of the counter 58 to a predetermined RAM area is executed after the acknowledge of the CPU.

Such a sonic rangefinder 50 may malfunction due to disturbance, that is, construction noise generated near the installation site, noise of an automobile or train, and the count value may not indicate the original value. Therefore, it is important for the sonic rangefinder 50 to cover the inside of the device with a sound insulating material such as glass wool to insulate the sound.

Instead of this, the range finder 50 supplies at least two kinds of ultrasonic frequencies, that is, ultrasonic frequencies different from those of the ultrasonic oscillator 53, to the sound generator 51 through the second transmission gate 60. An ultrasonic auxiliary oscillator 61 to be obtained, a second sound receiving section 62 which is arranged outward and receives the sound of the installation location, and a discriminating section 63 which discriminates the ultrasonic frequency component from the sound receiving section 62, Based on the output of the discriminating unit, it is preferable to include a switching unit 64 that supplies, to the sound producing unit 51, an ultrasonic frequency that does not interfere with the sound at the installation location among at least two types of ultrasonic frequencies. Further, when an ultrasonic signal of the same phase is obtained from the sound receiving unit 52 and the second sound receiving unit 62 during the measurement period, the ultrasonic signal can be regarded as a disturbance, and therefore the measurement of the measurement period is performed. You may run a program that overrides the value.

The propagation velocity of sound waves in air changes depending on the temperature. Therefore, the sonic distance meter 50 receives a digital thermometer 66 for measuring the temperature of the installation place, a coefficient unit 67 for obtaining a coefficient corresponding to the propagation velocity of the sound wave based on the temperature of the thermometer 66, and the sound generator 51. A multiplier 68 for multiplying the value of the counter 56 (or a predetermined RAM area) corresponding to the arrival time to the sound section 52 by a coefficient is provided.

The digital thermometer 66 is connected to a coefficient ROM 67 in the CPU system which outputs a coefficient 1.00 when the temperature is 25.0 degrees C. In this coefficient ROM, the digital value corresponding to room temperature is input to the address end, and the corresponding digital value is obtained from the output end. The CPU system executes a multiplication program in which the multiplier 68 is emulated to correct the deviation of the propagation velocity of the sound wave in the air due to the temperature. Instead of this, a temperature-controlled heater may be provided in the device in order to keep the temperature between the sounding part and the sound receiving part in the device at, for example, 45 ° C. Of course, for example, 25 degrees C
A temperature controlled heater to obtain the temperature inside the device,
An electronic cooler may be provided.

The propagation velocity of sound waves in air also changes depending on the atmospheric pressure. Therefore, the sonic range finder 50 includes a digital pressure gauge 70 for measuring the atmospheric pressure at the installation location, and a second coefficient unit 71 for obtaining a second coefficient corresponding to the propagation velocity of the sound wave based on the gauge pressure of the pressure gauge. , Sound producing unit 51 to sound receiving unit 52
A second multiplier 72 for multiplying the value corresponding to the arrival time up to, that is, the output value of the multiplier 68 by the second coefficient.

That is, the digital pressure gauge 70 outputs a coefficient 1.00 when the gauge pressure is 0.00 mbar.
It is connected to the second coefficient ROM 71 in the PU system.
Therefore, the second coefficient ROM inputs the digital value corresponding to the atmospheric pressure to the address and obtains the coefficient corresponding to the atmospheric pressure, that is, the digital value. The CPU system includes a second multiplier 72
Is executed to correct the deviation of the propagation velocity of the sound wave in the air due to the atmospheric pressure. Therefore, the true distance from the sounding section 51 to the sound receiving section 52 is obtained from the second multiplier 72, and finally the moving distance of the sucker 23 is obtained as a digital value. This digital value is the CPU
It is sent to the infusion volume conversion circuit in the system.

In the previous embodiment, the sound producing section 51 to the sound receiving section 5
The distance between the ultrasonic waves up to 2 was calculated from the arrival time of the ultrasonic waves, but the interference phenomenon of the acoustic waves is used in the next embodiment. That is, the specific sound wave frequency signal supplied to the sound generator 51 is
When mixed with the reception signal from the sound receiving unit 52 that is separated by a certain distance, a correlation occurs between a specific sound wave frequency and a certain distance, and a peak occurs in the mixed wave.

Therefore, as shown in FIG. 4, the tone generator 51 is connected via a power amplifier 82 to a sweep oscillator 81 which oscillates a sweep wave capable of sweeping a predetermined sound wave frequency band. The digital frequency value set by the frequency register 83 under the PLL control is input to the sweep oscillator 81, and the sweep oscillator 81 sweeps from 400 Hz to 6,400 Hz, for example. The sweep time for one time is, for example, 10 depending on the supply amount of the infusion solution.
From 10 minutes to 10 hours is set. On the other hand, the sound receiving unit 52 receives the sweep wave and supplies it to the mixer 85 via the preamplifier 84.

The sweep wave from the sweep oscillator 81 is also input to the mixer 85 and mixed with the sweep wave from the sound receiving section 52. When the frequency of the sweep wave at this time corresponds to the distance between the sound producing section 51 and the sound receiving section 52, the output level of the mixer 85 becomes maximum. The output of the mixer 85 is the rectifier 86.
Is rectified by, is supplied to the A / D converter 87, and is converted into a digital level value. This digital level value is supplied to the register group of at least three columns of the maximum value detection circuit 88.

That is, the frequency register 83 sends the first digital frequency value to the sweep oscillator 81, sends the first digital level value to the register group of the first column after a predetermined time, and then the second digital value at the next cycle. The digital frequency value is sent to the sweep oscillator 81, the second digital level value is sent to the register group of the second column after a predetermined time, and the third digital frequency value is sent to the sweep oscillator 81, and after the predetermined time. When the digital level value of 3 is sent to the register group of the third column, and the contents of the register group of the second column are respectively larger than those of the first and third columns, the second digital frequency value is gated. It is supplied to the above-mentioned multipliers 68 and 72 via 89 to execute the above-mentioned multiplier routines respectively. The distance detection unit that obtains the moving distance of the sucker 23 based on the specific sound wave frequency that is the maximum value of the rectified waveform includes the maximum value detection circuit 88.

As shown in FIG. 5, the infusion device according to another embodiment includes a main body 5a on which the syringe 3 containing the drug solution is placed, and a moving body 32 for moving the sucker 23 in the syringe. , A drive mechanism 25 for moving the moving body between the first and second positions at a predetermined speed, a reflecting mirror 90 attached to the moving body 32, and a sounding section 5 attachable to the main body 5a.
1 and a sound wave range finder 50 having a sound receiving unit 52.
The sound producing portion 51 and the sound receiving portion 52 are attached to the printed circuit board 91 attached to the frame 5a of the attaching portion 5, while the reflecting mirror 90 is fixed to the moving body, that is, the engaging member 32. The sonic range finder 50 only doubles the measurement distance, and the configuration of the previous embodiment can be applied, so the description thereof will be omitted.

[0035]

As described above, since the liquid transfusing device according to the present invention uses the range finder utilizing ultrasonic waves or sound waves, the amount of liquid transfused during the liquid transfusing can be accurately grasped and the medicinal liquid is not wasted. Is obtained.

[Brief description of drawings]

FIG. 1 is an external perspective view showing an infusion device according to an embodiment of the present invention.

FIG. 2 is a partially cutaway sectional view of the infusion device of FIG.

FIG. 3 is a block diagram of an acoustic distance meter according to the present invention.

FIG. 4 is a block diagram of another sonic rangefinder according to the present invention.

FIG. 5 is a partially cutaway front view of an infusion device according to another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Infusion device 3 Syringe 25 Drive mechanism 50 Sonic distance meter 51 Sounding unit 52 Sound receiving unit 53 Ultrasonic oscillator 54 Transmission gate 56 Detector 57 Comparator 58 Counter

Claims (12)

[Claims] 1. A main body on which a syringe containing a drug solution is placed, a moving body for moving suckers in the syringe, and the moving body is moved at a predetermined speed between first and second positions. An infusion device comprising: a drive mechanism; and a sonic distance meter having a sounding part and a sound receiving part that can be attached to the main body and the moving body, respectively. 2. The sonic rangefinder comprises: an ultrasonic oscillator capable of supplying at least two kinds of ultrasonic frequencies to the sound producing section; a second sound receiving section for receiving sound at a place of installation; A discriminating section for discriminating ultrasonic frequency components from the section, and based on the output of the discriminating section, the ultrasonic frequency which does not interfere with the sound at the installation place among the at least two kinds of ultrasonic frequencies The infusion device according to claim 1, further comprising a switching unit that supplies the liquid to the infusion device. 3. The sonic distance meter, a thermometer for measuring the temperature of an installation site, a coefficient unit for obtaining a coefficient corresponding to the propagation speed of a sound wave based on the temperature of the thermometer, and a sound receiving unit for receiving sound. The infusion device according to claim 1, further comprising: a multiplier that multiplies a value corresponding to an arrival time to a part by the coefficient. 4. The sonic distance meter comprises a pressure gauge for measuring the atmospheric pressure at the installation location, and a second coefficient unit for obtaining a second coefficient corresponding to the propagation velocity of the sound wave based on the gauge pressure of the thermometer. The infusion device according to claim 1, further comprising: a second multiplier that multiplies a value corresponding to an arrival time from the sounding unit to the sound receiving unit by the second coefficient. 5. The sound producing unit produces a burst wave having a predetermined ultrasonic frequency component, the sound receiving unit receives the burst wave, and the sonic distance meter produces a burst wave of the burst wave produced by the sound producing unit. The infusion device according to claim 1, further comprising a counter that stops counting at a rising time point of an envelope waveform of the burst wave by the sound receiving unit for the first time after counting at the start. 6. The sound producing section produces a sweeping wave sweeping a predetermined sound wave frequency band, the sound receiving section receives the sweeping wave, and the sound wave rangefinder is provided with the sweeping wave from the sound producing section. And a mixer that mixes the sweep wave from the sound receiving unit, rectifies the output of the mixer, and based on the specific sound wave frequency that is the maximum value of this rectified waveform, The infusion device according to claim 1, further comprising a distance detector that obtains a moving distance. 7. A main body on which a syringe containing a drug solution is placed, a moving body for moving suckers in the syringe, and the moving body is moved at a predetermined speed between first and second positions. An infusion device comprising: a drive mechanism; a reflecting mirror attached to the moving body; and a sonic distance meter having a sounding unit and a sound receiving unit that can be attached to the main body. 8. The sonic rangefinder comprises: an ultrasonic oscillator capable of supplying at least two kinds of ultrasonic frequencies to the sound producing section; a second sound receiving section for receiving sound at an installation location; A discriminating section for discriminating ultrasonic frequency components from the section, and based on the output of the discriminating section, the ultrasonic frequency which does not interfere with the sound at the installation place among the at least two kinds of ultrasonic frequencies The infusion device according to claim 7, further comprising a switching unit that supplies the liquid to the. 9. The sonic distance meter comprises a thermometer for measuring the temperature of an installation site, a coefficient unit for obtaining a coefficient corresponding to the propagation velocity of a sound wave based on the temperature of the thermometer, and a sound receiving unit for receiving sound. The infusion device according to claim 7, further comprising: a multiplier that multiplies a value corresponding to an arrival time to a part by the coefficient. 10. The sonic rangefinder comprises: a pressure gauge for measuring the atmospheric pressure at the installation site; and a second coefficient unit for obtaining a second coefficient corresponding to the propagation velocity of the sound wave based on the gauge pressure of the thermometer. The infusion device according to claim 7, further comprising: a second multiplier that multiplies a value corresponding to an arrival time from the sounding unit to the sound receiving unit by the second coefficient. 11. The sound producing unit produces a burst wave having a predetermined ultrasonic frequency component, the sound receiving unit receives the burst wave, and the sound wave rangefinder outputs the burst wave generated by the sound producing unit. The infusion device according to claim 7, further comprising a counter that stops counting at a rising time point of the envelope waveform of the burst wave by the sound receiving unit for the first time after counting at the start. 12. The sound producing unit produces a sweeping wave sweeping a predetermined sound wave frequency band, the sound receiving unit receives the sweeping wave, and the sound wave rangefinder has the sweeping wave from the sound producing unit. And a mixer that mixes the sweep wave from the sound receiving unit, rectifies the output of the mixer, and based on the specific sound wave frequency that is the maximum value of this rectified waveform, The infusion device according to claim 7, further comprising a distance detector that obtains a moving distance.