JPS63221221A - Tube body for measurement of ultrasonic fluid information - Google Patents

Abstract

PURPOSE:To mount a probe for flow rate measurement on a tube body where fluid to be measured flows without mistaking its position by forming a recessed part where the probe is fitted in the outer peripheral surface of the tube body. CONSTITUTION:An ultrasonic flowmeter 10 measures the flow rate of extracted blood so as to control the driving state of a pump 20 for an auxiliary heat. The probe 14 for fluid measurement is fitted to the tube where blood to be measured flows, i.e., a part where blood extraction canula 12 is mounted. Here, the recessed part 12a is formed at the part of the tube 12 at the mounted part, so a mounting person only presses the part between the tip parts of a couple of gripping pieces 24d of the probe main body 14 against the tube 1 where the recessed part 12a is formed to securely mount the probe without mistaking its position.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention relates to an ultrasonic flowmeter that uses ultrasonic waves to measure the flow velocity in a pipe and uses this measured value for monitoring or control. The present invention relates to a tube used for measuring ultrasonic fluid information.

[Prior Art] Conventionally, when measuring the flow velocity or flow rate of a fluid to be measured flowing inside a pipe using ultrasonic waves, a probe such as an ultrasonic flowmeter is fixed to the outer wall of the pipe. In addition, in recent years, progress has been made in the development of artificial heart-lung machines, auxiliary hearts, or artificial heart devices to supplement or temporarily replace the heart or cardiopulmonary functions outside the body during surgical procedures or other surgeries. There is. In actual treatment, such a heart-lung machine, an auxiliary heart, or an artificial heart device,
It has also been effective in clinical applications for patients.

In such clinical applications, blood flow measurement is particularly important.
An important monitoring element, ultrasonic flowmeters are important in that they allow flow measurements without direct contact with blood.
It is said to be effective.

[Problems to be Solved by the Invention] When using such an ultrasonic flowmeter, the probe may be attached to the outer wall of the pipe using an adhesive, or the probe may be attached to the outer wall of the pipe using a band or a special holder. Must be fixed;
If the mounting position is incorrect, the recovery operation will be extremely troublesome. Furthermore, if the tube is thick, the ultrasonic waves will be absorbed by the tube wall and attenuated, which may deteriorate measurement accuracy. In particular, in order to prevent the measurement accuracy from decreasing due to attenuation of the ultrasonic waves, it is necessary to increase the ultrasonic output, which is undesirable because it is accompanied by an increase in cost.

This invention was made in view of the above-mentioned problems.
An object of the present invention is to provide an ultrasonic fluid information measuring tube that can clearly indicate the mounting position of a measuring probe and can improve measurement accuracy.

[Means for Solving the Problems] In order to solve the above-mentioned problems and achieve the purpose, an ultrasonic fluid information measuring pipe according to the present invention is a pipe in which a fluid to be measured flows. , is characterized by having a recess formed on the outer peripheral surface of the tubular body into which a flow velocity measuring probe of an ultrasonic fluid information measuring device is fitted.

According to the first embodiment of the tube for ultrasonic fluid information measurement according to the present invention, the thickness of the portion of the tube where the recess is provided is smaller than the thickness of other portions of the tube. It is characterized by

According to the second embodiment of the tube for ultrasonic fluid information measurement according to the present invention, the thickness of the portion of the tube in which the recess is provided is set to 0.3 to 0.7 mm. It is characterized by things.

According to the third embodiment of the ultrasonic fluid information measuring tube according to the present invention, the bottom surface of the recess is formed of a curved surface, and the thickness of the portion of the tube in which the recess is provided is a predetermined thickness. It is characterized by being kept at a constant value.

According to the fourth embodiment of the tube for ultrasonic fluid information measurement according to the present invention, the bottom surface of the recess is formed of a flat surface, and the thickness of the portion of the tube in which the recess is provided is variable. It is characterized by

[Function] In the tube for ultrasonic fluid information measurement configured as described above, when attaching the probe to the outer wall of the tube, the recess formed in the probe can be targeted, and the attachment position can be manipulated. There is no possibility of someone making a mistake. In addition, by providing this recess, the thickness of the part of the tube where this recess is provided is
It will be reduced. Therefore, the ultrasonic waves passing through the reduced thickness portion are less likely to be attenuated, resulting in improved measurement accuracy.

[Example] The configuration of an example in which the ultrasonic fluid information measuring tube according to the present invention is applied to a tube used in an ultrasonic flow meter will be described in detail below with reference to the accompanying drawings. explain.

As shown in FIG. 1, the ultrasonic flowmeter 10 is removably attached to the outer wall of a tube 12 through which blood as a fluid to be measured flows. A probe 14 that detects the flow velocity of the
and a calculation device 18 that is electrically connected to the probe 14 via a cable 16 and calculates the flow rate of blood flowing in the tube 12 based on the flow velocity detected by the probe 14.
It is equipped with

In one embodiment, the probe 14 is used to measure the blood flow rate in a blood circuit for a heart assisting heart, and a blood removal cannula that sends blood from the patient to a pump 20 for the heart assisting heart is connected to the pump 20. , is used as the tube 12 through which the blood as the fluid to be measured flows. Incidentally, a blood feeding cannula 22 is attached to this auxiliary heart pump 20 for returning the energized blood to the patient.

The above-described probe 14 includes a probe body 24 that is detachably attached to the outer wall of the tube 12 through which blood as the fluid to be measured flows, as shown in different cross sections in FIGS. 2A and 2B. This probe body 24
There is an ultrasonic transmitter 26a fixed in the base 24a of the probe body 24, which outputs ultrasonic waves toward the blood flowing in the tube 12, and an ultrasonic transmitter 26a that receives ultrasonic waves reflected from the flowing blood. and an ultrasonic receiver 26b for detecting data regarding flow velocity, with their axes intersecting each other. One end of the cable 16 described above is connected to the ultrasonic transmitter 26a and the ultrasonic receiver 26b, respectively.

These ultrasonic transmitter 26a and ultrasonic receiver 26b constitute a detection mechanism 26 that detects data regarding flow velocity. The detection mechanism 26 is mounted on a base 24b made of acrylic resin within the base 24a.

Moreover, as is clear from FIG. 2B, the tube 1 of the base 24a
The portion facing the outer wall of the tube 2 is formed to protrude in a planar rectangular shape toward the portion of the tube 12 to which it is attached. A recess 24c is formed on the surface of the protruding portion of the base 24a, in which the base 24b is housed with the detection mechanism 26 attached thereto.

Moreover, as is clear from FIG. 2A, the probe body 24
are integrally formed with the base 24a, and are spaced apart from each other in order to grip the outside/wall of the tube 12 from both sides to prevent the base 24a from falling off the tube 12. A pair of gripping pieces 24d are provided. The probe body 24 including these gripping pieces 24d is made of urethane rubber as an elastic body.

Note that the distance between the pair of gripping pieces 24d at the distal ends is set to be smaller than the diameter of the tube 12, and the distance at the middle portion thereof is set to be approximately the same as the diameter of the tube 12. In this way, with the probe 14 attached,
This attached state is maintained, and when attached, since the pair of gripping pieces 24d are made of an elastic material, their tips are opened and can be easily attached to the outer wall of the tube 12. It is configured to be grasped.

Here, in this embodiment, the inner surfaces of the base 24a and the pair of gripping pieces 24d are set to be continuous, and are formed in a shape corresponding to the outer wall of the tube 12.

That is, the probe main body 24 is formed into a substantially C-shape as a whole. In this way, the probe 14
As shown in FIG. 2A, the inner surface of the base 24a and the pair of gripping pieces 24d is a tube! 2, and the attached state is reliably maintained by mutual frictional engagement.

On the other hand, the blood removal cannula as the tube 12 to which such a probe 14 is attached is made of a commercially available vinyl chloride resin. A recess 12a is formed in which the protruding portion of the probe 14 is fitted. This attached portion is set on the side of the pipe 12 that is close to the pump 20. This recess 12a has the function of clearly indicating the mounting position of the probe 14, and the wall thickness of the tube 12 is reduced by the amount by which the recess 12a is formed, so that it has the minimum thickness t. This serves to reduce the attenuation of the ultrasonic waves emitted from the ultrasonic transmitter 26a.

Here, the minimum thickness t is set from the viewpoint of the accuracy of forming the recess 12a and the attenuation rate of ultrasonic waves, and in this embodiment, it is 0.5±0.21. That is, this thickness t is set within a range of a maximum of 0.7 mm and a minimum of 0.3 mm.

Note that this thickness t is constant in all parts, as shown in Figure 's3. In other words, the bottom surface of the recess 12a is composed of a curved surface along the inner circumferential surface of the tube 12, and
The lower surface of the protrusion formed on the base 24a of the probe body 24 is also formed of a curved surface along the inner peripheral surface of the tube 12.

In the ultrasonic flowmeter 10 configured as described above, the operation using the probe 14 for measuring flow velocity will be explained.

When an auxiliary heart is used in the surgical procedure of interest, the flow rate of blood removed is measured by the ultrasonic flow meter 10 in order to control the driving state of the pump 20 for the auxiliary heart. In this measurement, first, the recess 1 of the tube 12 is
A jelly-like liquid is applied to the bottom surface of the probe body 2a in advance in order to prevent air or bubbles from entering between the probe body 2a and the probe body 14, thereby increasing the attenuation of the ultrasonic waves. After applying this jelly, the probe 14 for flow velocity measurement is inserted into the tube through which blood as the fluid to be measured flows, that is, the blood removal cannula 1.
2, it is fitted into the attached part.

Here, there is a recess 12 in the part of the tube 12 at this mounting position.
a is formed, the operator can reliably and easily recognize the mounting position without making a mistake. Furthermore, the mounting operation can be accomplished by simply pressing the tip portions of the pair of gripping pieces 24d, which are spaced apart from each other, of the probe main body 24, which has a C-shaped cross section, against the tube 12.

That is, since the pair of gripping pieces 24d are made of an elastic body, the distance between their tips is set to be smaller than the diameter of the tube 12, but as the pressing operation progresses, these gripping pieces 24d The piece 24d will open outward. Thereafter, when the tip passes through the diameter portion of the tube 12, it is closed again by the elastic return force of the gripping piece 24d, resulting in the state shown in FIG. 2A. In this way, the probe 14 is reliably gripped on the outer wall of the tube 12, and this gripping state is maintained well.

Thereafter, by starting the operation of the arithmetic device 18, ultrasonic waves are emitted from the ultrasonic transmitter 28a of the detection mechanism 26 as continuous waves of, for example, 5 MHz. The ultrasonic waves thus emitted are reflected by the blood flowing in the tube 12, and the reflected ultrasonic waves are received by the ultrasonic receiver 26b with different frequencies due to the Doppler effect. .

The data regarding the flow velocity received by the ultrasonic receiver 26b is sent to the arithmetic unit 18 via the cable 16, where the information is processed and the flow rate of blood flowing in the tube 12 is calculated. be done.

After the blood flow rate has been measured in this manner and the surgical procedure of interest has been completed, the probe 14 is removed from the tube 12 and the series of measurement operations is completed. After this, the thickness t of the recess 12a formed in the tube 12 is set to be extremely thin, so in order to protect it, the dummy probe 2 is
B is attached to the attached portion of the tube 12 as shown in FIG.

As described in detail above, according to this embodiment, the probe 14 for measuring the flow velocity is formed from an elastic material and has a substantially C-shaped cross section, so that the attached state of the probe 14 can be maintained well and The operation of attaching the probe 14 is extremely simplified, and the operating time is also shortened. In this way, even if it becomes necessary to urgently measure the flow rate, by using this probe 14, it becomes possible to deal with the problem reliably.

Further, according to this embodiment, since the recess 12a is formed in the attachment portion of the tube 12 to which the probe 14 is attached, the operator will not be able to erroneously attach the probe 14 to the attachment position. In addition, by forming the recess 12a in the tube 12, the thickness of the tube 12 at this attached portion is set to be extremely thin, and therefore the attenuation of the ultrasonic waves used for measurement can be suppressed well, resulting in measurement accuracy. will improve.

Furthermore, since the cannula is generally tapered, if the probe 14 is not attached to the portion of the cannula that corresponds to the inner diameter of the probe 14, the probe 14 may become loose and become loose.
However, according to this embodiment, since the mounting position is clearly indicated by the recess 12a, such a risk can be completely eliminated. become.

It goes without saying that this invention is not limited to the configuration of the one embodiment described above, and can be modified in various ways without departing from the gist of the invention.

For example, in one embodiment described above, the recess 12a formed in the tube 12 is as shown in FIG.
Although the thickness of the portion of the tube 12 where the portion a is provided is constant, the thickness is not limited to such a configuration, and as shown in FIG. 5 as a modified example, the bottom surface of the recess 12b The minimum thickness of the pipe 12 set by providing the recess 12b may be defined as the thickness t as described above.The recess 12b is set in this way. This achieves the effect that the operation of forming the recess 12b is simplified.

Further, in the above-described embodiment, the tube 12 in which the recess 12a is formed is described as being composed of a blood removal cannula, but the structure is not limited to this, and other structures as shown in FIG. As shown as a modified example of the blood feeding cannula 2
A recess 22a may be formed in 2. In short, this recess is set anywhere as long as the fluid to be measured flows.

[Effects of the Invention] As detailed above, the ultrasonic fluid information measurement tube according to the present invention is a tube through which a fluid to be measured flows, and is formed on the outer peripheral surface of the tube. It is characterized by having a recess into which a flow velocity measuring probe of a sonic fluid information measuring device is fitted.

Therefore, according to the present invention, there is provided an ultrasonic fluid information measuring tube that can clearly indicate the mounting position of the measurement probe and can improve measurement accuracy.

[Brief explanation of drawings]

FIG. 1 is a perspective view schematically showing the configuration of a flow velocity measuring probe to which an embodiment of the ultrasonic fluid information measuring tube according to the present invention is applied, and an ultrasonic flow meter using the probe; FIG. 2A; Figure 2B is a cross-sectional view showing how the probe is attached to the tube, taken at different cutting planes; Figure 3 is a cross-sectional view of the tube showing the shape of the recess; Figure 4 is how the dummy probe is attached. FIG. 5 is a sectional view showing a modified example of the recess; and FIG. 6 is a front view showing another modified example of the setting position of the recess. In the figure, 10... Ultrasonic flow meter, 12... Tube (blood removal cannula), 12a'' recess, 14... Probe for flow velocity measurement, 16... Cable, 18... Arithmetic device ,2
0...Pump, 22...Blood feeding cannula, 22a.
...Recess, 24 ...Probe body, 24 a...
・Base, 24b... Mounting is on stand, 24c... Recess, 2
4 d-...Gripping piece, 26...Detection mechanism, 26a...
・Ultrasonic transmitter, 26b...Ultrasonic receiver, 28...
・It is a dummy probe. Figure 1, Figure 2A, Figure 2, Figure 1, Figure 3, Figure 1g, Figure 5, Figure 4

Claims (5)

[Claims] (1) A pipe body through which a fluid to be measured flows, characterized by having a recess formed on the outer peripheral surface of the pipe body into which a flow velocity measurement probe of an ultrasonic fluid information measuring device is fitted. A tube body for ultrasonic fluid information measurement. (2) The ultrasonic fluid according to claim 1, wherein the thickness of the portion of the tube where the recess is provided is smaller than the thickness of other portions of the tube. Tube body for information measurement. (3) The thickness of the portion of the tube where the recess is provided is 0.
The tube body for ultrasonic fluid information measurement according to claim 2, wherein the tube body is set to 3 to 0.7 mm. (4) The bottom surface of the recess is composed of a curved surface, and the thickness of the portion of the pipe body in which the recess is provided is kept constant at a predetermined value. The tube body for ultrasonic fluid information measurement according to item 2. (5) According to claim 2 or 3, the bottom surface of the recess is made of a flat surface, and the thickness of the portion of the tube in which the recess is provided varies. Tube body for ultrasonic fluid information measurement.