JP2005261858A - Corrugated tube for respiration circuit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a corrugated tube for a respiration circuit (a respiration tube) capable of reducing the cost while maintaining the safety. <P>SOLUTION: Hot water is fed into a first channel 50 from an end of the channel. The fed hot water reaches an end on the downstream side of the first channel 50 (the center right end in the figure), where the hot water enters a second channel 60, then returns to the original position. During the period, the hot water heats a wall surface of an internal tube 10 while spirally moving between the internal tube 10 and an external tube 20. Decline of temperature of expired air or inspired air inside the corrugated tube can be prevented by the heating. Furthermore, if an electric wire 70 is electrified, the generated heat can also prevent the decline of temperature of expired air or inspired air inside the corrugated tube. Even if the electric wire 70 is overheated, part of the heat can be absorbed in the hot water in the channels. In addition, by detecting the quantity of returned hot water, a breakage in the corrugated tube can be detected. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a serpentine tube for a breathing circuit.

  An example of a conventional breathing circuit (ventilator) is shown in FIG. This breathing circuit includes a pump device 1, a breathing tube 2, and a mouthpiece (so-called Y piece) 3. The respiratory tube 2 includes an inspiratory tube 2a and an expiratory tube 2b.

  According to this device, the intake air sent from the pump device 1 can be supplied to the subject via the intake pipe 2 a and the mouthpiece 3. On the other hand, exhaled air sent from the subject is collected by the pump device 1 through the mouthpiece 3 and the exhalation tube 2b. Various snake pipes are used as the inspiratory pipe 2a or the expiratory pipe 2b.

  In this apparatus, the intake air sent from the pump apparatus 1 is usually adjusted to a temperature of 35 ° C. and a humidity of 100%. Moreover, the exhaled air sent out from the subject usually has a temperature of 37 ° C. and a humidity of 100%. For this reason, when the breathing circuit is at room temperature, condensation occurs inside the inspiratory pipe 2a and the expiratory pipe 2b due to a decrease in the temperature of the inspiratory or expiratory air. It is necessary to avoid water generated by condensation from entering the subject. Therefore, conventionally, the water trap 4 is attached in the middle of the inspiratory pipe 2a and in the middle of the expiratory pipe 2b. The water trap 4 has a flow path for discharging water in the pipe to the outside.

  However, in the conventional breathing circuit, the inside and outside of the respiratory tube 2 are connected via the water trap 4. Therefore, in the conventional breathing circuit, consideration must be given to prevent the intake air from being contaminated by the outside air.

  In order to avoid this problem, as described in Patent Document 1 below, for example, a device for attaching a heater (heating wire) along the respiratory tube 2 has been proposed. According to this device, the respiratory tube 2 is heated by Joule heat to prevent a decrease in the tube temperature and prevent condensation. In this way, installation of the water trap can be omitted.

However, in such a technique, since a heating wire is used as the heating means, if an excessive current flows through the heating wire, the respiratory tract may be overheated and dissolved. Therefore, conventionally, the heating temperature is controlled using a sensor or a control device. If this control is inaccurate, the heating wire may be overheated, so this control needs to be performed accurately and reliably. For this reason, the conventional apparatus has the fault of becoming expensive.
Japanese Patent Laid-Open No. 6-23051

  The present invention has been made based on the above circumstances, and an object of the present invention is to provide a snake tube (breathing tube) for a breathing circuit that can realize low cost while maintaining safety.

  The serpentine tube according to the present invention includes an inner tube, an outer tube, a first rib, and a second rib. The inner pipe is inserted inside the outer pipe and extends in substantially the same direction as the outer pipe. The first rib and the second rib are arranged between the inner tube and the outer tube, and are circulated so as to form a double spiral. A first flow path and a second flow path are formed between the inner tube and the outer tube by the rotated first rib and second rib. The first flow path and the second flow path are communicated so that the fluid flowing through one of them returns from the other.

  An electric wire for heating may be disposed on the first rib or the second rib.

  The heating electric wire may include a first electric wire body and a second electric wire body. The first electric wire body may be disposed on one of the first rib and the second rib, and the second electric wire body may be disposed on the other. You may electrically connect the said 1st electric wire body and the 2nd electric wire body in the edge part vicinity of the said inner cylinder or an outer cylinder.

  An electric wire for heating may be disposed on one of the first rib or the second rib, and a thermocouple may be disposed on the other.

  A thermocouple may be disposed on the first rib or the second rib.

  The electric wire may be disposed inside the first rib or the second rib.

  The thermocouple may be disposed inside the first rib or the second rib.

  The breathing circuit according to the present invention includes any one of the above-described serpentine tubes.

  ADVANTAGE OF THE INVENTION According to this invention, the serpentine tube for breathing circuits which can implement | achieve low cost, maintaining safety | security can be provided.

(First embodiment)
Hereinafter, a breathing tube for a breathing circuit according to a first embodiment of the present invention will be described with reference to FIGS. In description of this embodiment, about the structure which is common in the above-mentioned conventional breathing circuit, description is simplified using the same code | symbol.

  The serpentine tube of the present embodiment mainly includes an inner tube 10, an outer tube 20, a first rib 30, a second rib 40, a first channel 50, a second channel 60, and an electric wire 70. As an element. The material of the inner tube 10, the outer tube 20, the first rib 30 and the second rib 40 is, for example, polyethylene, but is not limited thereto.

  Both the inner tube 10 and the outer tube 20 are formed in a cylindrical shape. The inner tube 10 has a smaller diameter than the outer tube 20 and is inserted inside the outer tube 20. In this state, the inner tube 10 is substantially coaxial with the outer tube 20. Further, the inner tube 10 is extended in substantially the same direction as the outer tube 20. A gap is formed between the inner tube 10 and the outer tube 20.

  The 1st rib 30 and the 2nd rib 40 are arrange | positioned between the inner tube | pipe 10 and the outer tube | pipe 20, and are circulated so that two spirals may be formed. In FIG. 2, the 1st rib 30 is shown with the white circle, the 2nd rib 40 is shown with the black circle, and those extended states are each shown with the broken line. In this embodiment, the first rib 30 and the second rib 40 are parallel. That is, the distance between the two is constant. In this embodiment, the first rib 30 and the second rib 40 have a substantially circular cross section.

  The first flow path 50 and the second flow path 60 are formed between the inner tube 10 and the outer tube 20 by the first rib 30 and the second rib 40 that are circulated in this manner. Accordingly, the first flow path 50 and the second flow path 60 also circulate between the inner tube 10 and the outer tube 20 so as to form two spirals.

  The first flow path 50 and the second flow path 60 are communicated so that the fluid flowing through one of them returns from the other. For example, as shown in FIG. 2, the end of the first flow path 50 (the right end in FIG. 2) is connected to the end of the second flow path 60 (the right end in FIG. 2), so that the sent fluid returns. It is configured. Of course, the end surfaces (the end surface on the right side in FIG. 2) of the inner cylinder 10 and the outer cylinder 20 are closed so that the hot water does not leak to the outside.

  The electric wire 70 includes a first electric wire body 71 and a second electric wire body 72 (see FIGS. 3 and 4). Each of these electric wire bodies 71 and 72 is made of a conductor (for example, nichrome wire) that can be used for resistance heating. The 1st electric wire body 71 is arrange | positioned inside the 1st rib 30 (substantially axial center position) (refer FIG. 3). Similarly, the 2nd electric wire body 72 is arrange | positioned inside the 2nd rib 40 (substantially axial center position) (refer FIG. 4). Thereby, in this embodiment, the electric wire 70 for a heating is arrange | positioned at each rib 30 and 40. As shown in FIG.

  The first electric wire body 71 and the second electric wire body 72 are electrically connected in the vicinity of the end of the inner cylinder 10. Although the specific means for that is arbitrary, for example, the first rib 30 and the second rib 40 are connected to each other at the end of the inner cylinder 10 (the right end in FIG. 1). The electric wire body 71 and the second electric wire body 72 can be connected.

  The serpentine tube 1 configured as described above can be used as a respiratory tube for a respiratory circuit, as in the conventional case. When the serpentine tube of the first embodiment is used, it is preferable to use a control unit 8 as shown in FIG. The control unit 8 includes a water supply unit 81 and an energization unit 82 in addition to the pump 1 shown in FIG.

  The water supply unit 81 is connected to the first flow path 50 and the second flow path 60, sends hot water to one of these, and collects hot water returning from the other. Since the concrete design of such a water supply part 81 is easy for those skilled in the art, detailed description is abbreviate | omitted.

  The energization part 82 is electrically connected to the first electric wire body 71 and the second electric wire body 72 and energizes them.

(Operation of the first embodiment)
Next, an example of the operation of the serpentine tube according to the present embodiment will be described. First, warm water is fed into the inside from the end of the first flow path 50. The temperature of the hot water is preferably high enough to prevent dew condensation inside the serpentine tube. The temperature of the hot water is considered to be preferably equal to or higher than the body temperature (for example, 40 ° C. or higher). It is considered that the upper limit of the hot water temperature is sufficient if it does not cause the subject to burn. For example, it is considered that the temperature is preferably 60 ° C. or lower.

  The hot water fed into the first flow path 50 reaches the end portion on the downstream side of the first flow path 50 (the right end portion in FIG. 2), enters the second flow path 60, and passes through the second flow path 60. To return to the water supply unit 81. Meanwhile, the hot water warms the wall surface of the inner tube 10 while moving spirally between the inner tube 10 and the outer tube 20.

  In the serpentine tube of this embodiment, this warming can prevent a decrease in the temperature of exhaled air or inhalation inside the serpentine tube. Thereby, it becomes possible to prevent dew condensation in the serpentine tube.

  Furthermore, in the serpentine tube of the present embodiment, the warm water sent out drops in the path and returns to its original state. At this time, since the going hot water and the returning hot water are adjacent to each other, temperature exchange occurs between them. For this reason, in the serpentine tube of this embodiment, the temperature gradient can be made gentle as the entire serpentine tube. When the temperature gradient is steep, it is necessary to manage the humidity assuming the lowest temperature, and at a high temperature, the humidity becomes low, making actual control extremely difficult. In this embodiment, by making the temperature gradient of the entire serpentine gentle, it becomes easy to control the humidity in the serpentine, and it is possible to prevent condensation more effectively.

  Further, in the serpentine tube of this embodiment, the electric wire 70 is energized. The time for energization is preferably after warm water is fed, but is not limited thereto. When the electric wire 70 is energized, the electric wire 70 is heated by resistance and generates heat. In the present embodiment, this heat generation can also prevent a decrease in the temperature of exhalation or inhalation inside the snake tube and prevent condensation in the snake tube.

  Further, in the present embodiment, since the first flow path 50 and the second flow path 60 are adjacent to the first rib 30 and the second rib 40, even if the electric wire 70 is overheated, A part can be absorbed by the hot water in the flow path.

  In addition, in this embodiment, since warm water is in contact with almost the entire surface of the first rib 30 and the second rib 40, the amount of heat absorbed by the warm water is considerably large. Therefore, this serpentine tube has an advantage that the serpentine tube is not easily damaged even if the electric wire 70 is overheated, and safety is further improved.

  Moreover, in this embodiment, since the electric wire 70 is arrange | positioned inside the 1st and 2nd ribs 30 and 40, it is hard to produce the short circuit of the electric wire 70, and there also exists an advantage that safety is high also from this point.

  Furthermore, in this embodiment, since the warm water sent into the first flow path 50 returns from the second flow path 60, the amount of warm water returning from the second flow path 60 is reduced if the serpentine tube is damaged. To do. If the amount of warm water returning through the second flow path 60 is detected, it is possible to detect the presence or absence of breakage of the serpentine tube.

  In the first embodiment, hot water is sent from the first flow path 50, but it is also possible to use hot water from the second flow path 60 and return the hot water through the first flow path 50.

  Further, in the first embodiment, two ribs are formed to form two spirals, but three or more spirals are formed using three or more ribs, and hot water is formed using a flow path formed in them. May be supplied or recovered.

(Second Embodiment)
Next, a second embodiment of the serpentine tube according to the present invention will be described with reference to FIG. In this embodiment, the first electric heating body 71 and the second electric heating body 72 of the electric wire 70 are arranged substantially parallel to only one of the first rib 30 or the second rib 40 (the first rib 30 in the illustrated example). Yes. In this embodiment, no electric heating element is arranged on the other rib (not shown).

  In the configuration of the second embodiment, the same advantages as those of the first embodiment can be obtained. Since other configurations and advantages are the same as those of the first embodiment, detailed description thereof is omitted.

(Third embodiment)
Next, a third embodiment of the serpentine tube according to the present invention will be described with reference to FIG. In this embodiment, the same components as those in the second embodiment are denoted by the same reference numerals, description thereof is omitted, and only different portions are described.

  In the third embodiment, a thermocouple 80 is disposed on the other of the first rib 30 or the second rib 40 (second rib 40 in the illustrated example). The thermocouple 80 is composed of two metal wires. The tip of the thermocouple 80 (the connection point of the two metal wires) is near the tip of the serpentine tube.

  According to the third embodiment, the temperature of the serpentine tube (for example, the temperature at the tip of the serpentine tube) can be measured relatively accurately by the thermocouple 80. Thereby, there exists an advantage that the overheating and temperature fall of a snake tube can be detected, and safety can be improved further. Other configurations and advantages are the same as those of the second embodiment, and thus description thereof is omitted.

  Note that the description of each of the embodiments is merely an example, and does not indicate a configuration essential to the present invention. The configuration of each part is not limited to the above as long as the gist of the present invention can be achieved.

  According to the present invention, it is possible to provide a snake tube that can be used as a respiratory tube for a respiratory circuit (respirator).

It is explanatory drawing of the conventional breathing circuit. It is sectional drawing of the principal part along the axial direction of the snake tube in 1st Embodiment of this invention. FIG. 3 is an enlarged view of a main part of FIG. 2. FIG. 3 is an enlarged view of a main part of FIG. 2. It is a block diagram which shows an example of the control part for using the snake tube of FIG. It is explanatory drawing of 2nd Embodiment of this invention, Comprising: It is a figure of the part corresponded in FIG. It is explanatory drawing of 3rd Embodiment of this invention, Comprising: It is a figure of the part corresponded in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Inner pipe 20 Outer pipe 30 1st rib 40 2nd rib 50 1st flow path 60 2nd flow path 70 Electric wire 71 1st electric wire body 72 2nd electric wire body 80 Thermocouple 9 Control part 91 Water supply part 92 Current supply part

Claims (8)

An inner tube, an outer tube, a first rib, and a second rib;
The inner tube is inserted inside the outer tube and extends in substantially the same direction as the outer tube;
The first rib and the second rib are arranged between the inner tube and the outer tube, and are circulated so as to form a double spiral,
A first flow path and a second flow path are formed between the inner pipe and the outer pipe by the rotated first rib and second rib,
The first flow path and the second flow path are communicated so that the fluid that has flowed through one of them returns from the other flow path.   The corrugated tube according to claim 1, wherein an electric wire for heating is disposed on the first rib or the second rib. The heating wire includes a first wire body and a second wire body,
The first electric wire body is disposed on one of the first rib and the second rib, and the second electric wire body is disposed on the other;
The said 1st electric wire body and the 2nd electric wire body are electrically connected in the end part vicinity of the said inner cylinder or an outer cylinder, The flexible tube of Claim 2 characterized by the above-mentioned.   The corrugated tube according to claim 1, wherein an electric wire for heating is disposed on one of the first rib and the second rib, and a thermocouple is disposed on the other.   The corrugated tube according to claim 1, wherein a thermocouple is disposed on the first rib or the second rib.   The said electric wire is arrange | positioned inside the said 1st rib or the 2nd rib, The flexible tube of Claim 2 characterized by the above-mentioned.   The serpentine tube according to claim 5, wherein the thermocouple is disposed inside the first rib or the second rib. The breathing circuit provided with the snake tube of any one of Claims 1-7.

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