1. Field of the Invention
The present invention relates in general to flexible plastic tubing and, more particularly, to apparatus and methods for making such tubing, which tubing is flexible and includes an external helical support rib or bead. More particularly, this invention relates to such a tubing product having a main elongate passage or lumen in which fluid may flow, and which may also include one or more additional lumens defined or carried within the support bead, as well as one or more electrical conductors which may be used, for example, to effect electrical resistance heating of the fluid conveyed in the main lumen, or which may be used to convey electrical signals along the length of the tubing. The tubing product may also include one or more optical fibers, which also may be used, for example, to convey optical signals along the length of the tubing or to convey light which may be used for illumination or to power a photovoltaic device.
2. Related Technology
Tubing which is flexible, and has a relatively thin wall and an integral helical supporting bead is known in the art. Such a flexible support-bead tubing construction provides substantial crash resistance while leaving the tube wall flexible enough to permit short-radius bends without collapsing or kinking the tube. The versatility of this kind of tubing is evidenced by its wide applicability in construction, ventilation, manufacturing processes, auto washes, medical devices, hospitals and other fields.
The walls of a support-bead tubing can be quite thin to minimize overall weight. This light weight for the tubing is an important feature when, for example, the tubing is used with an inhalation machine to provide a patient with more comfort during oxygen or medicated air delivery. Two other features of known thin wall support-bead or bead-reinforced tubing are transparency and smoothness of bore. Transparent plastic material permits inspection of the fluid coursing through the tube, to detect, for example, the presence of moisture in an anesthetic or patient oxygen delivery application. A smooth inner surface of such a tube is desirable to keep the tube free from deposits of contaminants and to discourage non-laminar flow. Also, this smooth inner surface makes the tubing product more desirable for applications in which the tubing is to be re-used. The smooth inner surface promotes easy and effective cleaning, sanitizing, and sterilizing of the tubing product.
U.S. Pat. No. 3,910,808 to Steward, discloses apparatus for forming a thin-walled, flexible, crush resistant tubing having a support-bead. Steward discloses a method for extruding a plastic strip having a longitudinal rib, and the method and apparatus for helically winding the strip about an axis to produce a corrugated flexible tubing having a smooth bore and a helical external support bead.
Many applications, however, require or are enhanced by the presence of controlled heating of such tubing. Neonatal patients, for example, as well as patients in shock or who are sustained on breathing equipment, are among those who benefit from gas flowing through heat-conditioned tubing.
U.S. Pat. No. 5,454,061 to Lenart Carlson, provides a helically wound and helically ribbed plastic tubing incorporating an electrically conductive heating wire and an apparatus and method for making the tubing. In this patent a plastic ribbon is wound about an axis into a tube with one edge of each lap overlapping and heat bonded to an edge of the preceding lap as the tubing is rotationally formed. A conductive wire is embedded in the ribbon and a bead is applied and heat-bonded onto the tubing, encapsulating the conductive wire during rotation of the tubing, and providing a unitary structure including a conductive wire integral to a flexible tubing. Again, the tubing has a corrugated crevice-free outside surface and a smooth inside surface. Coolant is applied to the tubing for cooling the unitary ribbon, wire, and bead during formation of the tubing, and also to assist in advancing the tubing along the axis of the manufacturing apparatus.
One prior application of a hollow ribbed pipe can be found in U.S. Pat. No. 5,051,081 assigned to Toyox. In this patent hollow ribs are produced by extrusion, and are then wrapped around the outer periphery of an extruded pipe. This construction of a tubing product has several deficiencies. For example, the interior walls of the hollow rib produced by this apparatus contain connection lines through which a gaseous material could escape into the ambient, and the rib is extruded in such fashion that it would not be possible to separate it from the tube and attach it to a hose barb. That is, the shape of the lumen or passage in this rib is not generally round.
Prospective new applications for such flexible tubing makes desirable the ability to transmit electrical or optical signals along the tubing. An example of this in which it would be desired to transmit optical signals along a tubing product would be an inhalation therapy apparatus including a face mask connected by a length of tubing to a machine providing therapeutic air or vapor for inhalation therapy. This face mask would desirably include instrumentation to monitor the patient's condition, or to control the inhalation therapy machine. An example of a monitoring device is the use of an optical pulse oxygenation meter at a distal end of the tubing product, perhaps carried in the inhalation mask, and light for which is transmitted along the tubing from a light source at or adjacent to the proximal end of the tubing. A return signal from the pulse oxygenation meter is also to be transmitted back to the proximal end of the tubing.
No prior tubing product, method of manufacture, or apparatus is known which provides a thin-walled, flexible, smooth bore tube having a contemporaneously wound supporting and encapsulating bead, which provides for communication of optical signals or light along the tubing product, and with the bead, and tube forming a unitary structure with a smooth, crevice-free outer surface.
In view of the deficiencies of the related art as discussed above, it is a primary object of the present invention to provide a flexible, lightweight, crush-resistant tubing having one or plural supporting beads helically wound about and integral with the surface of the tubing. The tubing is constructed with smooth walls free from joints or connection lines. The bead carries one or plural optical fibers capable of transporting or communicating light or optical signals along the tubing.
It is another object of this invention to provide apparatus and method for inexpensively making such a tubing product, having a supporting bead and at least one interior lumen, and with the tubing including one or plural optical conductors extending along the tubing.
Additional applications of the present invention, as well as the method of manufacturing and advantages resulting from the use of the present inventive tubing product will be apparent to those skilled in the art from a consideration of several fully detailed exemplary embodiments described and depicted herein. To aid in the explanation of the exemplary embodiments, reference will be made to the Figures of the appended sheets of drawings, which Figures will first be described briefly. That is, the advantages and features of the present invention will be better understood in view of the following description of several exemplary preferred embodiments of the invention when considered in conjunction with the accompanying drawings in which:
Viewing now
Defined within the support bead 26 is a fine-dimension lumen or passage 28. Although only a single lumen 28 is illustrated, the invention is not so limited and the support bead 26 may define plural such lumens. This lumen passage 28 extends from one end of the support bead to the other, so that it also opens on opposite ends of the tubing 10. As is indicated by the arrows 30 on
Also carried in the tubing product 10 upon the wall section 20 and adjacent to the lap joint 24, is a pair of fine dimension fiber optic conductors 32 and 34. These fiber optic conductors 32 and 34 each include a jacket portion, indicated by the arrowed numeral 36, and a central optical fiber portion, indicated by the arrowed numeral 38. The optical fibers 32 and 34 are embedded in the tubing 10 beneath the rib 26. During manufacturing of the tubing product 10, the fiber optic conductors 32 and 34 are laid upon the wall section 20 adjacent to the lap joint 24, and the support bead 26 is placed upon the underlying structure while the plastic of the wall section 24 and support bead 26 are both still molten. Consequently, the fiber optic conductors 32 and 34 are embedded into both the wall structure 20 and into the support bead 26.
As is seen in
In
In
A concrete example of an embodiment of the system seen in
Moreover, in this case, the output signal of the sensor 50 is conducted back to the respiratory therapy machine (i.e., to the source/receiver 42a) via the other of the optical conductors 32a or 34a. Those ordinarily skilled in the pertinent arts will recognize that the invention is not limited to having one optical conductor supply light while the other carries a return optical signal. In fact, by using multiplexing techniques, several return signals may be carried on the same optical fiber which is also carrying a light source beam.
Further, the lumen 28a in such a respiratory therapy machine might be used to convey a supply of liquid therapeutic agent to the face mask 46a for atomization at this face mask into the inhaled tidal air flow to patient 48a. In contrast, heretofore it has been common for liquid therapeutic agents to be administered (i.e., atomized) into the tidal air flow of a respiratory therapy machine at the machine itself. The atomized agent is then conveyed along a tubing to the patient's face mask. This common conventional practice presents the hazard that liquid (i.e., resulting from vapor dropping out of the tidal air flow) may slug in the tubing connecting the machine to the patient's face mask, recalling that the air flow in the tubing is tidal and some vapor may have a long residence time in the tubing. It is very undesirable to have a patient aspirate a slug of liquid therapeutic agent. The present invention avoids this common and long standing risk because the therapeutic agent may be atomized right at the face mask and cannot drop out of vapor state before being inhaled by the patient 48a. In such an embodiment, there is no significant risk of the vapor slugging in the tubing because very little or no vapor will enter the tubing.
In
In this invention, the pulse oxygenation signal could be obtained by a sensor (i.e., part of sensor package 50) clipping onto the patients earlobe, and there obtaining both pulse rate and blood oxygenation signals. These signals can be obtained optically, and sent back to the machine 42b along the optical conductors 32b and 34b. Thus, the added cable of a conventional pulse oxygenation meter is eliminated from the patient room environment by use of this invention.
Other uses for the sensor package 50, may include such things as monitoring patient movements (i.e., respiration rate for example). A variety of optical and fluidic sensors are available which may be employed within the sensor package 50. Further, as will be seen, the present invention is not limited to sensors powered only by fluidics or by light. In fact, electrical sensors may be utilized at the distal end of tubing product 10, as will be further explained.
Considering now an alternative embodiment of the tubing product 10, in this case indicated in
In this case, the single optical conductor 52 may provide for light transmission along the tubing product, with utilization of the light transmitted (or of optical source light and return signal light) being substantially as already described by reference to an earlier embodiment, and may be also carried on the single optical conductor 52.
Considering now
Finally, turning now to
Those skilled in the art will further appreciate that the present invention may be embodied in other specific forms without departing from the spirit or central attributes of the invention. Because the foregoing description of the present invention discloses only particularly preferred exemplary embodiments of the invention, it is to be understood that other variations are recognized as being within the scope of the present invention. Accordingly, the present invention is not limited to the particular embodiments which have been described in detail herein. Rather, reference should be made to the appended claims which define the scope and content of the present invention.
Number | Name | Date | Kind |
---|---|---|---|
4354051 | Kutnyak | Oct 1982 | A |
4490575 | Kutnyak | Dec 1984 | A |
5046531 | Kanao | Sep 1991 | A |
5416270 | Kanao | May 1995 | A |
5454061 | Carlson | Sep 1995 | A |
5975144 | Akedo et al. | Nov 1999 | A |
6016845 | Quigley et al. | Jan 2000 | A |
6286558 | Quigley et al. | Sep 2001 | B1 |
6367510 | Carlson | Apr 2002 | B1 |
Number | Date | Country | |
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20030183294 A1 | Oct 2003 | US |