The present disclosure relates generally to the field of sealing apparatuses for fluid systems. More specifically, the disclosure relates to a sealing apparatus for separating and sealing plastic tubing for handling biological fluids.
In some applications, fluid flowing through conduits or tubing in a system may be divided into separate streams for purposes of collection or further processing. For example, an apheresis machine may use a centrifuge or other blood separation device to separate blood collected from a subject into its constituent components, such as red blood cells, platelets, plasma, or the like. After separation, the apheresis machine may provide the blood components to collection bags or other containers via polymer tubing. Once a collection bag has been filled, it may be separated from the apheresis machine by cutting through the tubing and sealing the ends of the tubing. However, if tension is applied to the tubing during the sealing process (e.g., through inadvertent contact with the tubing on either side of the sealing apparatus), the sealing operation may fail, resulting in an incomplete seal and a leak in the tubing.
One embodiment relates to a tube sealing apparatus that includes a body defining an opening configured to receive a length of tubing. The apparatus also includes a movable sealing head located within the opening and configured to apply a radio frequency signal to the tubing to seal the tube. The apparatus further includes one or more movable tube supports that move with the sealing head to contact the tubing such that compressive support is applied to the tubing while the sealing head seals the tube.
Another embodiment relates to a tube sealing apparatus that includes an electronic circuit that generates a radio frequency signal. The apparatus also includes a housing that houses the electronic circuit and a cable connected to the circuit and configured to transmit the radio frequency signal from the circuit. The apparatus further includes a hand unit connected to the cable that receives the radio frequency signal. The hand unit defines an opening configured to receive a length of tubing. The hand unit also includes a movable sealing head located within the opening and configured to seal the tube using the radio frequency signal. The hand unit further includes one or more movable tube supports that move with the sealing head to contact the tubing such that compressive support is applied to the tubing while the sealing head seals the tube.
A further embodiment relates to a tube sealing apparatus that includes sealing means for applying a radio frequency signal to a length of tubing to seal the tubing. The apparatus also includes actuator means for moving the sealing means from a first position to a second position in which the sealing means applies compressive force to the tubing. The apparatus further includes support means for applying compressive support to the tubing while the sealing means seals the tubing.
These embodiments are mentioned not to limit or define the scope of the disclosure, but to provide example implementations of the disclosure to aid in understanding thereof. Particular embodiments may be developed to realize one or more of the following advantages.
Features, aspects, and advantages of the present invention will become apparent from the following description, appended claims, and the accompanying exemplary embodiments shown in the drawings, which are briefly described below.
Like reference numbers and designations in the various drawings indicate like elements.
It is to be understood that the following detailed description is exemplary and explanatory only, and is not restrictive of the invention as claimed. One or more embodiments may allow fluids to be approximately equally distributed between x number of finished good containers. One or more embodiments may allow component self regulation of distributing a larger amount of pre-distributed fluid approximately equally into x number of finished good containers without requiring the manual intervention of an operator for burping or redistribution after an automated process has completed. One or more embodiments may save time and increase efficiency in an overall fluid distribution process. One or more embodiments may provide a more consistent distribution of finished processed fluid and allow a wider variety of orientations of bag positioning. One or more embodiments may be altered to allow better ergonomics, packaging or performance.
A fluid system, such as that found in a blood apheresis machine, may be utilized to process whole blood or other suspensions of biological material in a fluid. The system may include conduits or tubing configured to convey fluid through the system to and/or from one or more collection bags or other containers. For example, a blood apheresis machine may provide separated blood components to different collection bags via tubing. In some embodiments, the tubing in the fluid system is formed of non-reactive materials that are suitable for handling biological fluids and may be configured for a single use (e.g., intended to be disposed after each use). The tubing may be formed of a relatively flexible material, such as PVC or silicone, in some embodiments. While described with reference to a blood donor tube used in an apheresis machine, the concepts described herein may be applied to other tubes, with or without solutions, such as transfer packs. Other forms of fluid systems may include, but are not limited to, dialysis machines, medical devices configured to administer a medicament, and other medical devices configured to take a sample of a biological fluid from a subject.
Referring generally to
According to an exemplary embodiment, the sealing device 10 divides and seals the tubing 20 with a heat seal. The tubing 20 is received between a pair of sealing heads 14 mounted to frames 12 (e.g., as shown in
In various embodiments, each sealing head 14 may include a pointed or sharp heat sealing surface 17 configured to seal tube 20 in such a manner that allows the separated portion of tube 20 to be snapped apart, without the need or use of a separate cutting device. Surfaces 17 may be configured to seal a septum into the tubing to allow this feature of snapping apart.
While the sealing device 10 is described herein as a heat sealing mechanism, in other embodiments, the tubing 20 may be divided and sealed in other suitable manners. For example, the sealing head 14 may be configured to physically crimp the tubing 20 (e.g., by folding the tubing back on itself one or more times and crimping the folded tubing).
During the sealing process, the strength of the tubing 20 may be reduced, leaving it more susceptible to damage. While the compressed portion is being heated, a tension applied to tubing 20 on either side of the sealing device 10 may cause an incomplete weld to form, resulting in a failed seal and a leak in the tubing 20. Such a tension, for example, may result from incidental contact to the tubing 20. For example, a tension of as little as 250 grams-force applied to a typical form of tubing used in a blood or blood component collection system may be sufficient to cause an incomplete weld.
According to an exemplary embodiment, tube supports 16 are provided on either side of one or both of the sealing heads 14. The tube supports 16 are protrusions that apply a compressive force to the tubing 20 to isolate the sealed portion 18 from the portions of the tubing 20 extending outside of the sealing device 10 during the sealing process. Any number of tube supports 16 may be used in sealing device 10 and may be located in any number of positions relative to sealing heads 14. According to an exemplary embodiment, the sealing device 10 includes four tube supports 16, with one tube support 16 on either side of each of the sealing heads 14. In other embodiments, tube supports 16 may be provided on either side of one of the sealing heads 14 and may be configured to compress the tubing 20 against another body, such as the opposing frame 12. In still other embodiments, tube supports 16 may only be provided on one side of the sealing heads 14.
As shown in
In some embodiments, the tube supports 16 are formed of a rigid, non-electrically conductive material to resist heat transmission to the tubing 20 on either side of the sealed portion 18. In one exemplary embodiment, the tube supports are formed of a ceramic material. In other embodiments, the tube supports 16 may be a polymer material (e.g., a thermoset plastic, thermoplastic, etc.) such as polyoxymethylene, sold under the trade name Delrin® by DuPont. In some embodiments, tube supports 16 may comprise one or more materials that are electrically non-conductive (e.g., an electrical insulator) and thermally conductive. Tube supports 16 may be cooled by way of a non-electrically conductive, but thermally conductive material attached to a cooling heat sink, such as heat sink 902 shown in
The tube supports 16 may be rigidly mounted, or may be spring mounted to apply a fixed pressure to the tubing 20 and support the tubing 20 from externally applied incidental force during sealing. As shown in
The tube supports 16 may be configured to actuate simultaneously with the sealing heads 14. As shown in
According to one alternative embodiment, the sealing device designs shown in
Referring now to
Referring now to
The sealing apparatus 30 further includes an electronic circuit 38 coupled to the sealing heads 14. The electronic circuit 38 senses when the sealing heads 14 close, either manually or automatically (e.g., with an electrical, hydraulic, or pneumatic actuator) and provides a radio frequency (RF) signal to the sealing heads 14. The tube supports 16 engage the tubing 20. With the sealing heads 14 and the tube supports 16 closed on the tubing, the electronic circuit 38 measures the change in dielectric constant of the tubing material between the sealing heads 14. The electronic circuit 38 automatically turns off the RF signal if the measured dielectric constant indicates a threshold thickness of the tubing (i.e., the sealed portion 18) or after a predetermined time period (e.g., 1 second). If the sealing heads 14 are automatically actuated, the electrical signal may then withdraw the sealing heads 14. The sealing apparatus 30 may include a visual indicator such as an LED or an audio indicator to inform the user that the sealing process is complete.
Referring now to
According to an exemplary embodiment, tube supports 116 (e.g., fixtures, cleaners, etc.) are provided on either side of the sealing head 114. The tube supports 116 are moveable members that apply a compressive force to the tubing 120 to isolate the sealed portion 118 (see
At the beginning of the sealing process, the tube 120 is placed in the sealing device 110 between the tube supports 116 and the plate 112, as shown in
The tube sealing system as shown in
Referring now to
The sealing apparatus 130 may be a desktop or tabletop unit that receives power from an outlet (e.g., a 110 VAC power source) through a cable or cord 134 or may receive power from batteries. An electronic circuit 138 coupled to the sealing heads 114 may be contained within the lever 140. In other embodiments, the cord 134 may couple the sealing apparatus 130 to another unit housing the electronic circuit 138.
Tubing 120 is inserted between the tube supports 116 and the plate 112. The sealing device 110 is actuated manually by pushing down on the lever 140. A user compresses the tubing 120 in the sealing device 110 as described above. The tube supports 116 engage the tubing 120 and push fluid in the tubing 120 away from the sealing area. The electronic circuit 138 senses when the sealing head 114 closes and provides a radio frequency (RF) signal to the sealing head 114, thereby causing sealing head 114 to heat up and seal the tubing. With the sealing head 114 and the tube supports 116 closed on the tubing, the electronic circuit 138 measures the change in dielectric constant of the tubing material between the sealing head 114 and the plate 112. The electronic circuit 138 automatically turns off the RF signal if the measured dielectric constant indicates a threshold thickness of the tubing (i.e., the sealed portion 118) or after a predetermined time period (e.g., 1 second). The sealing apparatus 130 may include a visual indicator such as an LED or an audio indicator to inform the user that the sealing process is complete.
Referring now to
The shapes of the sealing head and the clamping/gripping design features are not limited to the diagrams as shown.
The construction and arrangement of the elements of the sealing apparatus as shown in the exemplary embodiments are illustrative only. Although only a few embodiments of the present disclosure have been described in detail, those skilled in the art who review this disclosure will readily appreciate that many modifications are possible (e.g., variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters, mounting arrangements, use of materials, colors, orientations, etc.) without materially departing from the novel teachings and advantages of the subject matter recited. For example, elements shown as integrally formed may be constructed of multiple parts or elements. Some like components have been described in the present disclosure using the same reference numerals in different figures. This should not be construed as an implication that these components are identical in all embodiments; various modifications may be made in various different embodiments. It should be noted that the elements and/or assemblies of the enclosure may be constructed from any of a wide variety of materials that provide sufficient strength or durability, in any of a wide variety of colors, textures, and combinations.
The present application claims priority to U.S. Provisional No. 61/652,707 entitled “DONOR TUBE SEALING HEAD WITH NON-TENSION TUBE SUPPORTS,” and filed May 29, 2012, the entirety of which is hereby incorporated by reference.
Number | Date | Country | |
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61652707 | May 2012 | US |