BACKGROUND

The present disclosure generally relates to apparatus and methods for opening a connection site between two flexible thermoplastic conduits, such as, for example, a sterile connection site in fluid flow tubing in a medical fluid flow circuit employed in collecting, processing or treating medical fluid such as blood or blood components.

It is well known in the medical industry in general and particularly in the blood banking field to use connection systems for connecting two separate tubing segments of a fluid flow set or circuit in a manner that prevents the introduction of contaminants or preserves the sterility of the tubing, if pre-sterilized, during the connection process. Such systems have found application both in the large scale assembly or manufacture of fluid flow circuits and in the hands of the ultimate user for on-site assembly of fluid flow circuits having a desired configuration. For example, a user may desire to carry out a particular medical procedure, such as for collecting, processing or treating blood and blood components. These connection devices or systems are commonly referred to in the medical field as sterile connection or sterile docking devices.

Known connection devices or systems include electron beam systems, as in U.S. Pat. No. 5,009,645; radiant energy systems that melt facing membranes of fluid flow conduits, as in U.S. Pat. No. 4,157,723, and heated wafer systems that employ expensive wafers for cutting and heating tubing segments that are bonded or spliced together while the ends remain at a molten or semi-molten elevated temperature, such as in U.S. Pat. Nos. 4,753,697, 5,158,630, 5,156,701 and 5,279,685.

More recently, a novel rotary connection system and apparatus has been described that connects flexible thermoplastic tubing segments by heat or melt bonding the ends together while the ends are individually clamped into a closed position, preventing ambient contamination. Such a system, which does not require the use of heated wafers, is described in detail in U.S. patent application publication no. 2013/0153048, which is incorporated by reference herein in its entirety.

The connection made by heated wafer systems as well as by the wafer-free apparatus described above may have a temporary closed condition or crimped shape due to the high temperature and clamping of the tubing segment ends during connection. More specifically, as a result of the particular connection process, a portion of thermoplastic material from the tubing, also referred to as a “skin”, “membrane” or “web,” may close or reduce the size of the lumen between the tubing segments. In other words, after the connection is made, the tubular segments remain crimped or stuck together at the connection site, and the cross section of the tubular segments is reduced or flattened along a seal line between the tubing segments. This thermoplastic blocking portion of the connection can be broken or otherwise disrupted to open the lumen for fluid flow between the tubing segments by light external pressure or manipulation, including manual or mechanical manipulation, at the connection point or site. Examples of mechanical manipulation may be found in, for example, U.S. Pat. Nos. 4,610,670; 4,619,642 and 5,674,333 and EP No. 0599057 B1 and WO 2011144561 A1. U.S. Pat. No. 9,533,135 shows the use of gas pressure or vacuum to open a connection site.

The subject matter of this description relates to an apparatus and method to automatically break or otherwise disrupt the thermoplastic skin or web and therefore more fully open such a connection site and the lumen of the tubing segments to allow or improve fluid flow between the connected tubing segments.

