Peristaltic pump cartridge with tube standoff
Peristaltic pump cartridge 10 includes a housing 12 and a length of tubing 14 connected to the housing for engagement with a pump roller head 42. A cover plate 16 is connected to the housing 12 and oriented essentially parallel to the length of tubing 14. At least one standoff tab 18 is connected to the cover plate 16 to ensure that the length of tubing 14 is at least a known distance from the cover plate 16 to facilitate engagement of the tubing 14 with the pump roller head 42.
1. Field of the Invention
The present invention relates to peristaltic pump cartridges and more specifically, to pump cartridges having a loop of tubing material for engagement with a peristaltic pump head.
2. Description of Related Art
Peristaltic pump cartridges are well known in the art. Peristaltic pumps and the related pump cartridges for collecting aspirant from surgical sites are well known in many areas of surgery, including ophthalmic surgery.
Typically, a peristaltic pump cartridge includes some sort of housing with one or more lengths of tube for engagement with a peristaltic pump roller head. Upon operation of the peristaltic pump head, aspirant fluid is then pumped from the surgical site through tubing of the cartridge and into a collection bag or reservoir.
It is very important for the tubing and the pump cartridge to properly engage with the peristaltic pump roller head, so that the tubing is completely pinched-off at intervals by the rollers of the pump head. If proper engagement of the cartridge tubing with the pump head does not occur, then little or no aspirant will be pumped from the surgical site into the collection bag.
There have been many prior attempts to ensure that the tubing is properly engaged with the pump head. Getting the tubing between the pump head and a backing plate and to be properly engaged has typically been achieved in one of three ways. The first method is to manually thread the tubing between the head and the backing plate. This is somewhat cumbersome, time consuming, and inconvenient for a user. The second and third methods include the use of a cartridge that has a length of tubing exposed. The second method includes a threading member or finger that extends beyond the pump head, and as the pump head rotates, the finger threads the tubing onto the pump head. This requires a specially designed threading finger, but generally results in an easy to load pump. The third method includes a cartridge with a portion of the cartridge forming the backing plate. The cartridge is then urged toward the pump head. This method is also convenient for the user, but has a potential drawback in that the backing plate of the cartridge typically does not cooperate with the pump head over a sufficiently large radius. This relatively small radius of interaction can lead to unwanted pulsation and aspirant flow through the system.
Yet another prior art peristaltic pump does not use any backing plate at all. Instead, a cartridge with a loop of tubing is placed around a pump head and a cartridge holder is then moved away from the pump head until the tubing loop is sufficiently stretched, such that the rollers of the pump head pinch close the tubing without a backing plate. The extent to which the tubing must be stretched is a cause for concern. Also, without a backing plate, unwanted pulsation is likely to occur. This pulsation can result in dangerous and undesirable intraocular pressure in the eye and may also affect chamber stability during surgery.
Yet another inventive peristaltic pump system has been disclosed and is commonly assigned to Bausch & Lomb Incorporated. This inventive pump head was described in U.S. patent application Ser. No. 10/673,969 filed on 29 Sep. 2003, and is entitled “A Peristaltic Pump Cartridge Including An Aspirant Collection Bag For Use In Ophthalmic Surgery”. This application is hereby incorporated in its entirety by reference and describes in detail the operation of the peristaltic pump and the related cartridge. This peristaltic pump includes a moveable pump head which drops down, such that the loop of tubing for use with the pump head surrounds the pump head and then the pump head is then moved upwardly to engage the loop of material against the backing plate. This system requires that the loop of tubing material be in a relatively precise known location in order for the tubing material to properly engage with the pump head.
Therefore it would be desirable to have a feature of the cartridge which ensures the alignment of the tubing loop of the cartridge with the roller pump head.
BRIEF DESCRIPTION OF DRAWINGS
While the operation of the peristaltic pump and cartridge is more particularly described in the above-referenced co-pending patent application, the pump cartridge preferably includes a pressure transducer 20, irrigation fluid tubing 22, and fluid vent tubing 24, as well as handle 26.
Referring to
Thus has been described a simple, elegant, and inexpensive manner to ensure the proper alignment of peristaltic pump cartridge tubing with a peristaltic pump roller head. Other embodiments and variations of the embodiment described above may occur to those skilled in the art and still be within the scope of the present invention.
Claims
1. An ophthalmic pump cartridge comprising:
- a housing including a collection chamber for holding aspirant from a surgical site;
- a length of tubing connected to the housing for engagement with a pump roller head;
- a cover plate connected to the housing and oriented essentially parallel to the length of tubing; and
- at least one standoff tab connected to the cover plate for ensuring that the length of tubing is at least a known distance from the cover plate to facilitate engagement of the tubing with the pump roller head.
2. The cartridge of claim 1, wherein the housing is formed of thermoplastic resin.
3. The cartridge of claim 1, wherein the length of tubing includes a first end connected to an inlet and a second end connected to the collection chamber.
4. The cartridge of claim 1, wherein the cover plate includes a handle.
5. The cartridge of claim 1, wherein the cartridge includes a pair of standoff tabs and wherein the tabs include a concave end for mating with the tubing.
Type: Application
Filed: Dec 16, 2004
Publication Date: Sep 28, 2006
Inventor: Matthew Fitzgerald (St. Louis, MO)
Application Number: 11/014,474
International Classification: F04B 43/12 (20060101);