The present invention relates to a fluid pump used in a lavage instrument.
In many medical and surgical procedures, irrigating wounds, and surgical areas with fluids and/or removing various irrigating fluids from the surgical area are often necessary. Lavage instruments are well known in the medical arts. Lavage instruments that are connected to an external vacuum source to additionally provide an aspiration function have been developed. Typically, lavage instruments have been connected to external fluid pumps, which supply irrigation fluids to the lavage instrument from an external fluid source, such as a hanging fluid bag. Heretofore, lavage instruments that include internal fluid pumps have been electrically powered, which increases the size, weight and cost of the lavage instrument.
Utility Pat. No. 5,542,918 issued to Atkinson discloses a vacuum driven fluid pump for an aspiration/irrigation instrument. However, the present invention makes significant improvements in apparatus components and functional capabilities. First, the present invention is easy to make and is easy to use. Second, functionally, the present invention can provide continuous fluid flow or at least higher frequency pulsatile fluid flow and is capable of simultaneously aspirating fluid and irrigating fluid.
For these reasons a lavage instrument, which includes an internal fluid pump that is lightweight, inexpensive, disposable and driven by an alternative power source is needed.
The fluid pump of this invention is used in a lavage instrument that is driven by vacuum pressure supplied by an external vacuum source. The vacuum driven fluid pump is well suited for lavage instruments that are already connected to an external vacuum source to provide aspiration functions.
These and other features, aspects and advantages of the present invention will become better understood with reference to the following description, claims, and accompanying drawings. Therefore, the form of the invention, as set out above, should be considered illustrative and not as limiting the scope of the following claims.
The preferred embodiment of the present invention represents a vacuum driven pump for a lavage instrument as shown in
With reference to
There are two one-way valves 11, 12, 13, and 14 at each end of the cylinder 1. The first and second chambers 2 and 3 each have two valves: the first and second inlet valves 11 and 13 allow fluid to enter the first and second chambers 2 and 3 respectively; the first and second outlet valves 12 and 14 allow fluid to exit the first and second chambers 2 and 3 respectively.
With further reference to
When the vacuum switch connects vacuum to the second port 10 in the second chamber 3, the first and second pistons 5 and 6 move in opposite directions. Now, the first chamber 2 expels fluid via the first outlet valve 12, while the second chamber 3 draws fluid via the second inlet valve 13.
If the first and second outlet valves 12 and 14 are connected to the same delivery tube 15, and the first and second inlet valves 11 and 13 are connected to the same liquid source 16, the fluid is able to flow continuously in and out of the cylinder 1.
Further, with reference to
In the event that both the top and bottom trumpet valves 17 and 18 are utilized, both the top and bottom trumpet valves 17 and 18 are normally in the closed position, disconnected from the vacuum source. The bottom trumpet valve 18 connects the vacuum source to the aspiration pipet 29 when the bottom trumpet valve is pushed down until hole and channel 22 matches hole 26. This configuration is for suction purposes only. The top trumpet valve 17 communicates the vacuum source to both the aspiration pipet 29 and the tube 35 (depicted in
In another configuration, in the event that a single trumpet value is utilized, for example the combination of the top trumpet valve 17 or the bottom trumpet valve 18 into a single trumpet valve, the one trumpet valve to function as above can be operated at two levels. The first level, the first position, is suction only (connected to the suction pipet). The second level, the second position, is suction and sprinkling (connected to both the pipet and the pump).
The delivery tube 15 and the aspiration pipet 29 may be located side-by-side or may be nested, with the delivery tube 15 located inside the aspiration pipet 29, as shown in
With reference to
The following is the order of the change between vacuum and atmosphere in the first chambers 2: vacuum to atmosphere to vacuum to atmosphere. The following is the corresponding order of the change between vacuum and atmosphere in the second chamber 3: atmosphere to vacuum to atmosphere to vacuum. Within a chamber, the following occurs: vacuum to atmosphere to vacuum to atmosphere. These switches from the first and second chambers 2 and 3 and between vacuum and atmosphere are carried out automatically.
The auto-switch 40 is located between the first chamber 2 and the second chamber 3 at the interface of the separating wall 4 and the body cylinder wall. The auto-switch 40 comprises cylindrical tubing 30 that crosses the separating wall 4 with two opening ends, the first and second ports 9 and 10. A cylindrical body casing 31 longer than the cylindrical tubing 30, with both ends closed, but has two side holes, the first and second side holes 32 and 33, at each end. The first and second side holes 32 and 33 open to common opening 34 that is connected to the tube 35 leading to the vacuum source. The cylindrical body casing 31 also has first and second channels 36 and 37 at each end on the other side of the cylindrical body casing 31 to match the side openings 38 and 39 on the wall of the cylinder casing 1, near the separating wall 4, to communicate with the atmosphere.
Alternatively, the auto-switch 40 can be located in the center of the separating wall 4. In addition, the auto-switch could also be attached to, a part of, or incorporated with the rod 7.
The cylindrical body casing 31 slides into the cylindrical tubing 30. While the fit of the cylindrical body casing 31 inside the cylindrical tubing 30 is air tight, the cylindrical body casing 31 is still capable of shuttling from left to right. When the cylindrical body casing 31 slides completely into the cylindrical tubing 30 and both ends of the cylindrical body casing 31 and the cylindrical tubing 30 are lined up on one side such as the first chamber 2, on the other side, the second chamber 3, the other end of the cylindrical body casing 31 protrudes longer than the cylindrical tubing 30 so the cylindrical body casing 31 is exposed in the second chamber 3. During this configuration, in the first chamber 2, the first side hole 32 to the vacuum is closed, but the first channel 36 to the atmosphere is open. Also during this configuration, in the second chamber 3, the second side hole 33 to the vacuum is open to the second chamber 3, while the second channel 37 to the atmosphere is disconnected. As a result, when the vacuum controlled 17 connects the vacuum source to the auto-switch, the vacuum force will drive the second piston 6 to move toward the separating wall 4 with an accelerated rate. When the second piston 6 comes to the end and against the extended part of the cylindrical body casing 31, it will push the cylindrical body casing 31 so that now, the second chamber 3 is even and the first chamber 2 has the extended part of the cylindrical body casing 31. In the event the vacuum is applied to the first chamber 2, the opposite will result.
Alternate embodiments of the present invention are illustrated in
Thus, the present invention provides a lavage fluid pump that is lightweight, inexpensive, disposable, easy to make, easy to use, and without need of electric power of batteries. The present invention is low-noise, environmentally friendly, and cost-effective.
As such the method of making and using the device detailed above constitute the inventor's preferred embodiment and alternate embodiments to the invention. The inventor is aware that numerous configurations of the device as a whole or some of its constituent parts are available which would provide the desired results. While the invention has been described and illustrated with reference to specific embodiments, it is understood that these other embodiments may be resorted to without departing from the invention. Therefore the form of the invention set out above should be considered illustrative.
This application is based on and claims priority from provisional patent application Ser. No. 60/512,332 filed on Oct. 17, 2003.
Number | Date | Country | |
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60512332 | Oct 2003 | US |