Apparatus for conveying liquids
First Claim
Patent Images
1. A device comprising:
- a liquid source containing liquid;
intermittently energizable pump means for drawing liquid to be conveyed from said liquid source to an input of said pump means, said pump means having a pump action causing a substantially fixed amount of said liquid to be drawn in a conveying direction from said liquid source; and
filter means, connected between said liquid source and said input of said pump means, dimensioned for preventing air bubbles having a larger diameter than a predetermined minimum diameter from freely passing through said filter means and for requiring a pressure needed for conveying through said filter means an air bubble, said air bubble having a larger diameter than said prescribed minimum diameter, said pressure being greater than a maximum pressure drop produced in a pump action by said liquid flowing through said filter means, and said filter means having an admission opening formed by a gap having a length in a direction substantially transverse to said conveying direction giving said gap a volume which is greater than said substantially fixed amount.
1 Assignment
0 Petitions
Accused Products
Abstract
In a device for conveying liquids having an intermittently energized pump and a filter for retaining air bubbles preceding the input side of the pump, the filter contains an admission opening in the form of a long gap and the gap volume is greater than the conveying volume of the pump given a single pump action. Even an air bubble that nearly completely covers the gap cannot be conveyed therethrough as long as the gap is in contact with the liquid to be pumped at some location.
-
Citations
25 Claims
-
1. A device comprising:
-
a liquid source containing liquid; intermittently energizable pump means for drawing liquid to be conveyed from said liquid source to an input of said pump means, said pump means having a pump action causing a substantially fixed amount of said liquid to be drawn in a conveying direction from said liquid source; and filter means, connected between said liquid source and said input of said pump means, dimensioned for preventing air bubbles having a larger diameter than a predetermined minimum diameter from freely passing through said filter means and for requiring a pressure needed for conveying through said filter means an air bubble, said air bubble having a larger diameter than said prescribed minimum diameter, said pressure being greater than a maximum pressure drop produced in a pump action by said liquid flowing through said filter means, and said filter means having an admission opening formed by a gap having a length in a direction substantially transverse to said conveying direction giving said gap a volume which is greater than said substantially fixed amount. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15)
-
-
16. A device comprising:
-
a liquid source containing liquid; intermittently energizable pump means for drawing liquid from said liquid source, said pump means having an input and a pumping action which draws a substantially fixed amount of said liquid from said source to said input in a conveying direction; and filter means, disposed between said liquid source and said input of said pump, dimensioned for preventing air bubbles from freely passing through said filter means having a larger diameter than a predetermined minimum diameter and for requiring a pressure needed for conveying through said filter means an air bubble, said air bubble having a larger diameter than said predetermined minimum, said pressure being greater than a maximum pressure drop produced in a pump action by said liquid flow through said filter means, said filter means having a housing with an annular opening through which said liquid is conveyed, and a disk disposed in said opening forming a gap between said housing and said disk, said gap having a length in a direction substantially transverse to said conveying direction giving said gap a volume which is greater than said substantially fixed amount. - View Dependent Claims (17, 18, 19, 20, 21, 22)
-
-
23. An implantable infusion apparatus comprising:
-
a reservoir containing liquid medication; intermittently energizable pumping means for drawing a substantially fixed dose of said medication in a conveying direction from said reservoir to said input of said pumping means; filter means, disposed between said reservoir and said input of said pumping means, dimensioned for preventing air bubbles having a diameter larger than a predetermined minimum diameter from freely passing through said filter means and for requiring a pressure needed for conveying through said filter means an air bubble, said air bubble having a diameter larger than said predetermined minimum diameter, said pressure being greater than a maximum pressure drop produced in a pump action by said medication through said filter means, said filter means having a housing with an annular opening therein through which said medication is conveyed, and a disk disposed in said opening forming an annular gap in combination with said housing, said gap having a length in a direction substantially transverse to said conveying direction providing said gap with a volume which is greater than said substantially fixed dose. - View Dependent Claims (24, 25)
-
Specification