1. A helical gear pump in which a drive helical gear and a driven helical gear are provided in a pump body forming a pump chamber, comprising:
a second helical gear which coaxially rotates with the drive helical gear;
a third helical gear which is engaged with the second helical gear and provided on a third shaft different from a shaft of the drive helical gear and a shaft of the driven helical gear; and
a bearing which supports the third shaft and receives a thrust force.
2. The helical gear pump according to claim 1, wherein:
design parameters of the second helical gear and the third helical gear with respect to those of the drive helical gear and the driven helical gear are that a helix angle at a base circle is twice as large and a helix direction is same.
3. The helical gear pump according to claim 1, wherein:
the second helical gear, the third helical gear and the bearing are provided in a gear chamber formed outside the pump chamber.
4. The helical gear pump according to claim 1, wherein:
the drive helical gear is driven by driving the third shaft.
5. The helical gear pump according to claim 1, wherein:
the pump body includes a first body, a second body, and a first cover and a second cover for tightly holding the first body and the second body from opposite sides;
the first body tightly held by the first cover and the second body includes the pump chamber;
a space formed between the second body and the second cover forms the gear chamber; and
the bearing is provided on the second cover.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A vascular closure device comprising:
a hollow, perforated tube;
sealing material configured to flow out of the perforated tube and into a tissue tract to close a hole in a blood vessel;
a vessel locating member insertable through the perforated tube and the hole, the vessel locating member being axially movable relative to the perforated tube and the hole, the vessel locating member being expandable within the vessel to temporarily seal the hole internally, the vessel locating member comprising a tube having a plurality of slits extending along a length thereof to define a plurality of deformable arms;
wherein the vascular closure device is configured to be inserted into the tissue tract;
wherein the vascular closure device comprises a plurality of holes so that the sealing material flows out of the vascular closure device into the tissue tract in a direction that is not parallel to the tissue tract, wherein the plurality of holes increase in size moving distally along a length of the vascular closure device to provide dispensing of greater amounts of the sealing material adjacent to the hole in the blood vessel.
2. The vascular closure device of claim 1 wherein the vascular closure device is configured so that the sealing material flows out of the vascular closure device in a direction that is at least substantially perpendicular to the tissue tract.
3. The vascular closure device of claim 1 wherein the perforated tube is configured to dispense the sealing material from the vascular closure device, the perforated tube having a distal end that is blocked to prevent the sealing material from flowing out of the perforated tube in a direction that is parallel to the tissue tract.
4. The vascular closure device of claim 3 wherein the perforated tube includes the plurality of holes which are of different sizes to control the amount of sealing material dispensed at different points along the length of the perforated tube.
5. The vascular closure device of claim 1 wherein the sealing material is configured to undergo a phase change when deployed in the tissue tract.
6. The vascular closure device of claim 1, wherein the plurality of slits are arranged in a spiral pattern.
7. The vascular closure device of claim 1, wherein the vessel locating member is removable through the sealing material after the sealing material is deposited in the tissue tract.
8. A vascular closure device comprising:
a carrier tube;
sealing material positioned in and carried with the carrier tube when the carrier tube is advanced into a tissue tract, the sealing material being configured to be deployed in the tissue tract to close a hole in a blood vessel;
a vessel locating member being insertable through and axially movable relative to the carrier tube, the vessel locating member being insertable through the hole at a non-perpendicular angle relative to a longitudinal axis of the vessel and expandable within the vessel to temporarily seal the hole internally, the vessel locating member comprising a plurality of deformable arms and an elastic membrane covering the plurality of deformable arms, the deformable arms, when expanded, being arranged parallel with the an internal wall of the vessel prior to contacting the internal wall to temporarily seal the hole internally, the vessel locating member being spaced apart from the sealing material at a predetermined distance such that when the vessel locating member is positioned against an interior wall of a blood vessel, the sealing material is positioned outside of the hole in the blood vessel;
a pull wire operable to move the vessel locating member between expanded and contracted positions;
wherein the vascular closure device is configured to deploy the sealing material in the tissue tract by retracting the carrier tube to expose the sealing material to the tissue tract; and
wherein the sealing material is configured to flow into the tissue tract when exposed to the tissue tract upon retracting of the carrier tube.
9. The vascular closure device of claim 8 comprising a stopper positioned between the carrier tube and the sealing material to prevent the sealing material from moving proximally when the carrier tube is retracted.
10. The vascular closure device of claim 8 wherein the sealing material undergoes a phase change when deployed in the tissue tract.
11. The vascular closure device of claim 8 wherein the vascular closure device is configured so that the sealing material flows out of the vascular closure device in a direction that is not parallel to the tissue tract.
12. The vascular closure device of claim 8 comprising a vessel locating member configured to be inserted through the hole in the blood vessel to locate a wall of the blood vessel that is adjacent to the hole.
13. The vascular closure device of claim 8, wherein the vessel locating member comprises a tube having a plurality of spiral slits formed along a length thereof, the plurality of deformable arms being formed by the plurality of spiral slits.
14. A vascular closure device comprising:
a vessel locating member configured to locate a wall of a blood vessel that is adjacent to a hole in the blood vessel, the vessel locating member being insertable through the hole at a non-perpendicular angle relative to a longitudinal axis of the blood vessel;
a wire extending proximally from the vessel locating member;
an indicator member connected to the wire;
a tube;
the indicator member being visible from outside the tube, the indicator member being configured to distally move relative to the tube to indicate, based on the indicator member’s location relative to the tube, when the vessel locating member is pulled against the wall within the blood vessel;
wherein the vessel locating member includes a plurality of structural support members covered by a resilient material;
wherein the vessel locating member moves between an expanded configuration wherein the structural support members are arranged parallel with an interior surface of the blood vessel prior to contacting the interior surface to allow the vessel locating member to contact the interior surface of the wall of the blood vessel to create a temporary seal with the interior surface using the resilient material to provide hemostasis, and a contracted configuration to allow the vessel locating member to pass through the hole in the blood vessel;
wherein distal ends of the structural support members are connected to each other and proximal ends of the structural support members are connected to each other in the expanded and contracted configurations.
15. The vascular closure device of claim 14 wherein the vessel locating member includes a tube having a wall with a plurality of cuts extending in a length direction along the tube to form the structural support members, the wall of the tube being configured to expand where the structural support members are located when the tube is compressed.
16. The vascular closure device of claim 14 wherein the vessel locating member is formed by nitinol tube.
17. The vascular closure device of claim 14 wherein the resilient material includes isoprene.
18. The vascular closure device of claim 14 comprising sealing material configured to be deployed adjacent to the hole and outside of the blood vessel.
19. The vascular closure device of claim 14, further comprising a pull wire connected to the vessel locating member and operable to move the vessel locating member between the expanded and contracted configurations.