Peristaltic pump and pumphead therefor
A peristaltic pumphead comprising a pumphead housing accommodating a pumping tube, an end of the tube being provided with an end fitting having a through passage and an abutment shoulder and a threaded shank extending from the abutment shoulder into the tube the tube end abutting the abutment shoulder and being accommodated in an opening, in the pumphead housing, the abutment shoulder abutting the housing at the opening, and the end fitting being engaged by a retaining element to retain the abutment shoulder against the housing.
1. A peristaltic pumphead, comprising:
a pumphead housing accommodating a pumping tube, an end of the pumping tube being provided with an end fitting having a through passage and an abutment shoulder; and
a threaded shank extending from the abutment shoulder into the pumping tube, the tube end abutting the abutment shoulder and being accommodated in an opening in the pumphead housing, the abutment shoulder abutting the pumphead housing at the opening, and the end fitting being engaged by a retaining element to retain the abutment shoulder against the pumphead housing; wherein the threaded shank is configured to be rotated so as to draw the tube along the threaded shank towards the abutment shoulder and the opening in the pumphead housing.
2. The pumphead as claimed in claim 1 , wherein the threaded shank is tapered in the direction away from the abutment shoulder.
3. The pumphead as claimed in claim 1 , wherein the retaining element comprises a threaded portion which engages with a threaded portion of the pumphead housing.
4. The pumphead as claimed in claim 1 , wherein the end fitting comprises separable first and second parts, the first part comprising the abutment shoulder and threaded shank and the second part comprising a spigot for attachment to a tube, the retaining element being arranged to secure the first and second parts together.
5. The pumphead as claimed in claim 4 , wherein the first part comprises a tool engagement feature with which a tool can be engaged to rotate the first part with respect to the tube.
6. The pumphead as claimed in claim 2 , wherein the retaining element comprises a threaded portion which engages with a threaded portion of the pumphead housing.
7. The pumphead as claimed in claim 4 , wherein the first part forms a passage.
8. The pumphead as claimed in claim 4 , wherein the abutment shoulder comprises a flange which provides an end face of the first part.
9. The pumphead as claimed in claim 5 , wherein the tool engagement feature is formed at an end of a passage.
10. The pumphead as claimed in claim 4 , wherein the second part forms a passage.
11. The pumphead as claimed in claim 4 , wherein the second part comprises a flange which provides an end face of the second part.
12. The pumphead as claimed in claim 4 , wherein an end face of the second part contacts an end face of the first part to seal respective passages of the first part and the second part in fluid communication with each other.
13. A method of assembling a peristaltic pumphead, comprising:
inserting a tube end of a tube into an opening of a pumphead housing;
inserting a threaded shank of an end fitting into the tube end such that the threaded shank engages with the tube;
bringing an abutment shoulder into abutting engagement with the pumphead housing; and
rotating the threaded shank with respect to the tube such that the tube is drawn along the threaded shank towards the abutment shoulder and the opening in the pumphead housing.
14. The method as claimed in claim 13 , wherein rotating the threaded shank with respect to the tube draws the tube along the threaded shank into pressing engagement with the abutment shoulder.
15. The method as claimed in claim 13 , wherein a retaining element is engaged with the end fitting to retain the end fitting against the pumphead housing.
16. The method as claimed in claim 14 , wherein a retaining element is engaged with the end fitting to retain the end fitting against the pumphead housing.
17. The method of assembling a peristaltic pumphead as claimed in claim 13 , further comprising:
engagingly receiving a tool in a tool engagement feature of the end fitting.
18. The method of assembling a peristaltic pumphead as claimed in claim 13 , wherein the end fitting comprises a first part and a second part, and wherein each of the first part and the second part form a respective through passage.
19. The method of assembling a peristaltic pumphead as claimed in claim 18 , further comprising:
placing a second part against the first part to seal the respective through passages of the first part and the second part in fluid engagement with each other.
20. The method of assembling a peristaltic pumphead as claimed in claim 19 , further comprising:
placing a cap with an inner thread over the second part; and
rotating the cap with respect to a casing that forms the opening in the pumphead housing to clamp the first part to the second part.