HOSE PUMP AND DEVICE FOR ANALYSING A CHEMICAL OR BIOLOGICAL SAMPLE

Abstract

Hose pump with a hose for taking up the fluid to be pumped and with a planetary gear rack having a ring gear, a sun gear and at least two planetary gears interposed between the ring gear and the sun gear, wherein at least one of the teeth of the planetary gear during one cycle of the planetary gear around the sun gear at least once engages with the hose to squeeze a portion of the hose.

Claims

1. Hose pump (1) with a hose (2) for taking up the fluid to be pumped and with a planetary gear rack (3) having a ring gear (4), a sun gear (5) and at least two planetary gears (6) interposed between the ring gear (4) and the sun gear (5), characterized in that at least one of the teeth (7) of the planetary gear (6) during one cycle of the planetary gear (6) around the sun gear (5) at least once engages with the hose (2) to squeeze a portion of the hose (2).

2. Hose pump according to claim 1, characterized by a support surface, the portion of the hose (2) being squeezed between the tooth (7) of the planetary gear (6) and the support surface (10).

3. Hose pump according to claim 1 or 2, characterized in that the ring gear (4) is a ring segment and that the ring gear (4) instead of a further ring segment that would complete the ring gear (4) to a ring has an opening (9), a portion of the hose (2) being arranged inside this opening (9).

4. Hose pump according to claim 3, characterized in that the ring segment of the ring gear (4) spans over more than 180°.

5. Hose pump according to claim 3 or 4, characterized in that the ring segment of the ring gear (4) spans over less than an angle is calculated by 360° minus an enclosure angle, the enclosure angle being calculated by the formula:
enclosure angle=360°/number of planetary gears (6) of the planetary gear rack (3).

6. Hose pump according to any one of claims 1 to 5, characterized in that the planetary gear in the direction of its rotational axis extends over the ring gear and that the portion of the planetary gear that extends over the ring gear engages into the hose to squeeze a portion of the hose.

7. Hose pump according to any one of claims 1 to 6, characterized in that a position sensor is arranged at the planetary gear or at the cage to determine the rotational position of the planetary gear in the planetary gear rack.

8. A device for analysing a sample, said device comprising at least one depot chamber and at least one process chamber, whereas the process chamber is integrated in at least one first support member and the depot chamber is integrated in at least a second support member, whereas the support members are arranged in that the process chamber is connectable with the depot chamber by a relative movement of the first and second support members with respect to each other, the device further comprising a pump element for transferring the substances inside the device from one chamber to another, characterized in that the pump element is a hose pump (1) according to any one of claims 1 to 7.

9. System comprising: a hose pump (1) according to any one of claims 1 to 7 or a device according to claim 8 a base station, said base station comprising at least a pump drive which acts on the hose pump (1) to drive the planetary gear around the sun gear.

10. System according to claim 9, characterized in that the hose pump according to any one of claims 1 to 7 or the device according to claim 8 is detachably connected to the base station.

11. Use of the hose pump (1) according to any one of claims 1 to 7 or of the device according to claim 8 or of the system according to one of the claims 9 to 10 and in the field of point-of-care applications, in particular in the field of nucleic acid analysis.

Description

[0042] Below, the invention will be described with reference to figures that only show specific embodiments. The only FIGURE shows a cartridge that contains a hose pump according to the invention in a schematic side view.

[0043] The hose pump (1) shown in the FIGURE has a hose (2) for taking up the fluid to be pumped. The hose pump (1) also has a planetary gear rack (3) with a ring gear (4), a sun gear (5), and five planetary gears (6) interposed between the ring gear (4) and the sun gear (5) and held by a cage.

[0044] In the moment of operation shown in the FIGURE, six of the teeth (7) of one of the planetary gears (6) are in engagement with the hose (2) and squeeze a portion of the hose. This can be seen from the FIGURE; the engagement of the teeth (7) with the hose leads to the channel within the hose (2) being completely blocked. The hose's walls are in this particular moment at point (8).

[0045] As can be seen from the FIGURE, the ring gear is a ring segment. Instead of a further ring segment that would complete the ring gear (4) to a ring, the ring gear (4) has an opening (9). A portion of the hose (2) is arranged inside this opening (9). The opening spans over an angle a that in the embodiment shown in the FIGURE is approximately 115°. Consequently, the ring segment of the ring gear spans over an angle of 245° (360°-α).

[0046] The hose pump (1) is provided with a support surface (10) that has a bent shape. This allows the portion of the hose (2) that is in contact with the support surface (10) to take up the shape of a ring segment. This ring segment spans over an angle β of approximately 90°.

[0047] The opening of the ring gear and the ring segment of the hose span over an angle that is larger than an enclosure angle, which is defined to be =360°/number of planetary gears of the planetary gear rack. The enclosure angle in the embodiment shown in the FIGURE, which has five planetary gears of the planetary gear rack, is 72°. The opening spans are α=115°. Since β equals 90° and is thus larger than 72°, the design shown in the FIGURE ensures that in every instant of time at least one of the planetary gears is in engagement with a portion of the hose, and that for the number of degrees that β is larger than the enclosure angle, namely for approximately 18°, two planetary gears are in engagement with the portion of the hose. This prevents the back flow of fluid from being pumped through the channel of the hose (2).

[0048] Given that the opening (9) of the ring gear (4) spans over an angle α=115°, and given that the hose (2) takes the shape of a ring segment over an angle of approximately 90°, the embodiment shown in the FIGURE shows an embodiment where the angle that the ring segment shaped portion of the hose (2) takes up is approximately 80% of the angle that the opening (9) takes up (β/α equals 90°/115°=80%).