Peristaltic Pump

Abstract

A peristaltic pump for conveying fluids includes a stator and a rotor supported therein. A flexible hose is integrated in the stator and the rotor includes radially arranged conveying elements which squeeze the hose over a section containing the fluid. The squeezed fluid section moves progressively in the hose under the effect of a motor connected to the rotor. The conveying elements are designed as rotatably mounted rollers that include at least two rolling bearings, of which the outer rings are connected via a common outer sleeve and of which the inner rings are connected to the rotor. Under the effect of the motor, the rotor moves in the stator and the outer rings of the conveying elements roll on the inner surface of the stator.

Description

BACKGROUND AND SUMMARY OF THE INVENTION

The invention relates to a peristaltic pump for conveying fluids, comprising a stator and a rotor supported therein, wherein a flexible hose is integrated in the stator and the rotor comprises radially arranged conveying elements which squeeze the hose over a section containing the fluid, and wherein the squeezed fluid section moves progressively in the hose under the effect of a motor connected to the rotor.

A peristaltic pump is a positive displacement pump in which the medium to be conveyed is pushed through a hose by the external mechanical deformation thereof. German Patent Document DE 10 2008 002 761 A1 discloses an example of such a pump. A drawback of these pumps the high frictional forces occurring between the hose and the conveying elements when the hose is squeezed. As a result of these increased frictional forces, both the transmission driving the rotor of the peristaltic pump and the hose itself are subjected to heavy loading.

Exemplary embodiments of the present invention are directed to a peristaltic pump having a long service life, in which the transmission and conveying medium hose are prevented from becoming damaged during operation.

The peristaltic pump according to the invention comprises a stator and rotor supported therein, wherein a flexible hose is integrated in the stator, and the rotor comprises radially arranged conveying elements which squeeze the hose over a section containing the fluid, and wherein the squeezed fluid section moves progressively in the hose under the effect of a motor connected to the rotor. According to the invention, the conveying elements are designed as rotatably mounted rollers which comprise at least two rolling bearings, of which the outer rings are connected via a common outer sleeve and of which the inner rings are connected to the rotor, wherein, under the effect of the motor, the rotor moves in the stator and the outer rings of the conveying elements roll on the inner surface of the stator.

Rolling bearings, also known as ball bearings, are bearings in which two components that are movable relative to one another, namely the “inner ring” and the “outer ring”, are separated by rolling bodies. They are used to support radial and axial forces in axles and shafts and are intended to minimize the power loss and wear caused by friction. Rolling friction primarily occurs between the three main components, the inner ring, outer ring and rolling bodies. Since the rolling bodies in the inner and outer rings roll on hardened steel surfaces with optimized lubrication, the rolling friction of these bearings is relatively low.

BRIEF DESCRIPTION OF THE DRAWING FIGURES

The invention will be explained in greater detail hereinafter with reference to figures, in which

FIG. 1 is a schematic view of a pump head of a peristaltic pump according to the invention,

FIG. 2 is a view along the sectional line A-A in FIG. 1 of a conveying means according to the invention.

DETAILED DESCRIPTION

FIG. 1 shows a peristaltic pump 1 for conveying fluids. The peristaltic pump comprises a stator 4, in which a flexible hose 3 is integrated over a substantially circular path (approximately 360°). As is illustrated in FIG. 1 by the arrow, a rotor 5 is supported in the stator 4. The rotor has radially arranged conveying elements 2a, 2b, 2c. The conveying elements 2a, 2b squeeze the hose 3 in the section 10. A motor, not illustrated in greater detail, cooperates with the rotor 5 and, in particular, moves the squeezed fluid section 10 progressively in the hose 3 in accordance with the direction of the arrow. The fluid is thus conveyed in the section 10 from the inlet E of the peristaltic pump 1 to the outlet A of the pump 1. Of course, conveyance may also occur in a direction opposite that of the arrow. In this case the peristaltic pump 1 may be used both for pumping and for suction.

The hose 3 is fixed in a hose clamp 9 in the region of the inlet E and of the outlet A of the pump 1, wherein the hose clamp 9 is connected to the stator 4.

The conveying hose 3 is surrounded and guided almost completely by the stator 4. A valve function of the pump 1 is thus achieved. If the rotor 5 is idle, at least two conveying elements 2 press the hose 3 so that the path for the fluid is blocked.

FIG. 2 shows a sectional view along the sectional line A-A in FIG. 1 of a conveying element 2 of the pump according to the invention. The conveying element 2 comprises two rolling bearings 6a, 6b. Each rolling bearing 6a, 6b consists of an inner ring 8a and an outer ring 7a. The rolling bodies 11 are located between the inner ring 8a and the outer ring 7a. The inner rings 8a of the two rolling bearings 6a, 6b are connected rigidly to one another and to the rotor 5. The outer rings 7a of the two rolling bearings 6a, 6b are interconnected and form a type of outer sleeve 7 of the conveying element 2. There is no connection between the rotor 5 and the outer sleeve 7. It is thus ensured that the outer sleeve 7 is mounted rotatably about the axis D.

FIG. 2 also shows the stator 4 and the hose 3 squeezed between the stator 4 and the outer sleeve 7.

The bearings 6a, 6b are connected to a common outer sleeve 7, which prevents tilting of the outer rings 7a of the rolling bearings. In addition, the pump can be adapted to different hose thicknesses or pumping pressures by varying the thickness of the outer sleeve 7. Moreover, the outer sleeve 7 provides the hose 3 with a smooth outer surface. This increases the service life of the rolling bearings 6a, 6b, of the hose 3 and of the transmission. During pumping or suction operation of the pump 1, each conveying element 2a, 2b, 2c thus rolls on the hose 3 with virtually no frictional forces.

The foregoing disclosure has been set forth merely to illustrate the invention and is not intended to be limiting. Since modifications of the disclosed embodiments incorporating the spirit and substance of the invention may occur to persons skilled in the art, the invention should be construed to include everything within the scope of the appended claims and equivalents thereof.

Claims

1-3. (canceled)

4. A peristaltic pump for conveying fluids, comprising:

a stator with an integrated flexible hose;

a rotor supported in the stator, wherein the rotor comprises radially arranged conveying elements configured to squeeze the hose over a section containing the fluid, and wherein the squeezed fluid section moves progressively in the hose under the effect of a motor connected to the rotor,

wherein the conveying elements are rotatably mounted rollers comprising at least two rolling bearings, of which outer rings are connected via a common outer sleeve and inner rings are connected to the rotor, and

wherein, under the effect of the motor, the rotor moves in the stator and the outer rings of the conveying elements roll on the inner surface of the stator.

5. The peristaltic pump as claimed in claim 4, wherein the hose extends within the stator over a substantially circular path.

6. The peristaltic pump as claimed in claim 4, wherein the hose is arranged in a region of an inlet to and of an outlet from the peristaltic pump with a common hose clamp that is connected to the stator.