GB2142092A - Pump - Google Patents

Abstract

A pump comprises a filter chamber 2 which is upstream of and oriented axially to a pump impeller 4, and an annular disc 14 which separates the pumping chamber 1 from the filter chamber 2 and is connected by way of arms 13 with a cover 8 closing the filter chamber. To compensate for tolerances in the spacing of the annular disc 14 from the cover 8a sealing disc 16 of resilient material is integrally connected to the annular disc 14. <IMAGE>

Description

SPECIFICATION Pump The present invention relates to a pump, especially a washing solution pump for a washing machine.

In a liquor pump disclosed in DE-OS 21 25 747, the pressure on a seal below a screw lid is limited by placement of an annular disc on a step to a pump vane cell. Tolerances and misalignment of the seal can lead to leakage at this seal.

It would thus be desirable to compensate for irregularities in the spacing of such an annular disc from the bottom of an associated lid, wherein the flow conditions at the bore of the annular disc shall, if possible, be improved.

Accoding to the present invention there is provided a pump comprising means defining a pump chamber, an impeller arranged in the pump chamber to be rotatable about an axis, means defining a filter chamber adjacent to the pump chamber and axially upstream of the impeller, a cover element closing the filter chamber at a side thereof remote from the pump chamber, and a flow guide element disposed between the chambers and comprising an annular disc connected by arms to the cover element and a resilient sealing ring integrally connected to the annular disc and arranged to provide a seal between the chambers at the periphery of the flow guide element.

In a preferred embodiment, the pump comprises a filter chamber, which is connected in front of the pumping element and is oriented axially to a pump shaft, the chamber serving for retention of solid foreign bodies. An annular disc closes a pump vane cell off from the filter chamber and is connected through columns with a lid closing the filter chamber outwardly. A sealing ring of resilient material is integrally connected with the annular disc. Both the disc and the ring can consist of the same material, for example polyacetal. Independently of how strong a seal under the lid is pressed, and independently of length tolerances in the unitary ring and disc, the sealing ring can sit on a step to the vane cell and can bend to a greater or lesser extent.The spacing of a free sealing lip, settling on the step, of the sealing ring from the annular disc can be selected to be sufficient to accommodate all possibilities during pressing of the ring and of length tolerances.

Advantageously, the sealing ring consists of a rotational body of a slim cross-sectional surface narrowing outwardly, wherein the outer rim of the sealing ring forms the sealing lip and the inner rim of the ring is connected by an annular curved root portion with the annular disc. Advantageously, the connection at the internal circumference of the annular disc is shaped to be rounded in a manner favourable to flow so that an improvement of the flow conditions at the bore of the annular disc is achieved.

An embodiment of the present invention will now be more particularly described by way of example with reference to the accompanying drawing, which is a sectional view of a pump embodying the invention.

Referring now to the drawing, there is shown a pump comprising a vane cell 1 and a filter chamber 2 in a unitary housing, which can be connected by fastening means (not shown) to the righthand side of a motor end cover of a pump motor. A pump shaft 3 with vanes 4 projects from the motor into the cell 1.

During pumping, the vanes 4 suck water in through an axial bore 5 from the filter chamber 2 and expel it outwardly through an outlet stub pipe 6 at the circumference of the cell. The inflow into the filter chamber 2 is by way of an inlet stub pipe 7 arranged at an angle different from that of the outlet pipe 6. At the lefthand side, the filter chamber 2 is closed off by a screw lid 8, which presses a sealing ring 10 between itself and a step 9 in the filter chamber. The sealing ring 10 sits in an annular groove of conical connecting member 11, which is rotatably connected through detent elements 12 with the lid 8. The member 11 is integrally connected by way of three splayed columns or arms 13 to the annular disc 14, which at its internal circumference carries an annular curved root portion 15 of a sealing ring 16 extending flatly outwards.The sealing ring 16 rests on a step 17 to the vane cell 1 in the inserted state of the filter insert.

1. A pump comprising means defining a pump chamber, an impeller arranged in the pump chamber to be rotatable about an axis, means defining a filter chamber adjacent to the pump chamber and axially upstream of the impeller, a cover element closing the filter chamber at a side thereof remote from the pump chamber, and a flow guide element disposed between the chambers and comprising an annular disc connected by arms to the cover element and a resilient sealing ring integrally connected to the annular disc and arranged to provide a seal between the chambers at the periphery of the flow guide element.

2. A pump as claimed in claim 1, wherein the sealing ring comprises a thin-walled rotational body having a cross-sectional thickness which reduces in a radially outward direction of the ring.

3. A pump as claimed in either claim 1 or claim 2, wherein the sealing ring is connected to the annular disc by a connecting portion at the internal circumferences of the disc and ring, the connecting portion being rounded in a region thereof facing into the pump chamber.

4. A pump substantially as hereinbefore described with reference to the accompanying drawing.

5. A washing machine incorporating a pump as claimed in any one of the preceding claims, the pump being arranged to pump washing solution in the machine.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (5)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Pump The present invention relates to a pump, especially a washing solution pump for a washing machine. In a liquor pump disclosed in DE-OS 21 25 747, the pressure on a seal below a screw lid is limited by placement of an annular disc on a step to a pump vane cell. Tolerances and misalignment of the seal can lead to leakage at this seal. It would thus be desirable to compensate for irregularities in the spacing of such an annular disc from the bottom of an associated lid, wherein the flow conditions at the bore of the annular disc shall, if possible, be improved. Accoding to the present invention there is provided a pump comprising means defining a pump chamber, an impeller arranged in the pump chamber to be rotatable about an axis, means defining a filter chamber adjacent to the pump chamber and axially upstream of the impeller, a cover element closing the filter chamber at a side thereof remote from the pump chamber, and a flow guide element disposed between the chambers and comprising an annular disc connected by arms to the cover element and a resilient sealing ring integrally connected to the annular disc and arranged to provide a seal between the chambers at the periphery of the flow guide element. In a preferred embodiment, the pump comprises a filter chamber, which is connected in front of the pumping element and is oriented axially to a pump shaft, the chamber serving for retention of solid foreign bodies. An annular disc closes a pump vane cell off from the filter chamber and is connected through columns with a lid closing the filter chamber outwardly. A sealing ring of resilient material is integrally connected with the annular disc. Both the disc and the ring can consist of the same material, for example polyacetal. Independently of how strong a seal under the lid is pressed, and independently of length tolerances in the unitary ring and disc, the sealing ring can sit on a step to the vane cell and can bend to a greater or lesser extent.The spacing of a free sealing lip, settling on the step, of the sealing ring from the annular disc can be selected to be sufficient to accommodate all possibilities during pressing of the ring and of length tolerances. Advantageously, the sealing ring consists of a rotational body of a slim cross-sectional surface narrowing outwardly, wherein the outer rim of the sealing ring forms the sealing lip and the inner rim of the ring is connected by an annular curved root portion with the annular disc. Advantageously, the connection at the internal circumference of the annular disc is shaped to be rounded in a manner favourable to flow so that an improvement of the flow conditions at the bore of the annular disc is achieved. An embodiment of the present invention will now be more particularly described by way of example with reference to the accompanying drawing, which is a sectional view of a pump embodying the invention. Referring now to the drawing, there is shown a pump comprising a vane cell 1 and a filter chamber 2 in a unitary housing, which can be connected by fastening means (not shown) to the righthand side of a motor end cover of a pump motor. A pump shaft 3 with vanes 4 projects from the motor into the cell 1. During pumping, the vanes 4 suck water in through an axial bore 5 from the filter chamber 2 and expel it outwardly through an outlet stub pipe 6 at the circumference of the cell. The inflow into the filter chamber 2 is by way of an inlet stub pipe 7 arranged at an angle different from that of the outlet pipe 6. At the lefthand side, the filter chamber 2 is closed off by a screw lid 8, which presses a sealing ring 10 between itself and a step 9 in the filter chamber. The sealing ring 10 sits in an annular groove of conical connecting member 11, which is rotatably connected through detent elements 12 with the lid 8. The member 11 is integrally connected by way of three splayed columns or arms 13 to the annular disc 14, which at its internal circumference carries an annular curved root portion 15 of a sealing ring 16 extending flatly outwards.The sealing ring 16 rests on a step 17 to the vane cell 1 in the inserted state of the filter insert. CLAIMS

1. A pump comprising means defining a pump chamber, an impeller arranged in the pump chamber to be rotatable about an axis, means defining a filter chamber adjacent to the pump chamber and axially upstream of the impeller, a cover element closing the filter chamber at a side thereof remote from the pump chamber, and a flow guide element disposed between the chambers and comprising an annular disc connected by arms to the cover element and a resilient sealing ring integrally connected to the annular disc and arranged to provide a seal between the chambers at the periphery of the flow guide element.

2. A pump as claimed in claim 1, wherein the sealing ring comprises a thin-walled rotational body having a cross-sectional thickness which reduces in a radially outward direction of the ring.

3. A pump as claimed in either claim 1 or claim 2, wherein the sealing ring is connected to the annular disc by a connecting portion at the internal circumferences of the disc and ring, the connecting portion being rounded in a region thereof facing into the pump chamber.

4. A pump substantially as hereinbefore described with reference to the accompanying drawing.

5. A washing machine incorporating a pump as claimed in any one of the preceding claims, the pump being arranged to pump washing solution in the machine.