Determining tip seal maintenance requirement in scroll pump
AssigneeAgilent Technologies, Inc.
InventorJohn Calhoun
Life of this patent
Estimating the term…
Abstract
A scroll pump or pumping system is configured to determine whether tip seals of the scroll pump require maintenance such as replacement. During operation of the scroll pump, pump inlet pressure is measured or calculated over a recent time period to acquire recent pump data. The recent pump data is compared to historical pump data, which is or includes pump inlet pressure measured over a historical time period preceding the recent time period. Based on the comparison, a determination is made as to whether tip seal maintenance for the scroll pump and/or further diagnosis of the scroll pump is required. If so, a user-interpretable output may be produced, indicating that tip seal maintenance and/or further diagnosis is required.
Claims20
A method for assessing scroll pump tip seal wear, the method comprising:
- providing a dry scroll pump comprising:
- a pump inlet;
- a pump outlet;
- a pumping stage comprising a first scroll and a second scroll nested together, wherein the first scroll is configured to orbit about a drive axis relative to the second scroll to pump fluid from the pump inlet to the pump outlet, and the second scroll is fixedly positioned in an axial direction relative to the drive axis;
- a first scroll tip seal mounted to the first scroll;
- and a second scroll tip seal mounted to the second scroll;
- providing historical pump data comprising historical values of pump inlet pressure over a historical time period;
- operating the scroll pump to pump the fluid, wherein the operating is done during a recent time period preceded by the historical time period;
- during the operating, determining pump inlet pressure to acquire recent pump data comprising recent values of pump inlet pressure over the recent time period;
- comparing the recent pump data and the historical pump data;
- and
- based on the comparing, determining that tip seal maintenance for the scroll pump and/or further diagnosis of the scroll pump is required.
A dry scroll pump, comprising:
- a pump inlet;
- a pump outlet;
- a dry pumping stage comprising a first scroll and a second scroll nested together, wherein the first scroll is configured to orbit about a drive axis relative to the second scroll to pump fluid from the pump inlet to the pump outlet, and the second scroll is fixedly positioned in an axial direction relative to the drive axis;
- a first scroll tip seal mounted to the first scroll;
- a second scroll tip seal mounted to the second scroll;
- a sensor configured to measure pump inlet pressure or to measure an operating parameter from which the pump inlet pressure can be calculated;
- and
- a controller configured to assess tip seal wear, by controlling or performing an operation comprising:
- providing historical pump data comprising historical values of pump inlet pressure over a historical time period;
- operating the scroll pump to pump the fluid, wherein the operating is done during a recent time period preceded by the historical time period;
- during the operating, determining pump inlet pressure to acquire recent pump data comprising recent values of pump inlet pressure over the recent time period;
- comparing the recent pump data and the historical pump data;
- and
- based on the comparing, determining that tip seal maintenance for the scroll pump and/or further diagnosis of the scroll pump is required.
Dependencies are inferred from the claim text.