Method for operating a peristaltic pump
First Claim
1. A method for operating a peristaltic pump, the peristaltic pump comprising:
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a flexible tube for guiding a liquid to be pumped, —
a compression mechanism being actuatable for compressing the flexible tube, —
an upstream valve mechanism arranged in an upstream direction with respect to the compression mechanism and being actuatable to selectively open or close the flexible tube upstream of the compression mechanism and —
a downstream valve mechanism arranged in a downstream direction with respect to the compression mechanism and being actuatable to selectively open or close the flexible tube downstream of the compression mechanism, wherein a drive mechanism periodically actuates the compression mechanism, the upstream valve mechanism, and the downstream valve mechanism; and
a pressure sensor measures a pressure and outputs a pressure signal indicative of a pressure in the flexible tube at a location between the upstream valve mechanism and the downstream valve mechanism, wherein, for detecting a fault condition, —
a first signal value indicative of a pressure value downstream of the downstream valve mechanism and a second signal value indicative of a pressure value upstream of the upstream valve mechanism are computed from the measured pressure signal, —
a threshold value is computed from the first signal value and the second signal value, and —
the measured pressure signal or at least one signal parameter derived from the measured pressure signal is compared with the threshold value to detect the fault condition; and
wherein the threshold value is computed as the mean value of the first signal value and the second signal value, multiplied by a correction factor;
wherein in the case of detecting the fault condition, an alarm is triggered to indicate the fault condition.
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Accused Products
Abstract
A peristaltic pump comprises a flexible tube, a compression mechanism being actuatable for compressing the flexible tube, an upstream valve mechanism being actuatable to selectively open or close the tube upstream of the compression mechanism and a downstream valve mechanism being actuatable to selectively open or close the tube downstream of the compression mechanism. A drive mechanism actuates the compression mechanism, the upstream and downstream valve mechanisms. A pressure sensor measures a pressure signal indicative of a pressure in the tube between the upstream and downstream valve mechanisms. First and second signal values indicative of a pressure value downstream the downstream valve mechanism and upstream the upstream valve mechanism, respectively, are computed from the measured pressure signal. A threshold value is computed from the first and second signal values, and the measured pressure signal or a derived signal parameter is compared with the threshold value to detect a fault condition.
18 Citations
11 Claims
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1. A method for operating a peristaltic pump, the peristaltic pump comprising:
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a flexible tube for guiding a liquid to be pumped, —
a compression mechanism being actuatable for compressing the flexible tube, —
an upstream valve mechanism arranged in an upstream direction with respect to the compression mechanism and being actuatable to selectively open or close the flexible tube upstream of the compression mechanism and —
a downstream valve mechanism arranged in a downstream direction with respect to the compression mechanism and being actuatable to selectively open or close the flexible tube downstream of the compression mechanism, wherein a drive mechanism periodically actuates the compression mechanism, the upstream valve mechanism, and the downstream valve mechanism; and
a pressure sensor measures a pressure and outputs a pressure signal indicative of a pressure in the flexible tube at a location between the upstream valve mechanism and the downstream valve mechanism, wherein, for detecting a fault condition, —
a first signal value indicative of a pressure value downstream of the downstream valve mechanism and a second signal value indicative of a pressure value upstream of the upstream valve mechanism are computed from the measured pressure signal, —
a threshold value is computed from the first signal value and the second signal value, and —
the measured pressure signal or at least one signal parameter derived from the measured pressure signal is compared with the threshold value to detect the fault condition; and
wherein the threshold value is computed as the mean value of the first signal value and the second signal value, multiplied by a correction factor;
wherein in the case of detecting the fault condition, an alarm is triggered to indicate the fault condition. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8)
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9. A peristaltic pump, comprising:
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a flexible tube for guiding a liquid to be pumped, —
a compression mechanism being actuatable for compressing the flexible tube, —
an upstream valve mechanism arranged in an upstream direction with respect to the compression mechanism and being actuatable to selectively open or close the flexible tube upstream of the compression mechanism, —
a downstream valve mechanism arranged in a downstream direction with respect to the compression mechanism and being actuatable to selectively open or close the flexible tube downstream of the compression mechanism, —
a drive mechanism for periodically actuating the compression mechanism, the upstream valve mechanism, and the downstream valve mechanism, —
a pressure sensor for measuring a pressure and outputting a pressure signal indicative of a pressure in the flexible tube at a location between the upstream valve mechanism and the downstream valve mechanism, and —
a controller to control the operation of the peristaltic pump, the controller being operative to detect a fault condition during the operation of the peristaltic pump from the measured pressure signal, wherein the controller, for detecting the fault condition, is operative —
to compute from the measured pressure signal a first signal value indicative of a pressure value downstream of the downstream valve mechanism and a second signal value indicative of a pressure value upstream of the upstream valve mechanism, —
to compute a threshold value from the first signal value and the second signal value, the threshold value being computed as the mean value of the first signal value and the second signal value, multiplied by a correction factor and —
to compare the measured pressure signal or at least one signal value derived from the measured pressure signal with the threshold value to detect the fault condition;
wherein in the case of detecting the fault condition, an alarm is triggered to indicate the fault condition. - View Dependent Claims (10, 11)
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Specification