US4350186A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Gravimetric diluter
Assignee: Spiral Biotech Inc
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Filing: 1981-02-09
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Granted: 1982-09-21
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Expires: 2001-02-09
Abstract
Abstract An apparatus for making dilutions of a sample with a diluent to a predetermined dilution factor f by weight of the diluent is disclosed. A scale with TARE capability produces an output signal of the weight W of a sample within a container less the weight of the container. A dilution factor control is provided for setting the predetermined dilution factor f. Means are provided for calculating and storing the value TW=W/f which is the total weight of the sample plus the weight of the diluent which is required to dilute the sample to the predetermined dilution factor f. A pump is connected between a reservoir of diluent and the container for the sample for pumping the amount of diluent into the container which is required to dilute the sample to the predetermined weight dilution factor f. The scale provides a continuous output of the weight W of the sample plus diluent in the container at any instant in time. Means are provided for calculating when TW-W=0. In one embodiment, the flow of diluent to the container is stopped by the stopping of the pump when TW-W=0. In another embodiment, the flow of diluent to the container is stopped by closing a pair of valves located between the pump and the container when TW-W=0.
Inventors
- 👤 Samuel Schalkowsky
- 👤 Donald Whitley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 15:30
CPC Classifications
G; G01; G01N; G01N1/00; G01N1/28; G01N1/38; G01N35/00; G01N2035/00178; G01N2035/00207; G01N2035/00217
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
170 words
An apparatus for diluting a sample within a container to a dilution factor f by weight of diluent comprising: (a) means for repeatedly measuring the weight W of the sample plus any diluent within the container; (b) means for choosing a dilution factor f by weight of a diluent to be used for diluting the sample; (c) means for calculating TW wherein TW=W/f and W is the weight of the sample within the container prior to the addition of diluent; (d) means for calculating TW-W; (e) fluid conducting means disposed between a reservoir of diluent and the container for permitting the diluent to flow from the reservoir to the container for the purpose of diluting the sample within the container to the selected dilution factor f; and (f) means responsive to the means for calculating TW-W for controlling the flow of diluent between the reservoir and the container to cause diluent to flow between the container and the reservoir when TW>W and to stop the flow of diluent when TW=W.
Claim 2
Independent Claim
170 words
An apparatus for diluting a sample within a container to a dilution factor f by weight of diluent comprising: (a) means for repeatedly measuring the weight W of the sample plus any diluent within the container; (b) means for choosing a dilution factor f by weight of a diluent to be used for diluting the sample; (c) means for calculating TW wherein TW=W/f and W is the weight of the sample within the container prior to the addition of diluent; (d) means for calculating TW-W; (e) fluid conducting means disposed between a reservoir of diluent and the container for permitting the diluent to flow from the reservoir to the container for the purpose of diluting the sample within the container to the selected dilution factor f; and (f) means responsive to the means for calculating TW-W for controlling the flow of diluent between the reservoir and the container to cause diluent to flow between the container and the reservoir when TW>W and to stop the flow of diluent when TW=W.
Claim 3
Dependent Claim
17 words
The apparatus of claim 1 wherein the means responsive to the means for calculating is a pump.
Claim 4
Dependent Claim
12 words
The apparatus of claim 2 wherein the pump is a peristalic pump.
Claim 5
Dependent Claim
41 words
The apparatus of claim 1 further comprising: (a) means for calculating when TW-W=C where C is a predetermined weight and wherein (b) the means for controlling maintains a higher flow rate when TW-W>C and a lesser rate of flow when TW-W≦C.
Claim 6
Dependent Claim
35 words
The apparatus of claim 4 wherein the means for controlling is a pump having two specified rates of flow, the pump pumping at the higher rate when TW-W>C and at the lower rate when TW-W>C.
Claim 7
Dependent Claim
12 words
The apparatus of claim 5 wherein the pump is a peristaltic pump.
Claim 8
Independent Claim
174 words
An apparatus for diluting a sample within a container to a dilution factor f by weight of diluent comprising: (a) means for repeatedly measuring the weight W of the sample plus any diluent within the container; (b) means for choosing a dilution factor f by weight of a diluent to be used for diluting the sample; (c) means for calculating TW wherein TW=W/f and W is the weight of the sample within the container prior to flow the addition of diluent; (d) means for comparing TW and W; (e) fluid conducting means disposed between a reservoir of diluent and the container for permitting the diluent to from the reservoir to the container for the purpose of diluting the sample within the container to the selected dilution factor f; and (f) means responsive to the means for comparing TW and W for controlling the flow of diluent between the reservoir and the container to cause diluent to flow between the container and the reservoir when TW>W and to stop the flow of diluent when TW=W.
Claim 9
Independent Claim
174 words
An apparatus for diluting a sample within a container to a dilution factor f by weight of diluent comprising: (a) means for repeatedly measuring the weight W of the sample plus any diluent within the container; (b) means for choosing a dilution factor f by weight of a diluent to be used for diluting the sample; (c) means for calculating TW wherein TW=W/f and W is the weight of the sample within the container prior to flow the addition of diluent; (d) means for comparing TW and W; (e) fluid conducting means disposed between a reservoir of diluent and the container for permitting the diluent to from the reservoir to the container for the purpose of diluting the sample within the container to the selected dilution factor f; and (f) means responsive to the means for comparing TW and W for controlling the flow of diluent between the reservoir and the container to cause diluent to flow between the container and the reservoir when TW>W and to stop the flow of diluent when TW=W.
References Cited (Backward Citations)
US3263761A
Cited
US3254728A
Cited
US3398689A
Cited
US3528518A
Cited
US3516506A
Cited
US3805141A
Cited
US3959636A
Cited
US4222448A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-09-20 | 1986-03-22 | 1986-09-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-09-20 | 1990-03-22 | 1990-09-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-09-20 | 1994-03-22 | 1994-09-21 | $7700.00 | Window Closed / Lapsed |