US5058422A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electronic balance
Assignee: Shimadzu Corp
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Filing: 1990-07-12
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Granted: 1991-10-22
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Expires: 2010-07-12
Abstract
Abstract Method and apparatus for calibrating the sensitivity and linearity of the weighing means of an electronic balance, wherein a sensitivity calibration is automatically conducted when the ambient temperature has changed a first predetermined amount or a predetermined period of time has passed since the previous calibration was conducted, and when a sensitivity calibration is conducted, it is checked whether or not the temperature change has exceeded a second predetermined amount greater than the first predetermined amount, and only when the temperature change has exceeded the second predetermined amount since the previous linearity calibration was conducted, a linearity calibration is conducted along with the sensitivity calibration.
Inventors
- 👤 Kunio Shimauchi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 04:01
CPC Classifications
G; G01; G01G; G01G23/00; G01G23/01; G01G23/012
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
108 words
A method of calibrating the sensitivity and linearity of the weighing means of an electronic balance, comprising the steps of: automatically conducting a sensitivity calibration when the ambient temperature has changed a first predetermined amount since the previous sensitivity calibration was conducted or when a predetermined period of time has passed since the previous sensitivity calibration was conducted; determining whether said ambient temperature has changed at least a second predetermined amount since the previous linearity calibration was conducted, said second predetermined amount being greater than said first predetermined amount; and conducting a linearity calibration only when said ambient temperature has changed by at least said second predetermined amount.
Claim 2
Independent Claim
108 words
A method of calibrating the sensitivity and linearity of the weighing means of an electronic balance, comprising the steps of: automatically conducting a sensitivity calibration when the ambient temperature has changed a first predetermined amount since the previous sensitivity calibration was conducted or when a predetermined period of time has passed since the previous sensitivity calibration was conducted; determining whether said ambient temperature has changed at least a second predetermined amount since the previous linearity calibration was conducted, said second predetermined amount being greater than said first predetermined amount; and conducting a linearity calibration only when said ambient temperature has changed by at least said second predetermined amount.
Claim 3
Dependent Claim
95 words
The method of claim 1, wherein said electronic balance includes a pair of calibration weights and a mechanism for loading and unloading said calibration weights on and from said weighing means; and wherein said sensitivity calibration is conducted by renewing a sensitivity coefficient of said weighing means based on measurement data obtained from said weighing means when said pair of calibration weights are simultaneosly loaded on said weighing means, measurement data obtained from said weighing means when no load is applied to said weighing means, and the actual mass of said pair of calibration weights.
Claim 4
Dependent Claim
101 words
The method of claim 1, wherein said electronic balance includes a pair of calibration weights and a mechanism for loading and unloading said calibration weights on and from said weighing means; and wherein said linearity calibration is conducted by renewing a coefficient for linearity calibration based on measurement data obtained from said weighing means when said pair of calibration weights are loaded simultaneously on said weighing means, measurement data obtained from said weighing means at a zero point, and data at an intermediate point obtained from individual data obtained when each of said calibration weights is loaded on said weighing means.
Claim 5
Dependent Claim
152 words
An electronic balance comprising: weighing means including a load sensor for weighing a load; temperature sensor means for detecting the ambient temperature of said load sensor; a plurality of built-in calibration weights; means for loading and unloading said calibration weights on and from said load sensor; means for indicating the mass of an object being measured; and control means for automatically conducting a sensitivity calibration of said load sensor when said ambient temperature has changed a first predetermined amount or a predetermined period of time has passed since the previous calibration was conducted, and for determining whether said ambient temperature has changed at least a second predetermined amount since a previous linearity calibration was conducted, said second predetermined amount being greater than said first predetermined amount, and for conducting a calibration of the linearity of said load sensor only when said ambient temperature has changed by at least said second predetermined amount.
Claim 6
Dependent Claim
152 words
An electronic balance comprising: weighing means including a load sensor for weighing a load; temperature sensor means for detecting the ambient temperature of said load sensor; a plurality of built-in calibration weights; means for loading and unloading said calibration weights on and from said load sensor; means for indicating the mass of an object being measured; and control means for automatically conducting a sensitivity calibration of said load sensor when said ambient temperature has changed a first predetermined amount or a predetermined period of time has passed since the previous calibration was conducted, and for determining whether said ambient temperature has changed at least a second predetermined amount since a previous linearity calibration was conducted, said second predetermined amount being greater than said first predetermined amount, and for conducting a calibration of the linearity of said load sensor only when said ambient temperature has changed by at least said second predetermined amount.
Claim 7
Dependent Claim
65 words
The electronic balance of claim 4, wherein said controller conducts a sensitivity calibration by renewing a sensitivity coefficient of said weighing means by measurement data obtained from said weighing means when said calibration weights are simultaneously loaded on said weighing means, measurement data obtained from said weighing means when no load is applied to said weighing means, and the actual mass of said calibration weights.
Claim 8
Dependent Claim
74 words
The electronic balance of claim 4, wherein said controller conducts a linearity calibration by renewing a coefficient for linearity calibration by measurement data obtained from said weighing means when said calibration weights are loaded simultaneously on said weighing means, measurement data obtained from said weighing means at a zero point, and measurement data at an intermediate point obtained from individual data obtained when each of said calibration weights is loaded on said weighing means.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-10-21 | 1995-04-22 | 1995-10-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-10-21 | 1999-04-22 | 1999-10-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-10-21 | 2003-04-22 | 2003-10-22 | $7700.00 | Window Closed / Lapsed |