The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 28, 1979
Filed:
Feb. 28, 1977
James E Smith, Boulder, CO (US);
Denver Instrument Company, Denver, CO (US);
Abstract
A weight switching mechanism for a substitution type analytical balance is provided which permits the automatic selection and lifting of the required substitution weights from the gimbal assembly of a balance beam to allow accurate weighing of an unknown mass. A capacitive/electromagnetic feedback device is provided for sensing changes in the relative balance of the beam with respect to the applied unknown mass. The resultant current is applied to a force coil which maintains the beam in null position. A current related signal is converted to a digital input signal which is applied to a memory and control circuit and electronically displayed. A series of electromagnets, mounted below a printed circuit board and positioned to correspond with each substitution weight, is provided. The printed circuit board is arranged to lift upon release of the balance beam. The release of the beam causes the control circuit to selectively energize those magnets whose corresponding weights approximate the total weight of the unknown mass. The raising of the printed circuit board removes the selected weights from the gimbal assembly allowing a precise measurement of the remaining unbalance.