Method of fine adjusting balances and balance for performing this method

Claim 3

A method according to claim 1, wherein each said display unit d equals ten measuring units m.

Claim 4

An automatically fine adjusting digitally indicating balance, measuring and computing in measuring units m and indicating in display units d where d is a multiple of m, comprising in combination: a vibrating string balance with two transversely vibrating strings coupled to a weighing platform and forming a Vee pretensioned by the weight of a mass, where the respective frequencies of said vibrating strings are a function of a load to be measured on the weighing platform; two sensors, one coupled to each of said vibrating strings, each providing an electrical A.C. signal, the frequency of which corresponds to the frequency of the associated vibrating string; a computing means electrically connected to said sensors for determining in digital form in said measuring units m the load on said weighing platform using the transmitted frequencies of said two vibrating strings as input information to perform said determination; a zero range circuit coupled to the output of said computing means to detect whether the number of output pulse falls within a predetermined zero range of measuring units m, which zero range consists of as many measuring units less one as are equal to one display unit d; a standstill control unit for checking whether the load is steady, comprising two counters and coincidence circuitry, the steadiness of the load being ascertained by the comparison of the number of pulses generated by one of said vibrating strings during two consecutive measuring periods, wherein said standstill control circuit generates a signal when the number of pulses measured during each of said consecutive measuring periods are found to coincide; a first AND gate, connected to the outputs of said zero range circuit and said standstill control circuit, respectively; a second AND gate, connected to the outputs of the computing means and said first AND gate, respectively, wherein said computing means transmits the number of pulses corresponding to an empty weighing platform upon the simultaneous positive findings of said zero range circuit and said standstill control circuit; a first arithmetic unit, connected to the output of the second AND gate, for deducting a preDetermined number of counts from the number of counts transmitted by said computing means, said predetermined number of counts being equal to half the multiple of measuring units m corresponding to one display unit d; a storage device, connected to the output of said arithmetic unit, for storing the result of the deduction performed in said first arithmetic unit; a second arithmetic unit, connected to the outputs of the computing means and the storage device, respectively, for deducting said result stored in said storage device from the number of counts transmitted by the computing means, corresponding to the load on the weighing platform; digital display means connected to the output of said second arithmetic unit, said display means displaying the number of counts divided by the number of measuring units m corresponding to one display unit d, transmitted by said second arithmetic unit; and a manually operated coarse adjustment means comprising a tare weight shiftable in discrete steps to provide additional coarse adjusting capability when said predetermined range of counts is outside the range of said zero range control circuit when no load is on the weighing platform.

Claim 5

An automatically fine adjusting digitally indicating balance, measuring and computing in measuring units m and indicating in display units d where d is a multiple of m, comprising in combination: a vibrating string balance with two transversely vibrating strings coupled to a weighing platform and forming a Vee pretensioned by the weight of a mass, where the respective frequencies of said vibrating strings are a function of a load to be measured on the weighing platform; two sensors, one coupled to each of said vibrating strings, each providing an electrical A.C. signal, the frequency of which corresponds to the frequency of the associated vibrating string; a computing means electrically connected to said sensors for determining in digital form in said measuring units m the load on said weighing platform using the transmitted frequencies of said two vibrating strings as input information to perform said determination; a zero range circuit coupled to the output of said computing means to detect whether the number of output pulse falls within a predetermined zero range of measuring units m, which zero range consists of as many measuring units less one as are equal to one display unit d; a standstill control unit for checking whether the load is steady, comprising two counters and coincidence circuitry, the steadiness of the load being ascertained by the comparison of the number of pulses generated by one of said vibrating strings during two consecutive measuring periods, wherein said standstill control circuit generates a signal when the number of pulses measured during each of said consecutive measuring periods are found to coincide; a first AND gate, connected to the outputs of said zero range circuit and said standstill control circuit, respectively; a second AND gate, connected to the outputs of the computing means and said first AND gate, respectively, wherein said computing means transmits the number of pulses corresponding to an empty weighing platform upon the simultaneous positive findings of said zero range circuit and said standstill control circuit; a first arithmetic unit, connected to the output of the second AND gate, for deducting a preDetermined number of counts from the number of counts transmitted by said computing means, said predetermined number of counts being equal to half the multiple of measuring units m corresponding to one display unit d; a storage device, connected to the output of said arithmetic unit, for storing the result of the deduction performed in said first arithmetic unit; a second arithmetic unit, connected to the outputs of the computing means and the storage device, respectively, for deducting said result stored in said storage device from the number of counts transmitted by the computing means, corresponding to the load on the weighing platform; digital display means connected to the output of said second arithmetic unit, said display means displaying the number of counts divided by the number of measuring units m corresponding to one display unit d, transmitted by said second arithmetic unit; and a manually operated coarse adjustment means comprising a tare weight shiftable in discrete steps to provide additional coarse adjusting capability when said predetermined range of counts is outside the range of said zero range control circuit when no load is on the weighing platform.

Claim 6

A balance according to claim 3, wherein the manually operated coarse adjustment means are adjusted in steps of half as many measuring units m as are equal to one display unit d.

Claim 7

A balance according to claim 3, wherein one display unit d equals ten measuring units m.