Analog/digital meter having front indicator means overlying a rear indicator means

Claim 2

An analog/digital meter comprising, a rear readout indicator, a front readout indicator overlying the rear readout indicator, said front readout indicator including a generally transparent indicator structure adapted to be inactivated to provide a substantially unobstructed view of the rear indicator through the transparent indicator structure or be activated to provide a readout which may be read in addition to the readout of the rear readout indicator, the other readout indicator being an analog indicator operable for displaying an analog readout, and an indicator operating circuit operable by variable input electrical signal means through an established range of value thereof for operating the digital and analog indicators for respectively displaying numerical and analog readouts corresponding to the value of the input electrical signal means, the indicator operating circuit comprising control means for selectively activating and inactivating the front readout indicator.

Claim 3

An analog/digital meter according to claim 1 wherein the front indicator is a liquid crystal indicator.

Claim 4

An analog/digital meter according to claim 1 wherein the operating circuit comprises manual switch means for manually selectively activating and deactivating the front readout indicator to display its readout.

Claim 5

An analog/digital meter according to claim 1 wherein the analog readout indicator comprises an analog needle, a needle actuator operable by the operating circuit for positioning the analog needle in accordance with the value of said input electrical signal means, and a calibrated scale mounted behind the path of movement of the needle.

Claim 6

An analog/digital meter according to claim 4 further comprising a magnet mounted on the needle and a magnetic pickup head settable along a path adjacent the path of movement of the needle and operable by the magnet as it moves into operative alignment therewith for generating a predetermining electrical signal.

Claim 7

An analog/digital meter according to claim 5 wherein the analog needle is pivotally mounted and the magnetic pickup head is pivotally mounted coaxially with the analog needle.

Claim 8

An analog/digital meter comprising front and rear contiguous readout indicators having respectively a front generally transparent visual readout area and a rear visual readout area underlying the front generally transparent readout area, one of the readout indicators being a digital indicator operable for displaying in its readout area any numerical readout within a multiple place range, the other readout indicator being an analog indicator operable for displaying an analog readout in its readout area, and an indicator operating circuit operable by varIable input electrical signal means through an established range of value thereof for operating the digital and analog indicators for respectively displaying numerical and analog readouts corresponding to the value of the input electrical signal means, the readout area of the analog indicator being directly behind the readout area of the digital indicator and the readout area of the digital indicator being formed by a window which is generally transparent when the digital indicator is not operated to display a numerical readout, the analog indicator comprising an analog needle, a needle actuator operable by the operating circuit for positioning the analog needle in accordance with the value of said input electrical signal means, a calibrated scale mounted behind the path of movement of the needle, a magnet mounted on the needle and a magnetic pickup head settable along a path adjacent the path of movement of the needle and operable by the magnet as it moves into operative alignment therewith for generating a predetermining electrical signal, the operating circuit being operable by the predetermining electrical signal for operating the digital indicator to display said numerical readout.

Claim 9

An analog/digital meter comprising front and rear contiguous readout indicators having respectively a front generally transparent visual readout area and a rear visual readout area underlying the front generally transparent readout area, one of the readout indicators being a digital indicator operable for displaying in its readout area any numerical readout within a multiple place range, the other readout indicator being an analog indicator operable for displaying an analog readout in its readout area, and an indicator operating circuit operable by varIable input electrical signal means through an established range of value thereof for operating the digital and analog indicators for respectively displaying numerical and analog readouts corresponding to the value of the input electrical signal means, the readout area of the analog indicator being directly behind the readout area of the digital indicator and the readout area of the digital indicator being formed by a window which is generally transparent when the digital indicator is not operated to display a numerical readout, the analog indicator comprising an analog needle, a needle actuator operable by the operating circuit for positioning the analog needle in accordance with the value of said input electrical signal means, a calibrated scale mounted behind the path of movement of the needle, a magnet mounted on the needle and a magnetic pickup head settable along a path adjacent the path of movement of the needle and operable by the magnet as it moves into operative alignment therewith for generating a predetermining electrical signal, the operating circuit being operable by the predetermining electrical signal for operating the digital indicator to display said numerical readout.

Claim 10

An analog/digital meter according to claim 1 wherein the control means comprises predetermining means operable in conjunction with the analog readout indicator for automatically operating the digital readout for displaying the numerical readout at a predetermined analog readout of the analog readout.