Apparatus for calculating the price of measured lengths of material

Claim 1

Apparatus for calculating the price of a measured length of material comprising: means for sensing movement in either of two directions of a material having a length to be measured and a price per unit length, the sensing means including a light source, a pair of detectors responsive to the presence or absence of light and a disk responsive to the movement of material in either direction and having first and second optically encoded bands respectively interposed along optical paths from the light source to the detectors alternately to block and transmit light from said source to said respective detectors in a phased sequence which is a function of the direction of movement of the material, said optically encoded bands comprising concentric rings of alternating opaque and light-transmitting zones with the positions of the zones in the first band being shifted with respect to the positions of the zones in the second band whereby as the disk is rotated by the movement of the material the sequence of transmission and interruption of light by the first band relative to that of the second band differs in phase as a function of the direction of movement of the material, and first and second roll means for the insertion therebetween of said material whose length is to be measured and to which the disk is coupled whereby the direction of rotation of the roll means as a material moves therebetween in either direction determines the direction of rotation of the disk; means into which the unit price of the material is entered and from which a binary value related thereto may be derived; logic means responsive to the sensing means for determining the direction of material movement and for providing a first signal representative of the distance of the material moves in a forward direction and a second signal representative of the distance the material moves in a reverse direction; means responsive to the first and second signals and to the binary value derived from the unit price to provide an output signal representing the total price of the measured length of material, said signal responsive means including a length counter whose contents are incremented in response to the first signal and decremented in response to the second signal whereby the contents of the length counter represent the binary value of the total measured length of material and means responsive to the end of a bolt of material passing through the roll means to provide an indication thereof, said bolt end responsive means further including switch means for incrementing the contents of the length counter an amount equal to an offset between the roll means and a predetermined reference point at which said material is initially aligned; and display means responsive to the output signal for indicating the total price of a measured length of material.