Method and apparatus for simultaneously following a plurality of outlines

Claim 3

A method as claimed in claim 1 comprising the step of selecting the longitudinal movement signal which has the lowest magnitude, and driving the line followers at a speed directly related to the said magnitude.

Claim 4

A method as claimed in claim 1 comprising selecting the transverse Movement signal having the highest magnitude, and driving the line followers at a speed related by an inverse function to the said magnitude.

Claim 5

Apparatus for simultaneously following a plurality of outlines for the purpose of guiding separate tools comprising a carriage bearing a plurality of photoelectric line followers each adapted to follow a separate outline and deliver movement signals, means for mounting the line followers so that they travel simultaneously in a longitudinal direction while allowing each line follower to make independent transverse movements to follow the respective outline, means to receive movement signals from all the line followers and to compare the movement signals continuously, means for continuously selecting whichever movement signal corresponds to the slowest longitudinal movement, and means to vary the longitudinal speed of the carriage continuously in dependence upon the magnitude of the selected movement signal.

Claim 6

Apparatus for simultaneously following a plurality of outlines for the purpose of guiding separate tools comprising a carriage bearing a plurality of photoelectric line followers each adapted to follow a separate outline and deliver movement signals, means for mounting the line followers so that they travel simultaneously in a longitudinal direction while allowing each line follower to make independent transverse movements to follow the respective outline, means to receive movement signals from all the line followers and to compare the movement signals continuously, means for continuously selecting whichever movement signal corresponds to the slowest longitudinal movement, and means to vary the longitudinal speed of the carriage continuously in dependence upon the magnitude of the selected movement signal.

Claim 7

Apparatus as claimed in claim 4 in which the signals are all longitudinal movement signals, the signal selecting means being responsive to the signal of smallest magnitude.

Claim 8

Apparatus as claimed in claim 4 in which the signals are all transverse movement signals, the signal selecting means being responsive to the signal of largest magnitude, the means to control the speed of the line followers comprising means to control the longitudinal speed according to an inverse function of the selected signal.

Claim 9

Apparatus as claimed in claim 4 in which the movement signals are electrical signals, comprising electronic means to compare the magnitudes of the movement signals in order to select the signal corresponding to the slowest longitudinal movement.

Claim 10

Apparatus as claimed in claim 7 comprising a transistor circuit for each signal, the signal being applied to the respective transistor base, diode means in the collector circuit of each transistor, all the diode means being connected together so that at any instant all the diode means except that associated with the selected signal are reverse biased.

Claim 13

A method as claimed in claim 9 comprising the step of detecting the reverse longitudinal movement signal by its changed phase with respect to the phase of the forward movement signals.

Claim 14

Apparatus for simultaneously following a plurality of outlines for the purpose of guiding separate tools comprising a primary carriage capable of longitudinal movement, at least one secondary carriage capable of forward movement with and reverse movement with respect to the primary carriage, at least one photoelectric line follower capable of delivering movement signals mounted on the primary carriage for movement therewith, an additional photoelectric line follower capable of delivering movement signals mounted on the secondary carriage, means included in the mountings of all the line followers to enable each line follower to make independent transverse movements in order to follow the respective outline, means to cause the primary and secondary carriages to move forward simultaneously while all the line followers are producing forward longitudinal movement signAls, means to detect the production of a reverse movement signal by the said additional line follower, means responsive to the reverse movement signal to stop the forward movement of the primary carriage while the secondary carriage preforms the reverse movement, and means to restart the forward movement of the primary and secondary carriages when the said additional line follower again produces a forward movement signal.

Claim 15

Apparatus for simultaneously following a plurality of outlines for the purpose of guiding separate tools comprising a primary carriage capable of longitudinal movement, at least one secondary carriage capable of forward movement with and reverse movement with respect to the primary carriage, at least one photoelectric line follower capable of delivering movement signals mounted on the primary carriage for movement therewith, an additional photoelectric line follower capable of delivering movement signals mounted on the secondary carriage, means included in the mountings of all the line followers to enable each line follower to make independent transverse movements in order to follow the respective outline, means to cause the primary and secondary carriages to move forward simultaneously while all the line followers are producing forward longitudinal movement signAls, means to detect the production of a reverse movement signal by the said additional line follower, means responsive to the reverse movement signal to stop the forward movement of the primary carriage while the secondary carriage preforms the reverse movement, and means to restart the forward movement of the primary and secondary carriages when the said additional line follower again produces a forward movement signal.

Claim 16

Apparatus as claimed in claim 11 comprising means to compare the magnitudes of the movement signals and to select the movement signal corresponding to the slowest forward movement, and means to drive the primary and secondary carriages forward at a speed dependent upon the magnitude of the selected signal.

Claim 17

A modification of the apparatus claimed in claim 11, in which the means responsive to the reverse movement signal causes the speed of forward movement of the primary carriage to be reduced to a low level while the secondary carriage performs the reverse movement.