Machine for performing operations consecutively at preselected working positions

Claim 2

A machine for performing operations consecutively at preselected working positions, comprising: a carrier member; at least one moving means for said carrier member; a drive system to move said moving means in either direction along a co-ordinate axis; a scale extending along said co-ordinate axis, said scale comprising a plurality of transverse conductive strips insulated from adjacent strips; said moving means including a shortcircuiting member adapted to short-circuit any two adjacent strips of its scale in the direction of movement of said moving means; an electronic logic circuit; detector means in said logic circuit to detect a short-circuit between the two adjacent strips in registration with a preselected working position; and means in said logic circuit initiating stopping of said drive system at the commencement of said short-circuit and restarting said drive system in the opposite sense after a predetermined time interval, to provide accurate iterative positioning of said moving system in registration with said preselected working position.

Claim 3

A machine according to claim 1 in which said logic circuit produces a square-wave signal of predetermined duration at connections to two adjacent strips of said scale, in response to short-circuiting of said adjacent strips; and said logic circuit effects stopping of said drive system in response to the rising leading edge of said square-wave signal, and operation of said drive system in the opposite sense in response to the falling trailing edge of said square-wave signal.

Claim 4

A machine according to claim 2 in which said scale includes an insulating support and said conductive strips of said scale project from said support; and said short-circuiting member comprises a roller at Least the rolling surface of which is conductive and which is operatively connected to said moving means to be moved over said scale in the direction of said co-ordinate axis.

Claim 5

A machine according to claim 5 in which the radius of said roller is so related to the width of the gap between said two adjacent strips that, even after wear of the contact edges of said adjacent strips, said roller contacts only said strips and not said insulating support.

Claim 6

A machine according to claim 3 in which said roller is mounted on a spindle with a clearance so related to the width of the gap between said two adjacent strips and to the speed of movement of said roller that said roller makes a short-circuit of predetermined duration between said strips.

Claim 7

A machine according to claim 1 in which each said two adjacent strips represent a position data bit; and which includes a sub-circuit interconnecting said strips and said logic circuit to encode said position data.

Claim 8

A machine according to claim 6 in which some of said conductive strips of said scale are arranged in the form of two interdigitated combs, each of said strips which forms one tooth of either of said combs being disposed between two strips not belonging to the same comb.

Claim 9

A machine according to claim 6 in which said interconnections correspond to decimal-coded binary encoding.

Claim 10

A machine according to claim 8 in which said conductive strips are numbered from 0; the even-number strips are in the form of two half-strips insulated from one another; the odd-number strips are interconnected in groups of five consecutive strips to decade output connections; and said 0-strip and said half-strips are connected to ten unit output connections, the first strip or half-strip being connected to the first of said unit output connections, the second strip or half-strip being connected to the second of said unit output connections, and so on.

Claim 11

A machine according to claim 1 in which said scale, at both ends of said plurality of strips which constitute a working zone, has further strips; and in which there are connections from said further strips to said logic circuit to control at least the braking of said drive system to prevent said moving means moving out of said working zone.

Claim 12

A machine according to claim 1 in which said scale has a plurality of rows of strips connected in the same order to said logic circuit, each said row providing positioning to a different pitch.

Claim 13

A machine according to claim 1 in which said logic circuit includes comparator means for comparing the co-ordinate of any working position with the co-ordinate of the immediately previously working position, and means for controlling the movement of said drive system in the sense appropriate to such comparison.

Claim 14

An electronic circuit wiring machine for performing wiring operations consecutively at predetermined working positions identified by co-ordinates from two perpendicular co-ordinate axes; comprising a wiring tool carrier member; two slide means for said carrier member movable respectively parallel to said co-ordinate axes; two drive systems, respectively to move each said slide means in either direction parallel to the respective co-ordinate axis; a scale extending along each of said co-ordinate axes, each of said scales compring a plurality of transverse conductive strips each insulated from adjacent strips; each said slide means including a short-circuiting member adapted to short-circuit any two adjacent strips of its associated scale in the direction of movement of said slide means; an electronic logic circuit; detector means in said logic circuit to detect short-circuits between the two adjacent strips in registration with a preselected working position; and means in said logic circuit initiating stopping of said drive systems at the commencement of said short-circuit and restarting said drive systems in the opposite sense after a predetermined time interval, to provide accurate iterative positioning of sAid slide means in registration with said preselected working position.

Claim 15

An electronic circuit wiring machine for performing wiring operations consecutively at predetermined working positions identified by co-ordinates from two perpendicular co-ordinate axes; comprising a wiring tool carrier member; two slide means for said carrier member movable respectively parallel to said co-ordinate axes; two drive systems, respectively to move each said slide means in either direction parallel to the respective co-ordinate axis; a scale extending along each of said co-ordinate axes, each of said scales compring a plurality of transverse conductive strips each insulated from adjacent strips; each said slide means including a short-circuiting member adapted to short-circuit any two adjacent strips of its associated scale in the direction of movement of said slide means; an electronic logic circuit; detector means in said logic circuit to detect short-circuits between the two adjacent strips in registration with a preselected working position; and means in said logic circuit initiating stopping of said drive systems at the commencement of said short-circuit and restarting said drive systems in the opposite sense after a predetermined time interval, to provide accurate iterative positioning of sAid slide means in registration with said preselected working position.

Claim 16

An electronic circuit wiring machine according to claim 13, in which at least one of said two scales has two rows of strips, providing two different pitches.