Abstract: For the controlled slowdown of a translatory or rotary machine part to arrest same in a predetermined stop position of an entrained load, the part being driven by an electric motor against a countervailing torque, a trial run is used with a constant motor torque (less than the countervailing torque) to determine a deceleration characteristic under conditions duplicating those of a subsequent production run. The deceleration characteristic is registered in the form of discrete positional values detected at successive instants, these values being stored in a memory for consecutive readout at corresponding instants in a production run and comparison with actual load positions to provide an error signal for the adjustment of the motor torque. A specific embodiment serves to control the final position of a rotary workpiece holder in friction welding.

Abstract: A manipulator drive has a main support defining a main longitudinal axis, a housing rotatable on the main support about the main longitudinal axis, a head defining a head longitudinal axis and rotatable on the housing about an outer transverse axis crossing the main longitudinal axis, and a holder rotatable on the head about the head longitudinal axis. Respective housing, head, and holder stepdown drive transmissions have outputs connected directly to the housing, head, and holder and inputs and have stepdown transmission ratios of at least 70:1.

Abstract: A first succession of workpieces is displaced along a first conveyor path past a work station in steps and a second succession of workpieces is displaced past the work station in steps synchronously with the first succession along a second conveyor path crossing the first path at an intersection adjacent the work station. The workpieces of the first and second successions are alternately arrested adjacent the work station so that as a workpiece of one succession is arrested adjacent the station the workpieces of the other succession are moving and vice versa. A tool at the station works alternately on the arrested workpieces. Thus as a workpiece of one succession is being held stationary and worked on a workpiece of the other succession is being removed from adjacent the station and replaced with the following workpiece of the other succession. The workpieces are transported horizontally generally at the same level and the paths cross at the intersection generally at a right angle.

Abstract: Two coaxially aligned workpieces of ferromagnetic material, axially separated by a narrow peripheral gap across which a weld seam is to be formed with the aid of an arc moving along that gap, are engaged by holders including at least one set of two or more ferromagnetic gripper jaws whose confronting faces are magnetized with like polarity by respective excitation windings surrounding extensions of these jaws. The resulting magnetic field extends axially within the workpiece held by the gripper jaws in a loop which passes generally radially through the peripheral gap, either on account of a bucking magnetic field (which may be generated by a similar set of jaws gripping the other workpiece) or by virtue of pole shoes of the opposite polarity juxtaposed with the jaw extensions and approaching the gap.

Abstract: A tool holder for a manipulator comprises a tool shaft extending along and rotatable about a main axis and having a tool-shaft end provided with a pivot defining a transverse axis. A tool is carried on the pivot and is displaceable relative to the tool shaft about the transverse axis. A stack of guide rings coaxially surrounds the tool shaft adjacent the pivot and is formed with at least two throughgoing guide-ring passages each having a radially outwardly opening passage end. Two of the guide rings define a pair of axially spaced annular confronting guide-ring surfaces. A connector ring is rotatable on the stack between the guide-ring surfaces and has a pair of axially oppositely directed connector-ring surfaces one of which axially directly confronts one of the guide-ring surfaces. A connector element secures the connector ring to the tool-shaft end for joint rotation of same about the main axis.

Abstract: An industrial robot, designed to machine a workpiece by means of a tool supported on an extremity of a mobile arm, is controlled by a programmer whose memory is initially loaded with a preliminary program including the locations of a multiplicity of closely juxtaposed but discrete points on the workpiece surface and instructions for the guidance of that extremity establishing rectilinear or circularly arcuate paths between these points. With the tool replaced by a sensor contacting a pattern corresponding to the desired shape of the workpiece, the preliminary program is executed and deviations from the established paths are registered to modify the stored instructions, thereby converting the preliminary program into a definite program subsequently used in shaping the actual workpiece.

Abstract: A pivot drive for interconnecting a pair of members that are relatively pivotal about a pivot axis has a torsion rod extending along a rod axis and rotatable by an appropriate drive relative to one of the members. This rod has outer ends carrying input gears of respective constant-mesh gear trains having output gears at least one of which is limitedly rotatable about the pivot axis on the other member. This one output gear can be limitedly rotated and locked in place in the other member so as torsionally to prestress the rod, thereby eliminating play from the drive by bringing the gears of one of the gear trains into snug contact in one direction and the gears of the other gear train into snug contact in the opposite directions.