Abstract: A needle-carrying head for a printing machine has needles controlled by electro-magnets. The coils of the electro-magnets are soldered to pins carried by support ears for the coils. The pins pass through printed circuit boards to which they are soldered. The coils are engaged on cores constituted by limbs of respective fork-shaped members the second limb of which serves to complete the magnetic circuit. The two limbs of each fork-shaped member are interconnected by means of a transverse portion constituting a yoke, secured by setting into one or the other of two plates forming, with a central plate made of plastics material, a cage-shaped frame of the needle-carrying head. The printed circuit boards are thus interposed between the electro-magnets and the front plate of the frame on the one hand, and between the electro-magnets and the rear plate on the other hand.

Abstract: A character-carrying disc for a printing machine has a central hole surmounted by a circular portion which is situated out of the plane of a body of the disc and supported at a distance from the body of the disc by two diametrically opposed pillars. This circular portion is provided with two diametrically opposed ears enabling the disc to be gripped. The circular portion of the disc is provided with two small tongues which are elastically deformable and are directed axially, with free ends of the tongues being movable in two openings provided in the body of the disc. The small tongues are adapted to press resiliently on the shaft of the printing machine on which the disc is mounted for the purpose of retaining the disc in place on this shaft.

Abstract: A radially displaceable coupling between a printing disc and the drive shaft of a printing machine. A bracket having a planar surface is secured to the drive shaft, the bracket having a planar face. Clamps are provided on one of the disc and bracket faces for engagement with the other of said disc and face. A resilient arm, including a zig-zag configured portion terminating in a blade having an inclined lateral surface, is formed on one of the disc and bracket and a recess is provided in the other of the disc and bracket for receiving the resilient arm to effect securement therein in a wedgelike engagement. A lateral surface borders the recess and coacts with the lateral blade surface. The lateral surfaces are convergent relatively coacting when the arm is engaged within the recess to prevent angular movement of the disc and to cause the disc to bear against the drive shaft at a location diametrically opposite to the location of the recess.

Abstract: A method of manufacturing the molded hub of a print wheel of the type having a central axial passage of precise diameter and a plurality of elastically deformable, concentrically arranged character carrying radial arms. A metal ring carrying radial passageways is centered in the mold cavity used for forming the hub, etc., and a plastics composition is injected into the mold cavity only through the center of the ring and by way of the radial passageways whereby the metal ring becomes a unitary permanent part of the hub and defines the central axial passage. After the molding, the molded structure is released from the mold and the remainent central plastic plug easily is sheared from the ring, as by punching, for example. Remainent plastic material left within the radial passageways functions supplementary to maintain the stability and concentricity of the ring and hub assembly.

Abstract: A characters carrying aggregate or assembly for a printing machine includes a characters carrying disk carrying the characters on the outer ends of radial arms extending from the disk. The disk is mounted on a hub and may include a crown mounted opposite the hub. The assembly is manufactured on a base plate having at least two positioning pins corresponding to two positioning holes in the disk. The base-plate includes a central hole or protrusion for aligning with a central protrusion or hole in the hub. The base-plate further includes an alignment finger which extends through an orientation hole in the disk into a specific oriented alignment with an orientation hole in the hub. The aligned hub and disk are then secured together.