During grinding, a grinding wheel effects movements of solely vertical displacement along a path parallel to a vertical guide rod. The workpiece to be machined is held by a rotatable, but not axially displaceable, chuck secured to a workpiece head. In order that helical relative movements between the workpiece and the grinding wheel may be produced, transmission components and gearing are provided for positively converting the vertical motion of the grinding wheel into rotary motion of the workp...

A centering device is provided in a spring core mounting machine having at least one pair of clamping jaws for holding together the terminal windings of adjacent helical springs while they are being connected by threading wire helices through them, with the terminal windings of the helical springs being provided at two diametrically oppositely located portions with bent-out zones in which the spring wire extends at least approximately in a straight line and in parallelism with the opposite zone....

A pipe cutter for cutting the wall of a pipe from within the bore of the pipe. The cutter includes a blade and mechanisms for supporting the blade within the pipe to be cut, urging the blade outwardly of the pipe to engage it with the pipe wall and moving the blade relative to the pipe so that the blade cuts the wall. The cutter may include an expansible gripper assembly for engaging the pipe wall to retain the blade against movement axially of the pipe during the cutting operation. The gripper ...

Clampable apparatus for producing convex and/or concave spherical surfaces such as optical lenses, comprising a frame, a swivel arm in the form of a gantry and mounted on the frame such that its angle of inclination relative thereto is adjustable, the swivel arm including two spaced apart support portions, a rocker arm pivotally and adjustably mounted on an axle extending between the support portions, the rocker arm having a spindle sleeve housing axially displaceably mounted thereon, the housin...

A coin wrapper cutting tool comprising a principal body portion on which a cutting blade for cutting crimped end portions of wrappers of packaged rolls of coins and an element for shielding the blade when cutting is not required are assembled; the principal body portion including at least one shoulder supporting the blade and shielding element, the shoulder also having a side beyond which the blade projects. The principal body portion also including a platform portion extending from a back side ...

A multistation blast processing machine has a conveyor formed as a wheel (2) for workpieces (6) held in several receiving chambers (5) by means of holding devices (13, 13a). Two workpieces (6) are held in axially spaced relationship in each chamber and are conveyed by cyclic rotation of the wheel (2) to two blast processing stations (8, 8a) and into one loading and discharging station (7). The chambers (5) distributed evenly over the periphery are separated by walls (9) attached to the wheel (2)...

A method for lapping two flats of substantially the same dimensions in an element having a cone-shaped tip. The method includes the steps of contacting a first region of the cone wherein a flat is to be lapped while the cone is in contact with the lapping surface; rotating the element to a second region wherein a second flat is to be lapped while the tip is in contact with the lapping surface without the cone tip contacting or disturbing the lapping surface; contacting the second region of the c...

The cleaning apparatus includes a wheel in the form of a rapidly rotating drum having relatively few blades spaced circumferentially about the periphery thereof and extending radially thereon. Abrasive material is delivered from a hopper through a slot and is picked up by the blades of the rapidly rotating drum and delivered with extremely high kinetic energy into the surface to be cleaned. The apparatus is constructed so that the recovery path of the abrasive material from the surface to be cle...

A method of finishing a glass surface to a close tolerance and a substantially blemish-free state using a moving polishing lap and an aqueous treatment liquid containing inert abrasive particles, in which the treatment liquid also contains a bifluoride which reacts with the glass to form an insoluble silicofluoride or fluoride, an acid supplying hydrogen ions and a solubility suppressant which ensures that the silicofluoride or fluoride separates out on the glass surface, whereby the lap and ine...

A machine for grinding threads on a workpiece which is rotated in a workhead while the workhead is reciprocated by a table under a grinding wheel to form threads in the workpiece. To improve the accuracy with which the threads are formed, the workpiece and a grinding wheel dresser contact the grinding wheel on the same side of the wheel at points which are symmetrical to and on opposite sides of the centerline of the wheel which extends parallel to the path along which the wheel is fed into the ...