Patents Assigned to Erowa AG
  • Patent number: 5242359
    Abstract: The manufacturing plant comprises at least one manufacturing cell provided with at least one processing device, a handling device associated with the processing device in order to automatically exchange tools and/or workpieces on the processing device, and a magazine for the objects to be handled arranged in the reach of the handling device. The magazine is provided with a rotating rack having a plurality of storing planes mounted upon another on a support. The manufacturing plant comprises a plurality of such rotating racks. The rotating racks are designed as separate transportable constructional units which are exchangeably inserted in a stationary part of the magazine. The stationary part comprises means for rotating the rotating rack. The manufacturing plant further comprises a transfer station separate from the manufacturing cell for loading and unloading the rotating racks. Transporting means, e.g.
    Type: Grant
    Filed: June 3, 1992
    Date of Patent: September 7, 1993
    Assignee: Erowa AG
    Inventor: Basil Obrist
  • Patent number: 5201502
    Abstract: An apparatus for clamping workpieces which have to be machined by a machine tool. The apparatus comprises a rectangular frame including two longitudinal frame members and two transverse frame members. Clamping means are provided to fix the workpieces to be machined to said rectangular frame. The clamping means comprise at least one auxiliary frame which is removably inserted in said rectangular frame. Each of the auxiliary frames includes two clamping bars which can be adjustably connected to each other and the ends thereof being adapted to be connected to the longitudinal frame members of the rectangular frame such that they are adjustable in the longitudinal direction of the longitudinal frame. The clamping bars comprise a plurality of continuous threaded bores running essentially perpendicular to the clamping bars, said bores being enlarged to a predetermined nominal diameter and said bores being adapted to selectively receive a clamping screw.
    Type: Grant
    Filed: August 28, 1991
    Date of Patent: April 13, 1993
    Assignee: Erowa AG
    Inventor: Rudolf Schneider
  • Patent number: 5134346
    Abstract: The driving apparatus for the rotation of the spindle or the work piece pallet of an electroerosive machining device comprises two electric motors which drive e.g. the spindle to a rotational movement by means of two gear boxes and a plurality of gear wheels. In order to avoid any backlash in the gear box and any clearance between the gear wheels and to compensate the elasticity of the gear transmission, the two electric motors are always operated to rotate in opposite directions and/or to yield different values of torque. Thus, the entire transmission assembly is always subjected to a certain bias force so that a precise positioning of the spindle is possible by means of simple and inexpensive driving elements.
    Type: Grant
    Filed: September 7, 1989
    Date of Patent: July 28, 1992
    Assignee: Erowa AG
    Inventors: Rudolf Schneider, Niklaus Liechti
  • Patent number: 5074731
    Abstract: The invention provides a screw nut comprising a central inner thread and a radially extending slit, the width thereof essentially corresponding to the diameter of the central inner thread. Thus, a threaded bolt or a threaded stud can be radially inserted into said screw nut body. In order to avoid that the screw nut is displaced away from the threaded bolt or stud during tightening of the screw nut, the central inner thread comprises a plurality of thread turns provided with axially extending recesses directed towards the end surface of the screw nut which is under load when the screw nut is tightened on the threaded bolt or stud.
    Type: Grant
    Filed: July 5, 1990
    Date of Patent: December 24, 1991
    Assignee: Erowa AG
    Inventor: Rudolf Schneider
  • Patent number: 5065991
    Abstract: The invention provides an apparatus for fixing a workpiece to be machined by a machine tool to the worktable of the machine tool in an exactly determined positional relationship with reference to a reference point located on the worktable of the machine tool. The apparatus of the invention comprises a workpiece receiving means adapted to removably receive the workpiece to be machined, and first positioning means comprising a first group of positioning apertures provided in the workpiece receiving means, and a first group of positioning studs provided on the worktable of the machining tool, said first group of positioning apertures and said first group of positioning studs cooperating to determine the position of the workpiece receiving means in X- and Y-direction.
    Type: Grant
    Filed: June 6, 1990
    Date of Patent: November 19, 1991
    Assignee: Erowa AG
    Inventor: Rudolf Schneider
  • Patent number: 4934680
    Abstract: The invention provides a manufacturing jig to precisely position a workpiece with reference to a workpiece receiving means. The jig comprises a workpiece supporting member to which the workpiece is fixed and a receiving member on which said workpiece supporting member is releasably mounted. The receiving member comprises two registering pins protruding from one surface thereof. The workpiece supporting member comprises two centering apertures adapted to engage the two registering pins upon mounting the workpiece supporting member on the receiving member. The two centering apertures are located distantly to each other. The first centering aperture has a fixed position with reference to the workpiece supporting member and the second centering aperture is displaceable with reference to the workpiece supporting member in a direction along a tie line between the centers of the first and second centering apertures, but movable in a direction running perpendicular to said tie line.
    Type: Grant
    Filed: September 1, 1988
    Date of Patent: June 19, 1990
    Assignee: Erowa AG
    Inventor: Rudolf Schneider
  • Patent number: 4853512
    Abstract: A spark erosion machining apparatus with an electrode changing mechanism having electrode support members and a frame that are connected to the interior front wall of the tub that can be opened like a door Two pairs of levers are pivotally mounted on the frame. The free ends of the levers have a transverse beam with perpendicularly protruding electrode support members. The transverse beams with the electrode support members can be pivoted (using hydraulic or pneumatic cylinder pistons) from a rest position where they are near to the front wall of the tub into an operating position where the electric support members are in an essentially central portion of the tub.
    Type: Grant
    Filed: July 1, 1988
    Date of Patent: August 1, 1989
    Assignee: Erowa AG
    Inventor: Rudolf Scheider
  • Patent number: 4845835
    Abstract: The invention refers to a tool or workpiece storing magazine incorporating a tool- or workpiece-change apparatus adapted to remove a tool or a workpiece from the magazine and to transport the it into a machining apparatus, and to remove a tool or workpiece from the machining apparatus and to transport it back to the storing magazine, respectively. The system comprises a plurality of essentially disc-shaped tool or workpiece supporting members rotatably and coaxially arranged with reference to a first axis of rotation which receive and support a plurality of tools or workpieces along the periphery thereof. A transport arm is pivotally mounted on a second axis of rotation and longitudinally displaceable along said second axis located in a certain distance from said first axis of rotation. The transport arm is adjustable with reference to its length and includes a gripping member mounted on its free end. The transport arm further includes a turning knuckle, the axis thereof extending in an angle of 45.degree.
    Type: Grant
    Filed: June 14, 1988
    Date of Patent: July 11, 1989
    Assignee: Erowa AG
    Inventor: Rudolf Schneider
  • Patent number: 4815780
    Abstract: The invention provides an apparatus for detachably connecting a tool to a manipulating device, e.g. an industrial robot. The apparatus includes a tool holder and a coupling member fastened to the robot. The coupling member has a free frontal surface on which the tool holder rests. A plurality of air channels and electric contacts merge into the free frontal surface in a peripheral region thereof. Four projecting centering pins are provided in the center of the free frontal surface. The tool holder is provided with correspondingly located air channels and electric contacts as well as with a centrally arranged centering disc which is rigid in circumferential direction and axially resilient. The disc has apertures in which the centering pins enter when the tool holder is fixed to the coupling member. Thus, the tool holder is precisely centered and all pneumatic and electric connections are automatically established.
    Type: Grant
    Filed: March 22, 1988
    Date of Patent: March 28, 1989
    Assignee: Erowa AG
    Inventor: Basil Obrist
  • Patent number: 4790078
    Abstract: The measuring apparatus comprises a base plate member including a rotatable measuring object receiving station adapted to rotatably receive e.g. a tool to be measured. Besides the receiving station, a guiding column is arranged having a guiding rail along which a measuring carriage is movable upwardly and downwardly. The carriage is provided with a horizontally displaceable measuring rail, an end portion thereof being equipped with a measuring calliper assembly. This assembly includes a measuring calliper with a calliper head which may be brought into contact with the tool to be measured. The calliper head is displaceable with regard to a calliper portion fixed to the end portion of the measuring rail. A force acting on the calliper head in horizontal direction (e.g. towards the right) causes the same displacement of the calliper head as a force acting on the calliper head in vertical direction (e.g. upwardly). The displacement is determined by means of a measuring gauge.
    Type: Grant
    Filed: January 28, 1987
    Date of Patent: December 13, 1988
    Assignee: Erowa AG
    Inventor: Rudolf Schneider
  • Patent number: 4759245
    Abstract: The invention refers to a tool assembly for cuttingly machining of an at least partially closed inner surface of a workpiece, e.g. a bore. It comprises an essentially rod-shaped tool support having a machining tool mounted on its end and which is adapted to be inserted into the cavity to be machined. The tool support comprises a rod member with a continuous opening extending in axial direction and with parallel supporting surfaces arranged in the region of the both ends and extending with an angle to the longitudinal axis of the rod member. A machining tool supporting member having a machining tool mounted at one end is slidably mounted at one end of the rod member and rests against the first supporting surfaces of the rod member. A control member is slidably mounted at the other end of the rod member perpendicularly to the axis of the tool support and resting on the second supporting surface, serving for the pushing-out and retiring of the tool supporting member.
    Type: Grant
    Filed: May 6, 1985
    Date of Patent: July 26, 1988
    Assignee: Erowa AG
    Inventor: Rudolf Schneider
  • Patent number: 4686768
    Abstract: The measuring calliper provides for the determination of two perpendicular linear dimensions of a workpiece by means of the same measuring apparatus. It comprises a calliper body consisting of two portions which are displaceable with reference to each other. A calliper head, which is engageable with the workpiece to be measured and is operatively coupled to the measuring apparatus, is mounted on a first portion. The second portion is connected to the first portion by means of elastically resilient connection members which extend at an angle of 45.degree. with reference to the measuring directions. Preferably, the calliper body is a one-piece construction and is subdivided into said first and second portions by means of slots provided in the calliper body and extending at an angle of 45.degree..
    Type: Grant
    Filed: September 22, 1986
    Date of Patent: August 18, 1987
    Assignee: Erowa AG
    Inventor: Rudolf Schneider
  • Patent number: 4621821
    Abstract: The invention provides a clamping apparatus, particularly for receiving and clampingly retaining electrode body blanks having prismatic or circular cross section for erosive machining devices. A clamping block has at one of its surfaces an essentially centrally arranged clamping chamber to receive the electrode. Two adjacent walls of the clamping chamber are provided with clamping screws protruding into the clamping chamber. An approximately central position of the workpiece in the clamping chamber is achieved by the provision of distance plates with preselectable thickness, which are inserted into the clamping chamber between two walls thereof and the surface of the workpiece, before the workpiece is clamped by tightening the clamping screws. This clamping apparatus is inexpensive and rugged, so that the electrode, once machined and used, respectively, may always remain clamped and therefore may be used again with a very high precision as far as its position is concerned.
    Type: Grant
    Filed: September 21, 1984
    Date of Patent: November 11, 1986
    Assignee: Erowa AG
    Inventor: Rudolf Schneider
  • Patent number: 4615688
    Abstract: The invention provides a coupling device with a first, driven member and a second member to be driven by the first member to a rotational movement. A driving plate is arranged between the two members and fixedly connected to the second member. In order to provide an angularly and centrically well defined position of the two members relative to each other, said first driven member is equipped with a centrically as well as an eccentrically arranged driving pin, the outer surfaces thereof having at least partially a conical shape. The conical parts of the surfaces engage with openings correspondingly arranged in the driving plate, which is elastically deformed upon connection of the second member to the first member.
    Type: Grant
    Filed: October 18, 1983
    Date of Patent: October 7, 1986
    Assignee: Erowa AG
    Inventor: Rudolf Schneider
  • Patent number: 4488029
    Abstract: In electro-erosive machining apparatuses with multidimensional relative motion between a tool-electrode and a workpiece electrode, a simple and adaptable control is provided for these relative operating movements, with a superimposed shaping-limiting control and subordinated cyclic repetitive oblique erosion. In this connection, the tool-feed is limited, within individual oblique-erosion cycles, by achieving a predetermined shaping envelope-surface. The apparatus comprises two separate coordinating-function-transmitters by means of which two operating movements, at an angle to each other, are each determinable according to a resultant relative operating movement between the tool and the workpiece, one being used for shaping-limiting control and the other for oblique erosion. Initiation of the consecutive oblique-erosion cycles is effected by means of a repetition-circuit as a function of a rated-value/actual-value approximation of the shaping-limiting control.
    Type: Grant
    Filed: February 13, 1981
    Date of Patent: December 11, 1984
    Assignee: Erowa AG
    Inventors: Niklaus Liechti, Rudolf Schneider
  • Patent number: 4485288
    Abstract: In swinging wire guides for generally conical finishing surfaces, the problem exists of a reliable automatic coaxial setting of the guide axes according to the particular angular position of the wire electrode in the workpiece finishing zone.As a solution, the wire guides (DF1, DF2) supported swinging on the support elements (TO1, TO2) are joined together by a coupling device, which has a guide member (FG) joined correspondingly with the support elements. The latter is set by the relative movement of the wire guides (DF1, DF2) to the desired angular position of the wire guides according to the ideal wire guide axis (D--D). Through swinging coupling gears (SK1, SK2) the angle position of the guide member (FG) is transmitted to the wire guides (DF1, DF2).
    Type: Grant
    Filed: November 1, 1982
    Date of Patent: November 27, 1984
    Assignee: Erowa AG
    Inventor: Rudolf Schneider
  • Patent number: 4347422
    Abstract: The speed at which the electrode on a spark erosion machine approaches the workpiece is controlled in accordance with the continuously measured force on the electrode due to the pressure of the dielectric. This force may be measured by a pre-stressed spring in the traction rod of the electrode carrier or by extension strain measuring strips on said traction rod. Apparatus to which the process is particularly suitable is described.
    Type: Grant
    Filed: March 15, 1979
    Date of Patent: August 31, 1982
    Assignee: Erowa AG
    Inventor: Rudolf Schneider
  • Patent number: 4203018
    Abstract: A method and apparatus for eroding inner and outer walls of work pieces, such as cylinders and cones, by electrical discharge between the work piece and an electrode are described wherein an electrode-holder is mounted for variable orbital movement on a hollow support fixed on a cylinder axially movable by fluid pressure with respect to a piston therein, along an axis perpendicular to the plane of the orbital movement. A normally fixed piston rod carries the piston, and a shaft extends through the piston rod from the interior of the support to means, providing for coarse and fine adjustment, fixing the shaft to the rod. A rotor in the support is rotatable on the shaft and has an inclined track with which an inclined track on a cam unit is in sliding engagement.
    Type: Grant
    Filed: December 13, 1977
    Date of Patent: May 13, 1980
    Assignee: Erowa AG
    Inventor: Rudolf Schneider