Patents by Inventor Erwin Buhrer

Erwin Buhrer has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 4278125
    Abstract: A system for handling pattern devices in molding apparatus for producing mold halves in mold boxes includes a rotatable transfer device having a pair of diametrically opposed tables whereby rotation of the transfer device will periodically shift the tables between a waiting position and an operating position located on opposite sides of the axis of rotation of the transfer device. A conveyor track system is provided having a portion thereof defined by conveyor track elements located on the tables. The conveyor track system includes an upper track section and a lower track section and the overall conveyor track system is formed to define a closed circulation path for the pattern devices.
    Type: Grant
    Filed: November 14, 1979
    Date of Patent: July 14, 1981
    Assignee: Georg Fischer Aktiengesellschaft
    Inventor: Erwin Buhrer
  • Patent number: 4241778
    Abstract: Sand bales containing castings are removed from poured foundry molds by clamping together in a horizontal position the molding boxes containing the sand bales, by supporting the sand bales from below independently of the molding boxes, and by applying to the molding boxes jarring or accelerative forces acting in a vertical direction with a magnitude exceeding the static frictional forces which exist between the sand bales and the molding boxes, with these forces being applied while the sand bales are supported thereby to cause the sand bales to move out of the molding boxes. In one aspect, the sand bales are supported from below by a force lower than the weight of the bales thereby to permit the bales to drop out of the molding boxes while the accelerative forces are applied to the molding boxes in an upward direction. Conversely, the sand bales may be lifted upwardly out of the molding boxes with accelerative forces being applied to the molding boxes in a downward direction.
    Type: Grant
    Filed: December 26, 1978
    Date of Patent: December 30, 1980
    Inventor: Erwin Buhrer
  • Patent number: 4203484
    Abstract: A foundry molding machine for producing mold halves in mold forming assemblies which include a pattern device and mold boxes and operates to separate the formed mold halves from the pattern device through operation of a generally vertically extending main cylinder which includes a piston rod having an extension thereon. The extension includes clamping levers which are arranged in pairs to hold the mold boxes in clamped engagement. At least one auxiliary cylinder is arranged in generally parallel relationship with the main cylinder and is located in a laterally spaced arrangement relative thereto for operation on the opposite side of the clamped mold box. The auxiliary cylinder is operatively associated with the main cylinder to be simultaneously supplied with pressure medium from a common source and acts on the extension to provide support during separation of the mold members from the pattern device.
    Type: Grant
    Filed: July 13, 1978
    Date of Patent: May 20, 1980
    Inventor: Erwin Buhrer
  • Patent number: 4199020
    Abstract: Mold forming apparatus including a pattern device which is composed of pattern plates adapted to be operatively fitted into a pattern plate carrier is operated with the pattern device shifted between a lifting station, at which a formed mold may be removed from the patterns of the pattern plates, and an exchange station where the pattern plates may be separated from the pattern plate carrier for appropriate treatment thereof. The pattern plate carrier is formed in a generally box-like configuration with a bottom member having openings extending therethrough through which extraction pins of a lifting device may extend in order to raise and lower the pattern plates from the pattern plate carrier at the exchange station. A vacuum system is provided which will tend to hold the pattern plate carrier upon a bearing member of the apparatus and which will also tend to hold the pattern plate upon the pattern plate carrier while the finished mold is removed therefrom.
    Type: Grant
    Filed: October 27, 1978
    Date of Patent: April 22, 1980
    Inventor: Erwin Buhrer
  • Patent number: 4167208
    Abstract: A system for producing foundry molds providing a device for filling empty mold boxes with mold forming material at a filling station includes a first rotary shifting device and a second rotary shifting device located on opposite sides of the filling station. The first shifting device operates to shift pattern devices from the filling station to a first shifting station while simultaneously moving another pattern device from the first shifting station into position at the filling station. Likewise, the second shifting device moves mold halves from the filling station to a second shifting station while simultaneously moving an empty mold box from the second shifting station to the filling station. The pattern devices are moved to and from the first shifting station by a first conveyor device and the empty mold boxes and the mold halves are moved to and from the second shifting station by a second conveyor device which extends generally parallel to the first conveyor device.
    Type: Grant
    Filed: June 12, 1978
    Date of Patent: September 11, 1979
    Inventor: Erwin Buhrer
  • Patent number: 4114678
    Abstract: In mold forming apparatus wherein molding sand contained in a mold flask is subjected to compressive forces, bracer devices acting in opposed relationship against the mold flasks are provided in order to supprt the sides of the flasks against the forces generated therein during compression of the molding sand. The bracer devices act against structural parts of the molding apparatus or machine which are located to be fixed in position relative to the mold flasks during the compression of the sand and the bracer devices are arranged to consist of bracer bolts which are adapted to be brought into engagement against the sides of the mold flasks by wedge devices sliding relative to the fixed structural parts and actuated preferably by fluid pressure means.
    Type: Grant
    Filed: February 2, 1977
    Date of Patent: September 19, 1978
    Inventor: Erwin Buhrer
  • Patent number: 4114675
    Abstract: The amount of liquid metal casting material poured into a mold from a receptacle located above the mold from pouring means in the bottom of the receptacle is controlled by continuously sensing the pressure head of the liquid metal casting material in the receptacle during pouring of the mold, numerically integrating to a constant value the product of the multiplication of a function of the pressure head and time, and controlling the pouring means to terminate the pouring of the mold when a predetermined set value is attained. Electronic control circuitry receives as an input signal a signal representing the pressure head of the liquid casting material within the receptacle and a control function is effected by the electronic control means to stop pouring when a selected predetermined amount of material has been introduced into a mold.
    Type: Grant
    Filed: March 11, 1977
    Date of Patent: September 19, 1978
    Inventor: Erwin Buhrer
  • Patent number: 4084709
    Abstract: In a production operation, such as a molding operation, a device is used for moving both the molded parts produced and molds or similar elements used in the operation, between different working stations. The device includes support frames releasably engageable with the molded parts or elements to be moved and a mechanism supporting the frames. The mechanism extends vertically and can be lifted, lowered and rotated about its vertical axis. The movement of the mechanism is regulated so that the parts or elements being moved can be located in exact position at the working stations without any damage to the mechanism used in the moving operation or to the elements or items being moved.
    Type: Grant
    Filed: September 20, 1976
    Date of Patent: April 18, 1978
    Inventor: Erwin Buhrer
  • Patent number: 4077459
    Abstract: In the production of a foundry mold utilizing mold forming apparatus which includes a pattern device, a molding box arranged on the pattern device and a frame attached to the molding box, a surplus amount of molding sand is initially filled in over the pattern device in excess of the amount required for the production of the mold and during the production operation the excess sand is stripped off by profiled stripping means which are moved relative to the molding box to strip the excess sand along a profile which is dependent upon the configuration of the pattern device. In one aspect of the invention a single profiled stripper may be used and in another aspect a plurality of strippers having differring profiles may be employed. In other aspects of the invention different mechanisms are applied to move the stripping means relative to the molding sand by movement of the pattern device either along a linear path or through a circular path.
    Type: Grant
    Filed: December 9, 1975
    Date of Patent: March 7, 1978
    Inventor: Erwin Buhrer
  • Patent number: 4077461
    Abstract: Apparatus for the production of foundry molds within a mold forming assembly which at least includes a pattern device and a molding box capable of having molding material contained therein is adapted to effect simultaneous free-fall jolting and squeezing of the molds during their production within a molding machine having a press and a jolter table with at least a pair of columns rigidly connecting said press with said jolter table to form a gantry. Conveyor means are provided for reversibly moving the mold forming assembly from a position at which the molding box is put onto the pattern device and filled with molding material to another position within the gantry where the simultaneous free-fall jolting and squeezing is effected. Coupling means are provided for coupling and uncoupling the pattern device with the conveyor means to effect movement of the mold forming assembly to both of the aforementioned operating positions.
    Type: Grant
    Filed: December 4, 1975
    Date of Patent: March 7, 1978
    Inventor: Erwin Buhrer
  • Patent number: 3997088
    Abstract: For pouring molten metal, a device is provided which affords a flow passage between a source of supply of the molten metal and a mold. The device is supported separately from the mold and can be rotated about a vertical axis and tilted about a horizontal axis. A jet deflecting member is provided in the flow passage to provide a kinetic energy dissipating effect and the passage is arranged to afford automatic emptying of the molten metal from the device. Various embodiments of the flow passage include walls forming a tortuous flow path or a weir-shaped wall between the inlet and the outlet of the device. Additionally, a downwardly inclined elongated nozzle forms the flow passage outlet from the device with the outlet offset relative to the inlet to the device.
    Type: Grant
    Filed: December 4, 1974
    Date of Patent: December 14, 1976
    Inventor: Erwin Buhrer
  • Patent number: 3989086
    Abstract: A storage vessel filled with a granular composition for forming mold parts has a bottom opening aligned with an opening in a pressure vessel located directly below the storage vessel. Upon being filled with the granular composition from the storage vessel, the pressure vessel is arranged so that the opening can be closed. The pressure vessel is movable vertically toward and away from the storage vessel. In its upper position it can be filled with the composition, and in its lower position can evacuate the granular composition into a cavity in a core molding device through nozzles situated at the bottom of the pressure vessel. The nozzles are directed into bores in the molding device and allow the granular material to exit when a compressed air source within the pressure vessel is activated.
    Type: Grant
    Filed: September 23, 1974
    Date of Patent: November 2, 1976
    Inventor: Erwin Buhrer
  • Patent number: 3974872
    Abstract: In a system for the production of molds for casting, a pair of pattern plates are disposed in an opposed facing relationship with a frame located therebetween in a manner whereby the opposing pattern surfaces of the plates, together with the frame, define an enclosed cavity within which a casting mold section may be formed. The frame is preferably provided with an opening through which the cavity may be filled with molding material which, after hardening, forms a mold section. After separation of the pattern plates and frame, the mold section is conveyed into assembled relationship with one or more other mold sections in order to form a mold for casting. Pattern plates and frames may be arranged in a mass production facility to continuously form mold sections which, when assembled, will provide a mold stack for producing multiple castings.
    Type: Grant
    Filed: December 17, 1973
    Date of Patent: August 17, 1976
    Inventor: Erwin Buhrer
  • Patent number: 3970138
    Abstract: The upper part of a foundry mold is manufactured by utilizing a pattern device which includes a gate pin having a guide hole therein which is adapted to engage a guide pin extending from the mold pattern of the foundry mold in order to retain the pattern device in place during production of the upper part of the foundry mold. An upper trough pattern may be mounted for axial movement relative to the gate pin. The upper trough pattern is configured to define a trough from which a plurality of gate pins may extend. By structuring at least two of the gate pins located at opposite ends of the trough with guide holes engaging guide pins extending from the mold pattern, rotation of the upper trough pattern about either of the guide pins may be prevented.
    Type: Grant
    Filed: August 29, 1974
    Date of Patent: July 20, 1976
    Inventor: Erwin Buhrer
  • Patent number: 3968830
    Abstract: Foundry molds may be compressed and vibrated between a vibration table and a presser plate within apparatus which is structured to enable connection of the vibration table and the presser plate as a rigid frame during the compression and vibration process. The coupling means forming the rigid frame include locking means which may be actuated between a locked and an unlocked position whereby a gap may be formed when the coupling means are in the unlocked position to enable foundry molds to be swung in place by horizontally extending arms to effect location of the foundry molds between the vibration table and the presser plate. Damper means are also provided which damp and limit the movement of the presser plate and its associated pressure applying means in both an upward and a downward direction.
    Type: Grant
    Filed: November 26, 1974
    Date of Patent: July 13, 1976
    Inventor: Erwin Buhrer