Work Or Work Carrier Slides On Heated Chamber Wall Or Floor Patents (Class 432/153)
  • Patent number: 6926522
    Abstract: An apparatus for preheating particulate material in which the particulate material is transferred from one or more upper storage bins to a circular lower chamber that has an outer, essentially annular, portion which serves as a gas flow passage. The particulate material is directed from the feed bin or bins into a plurality of essentially vertical cylindrical feed cassettes via intermediate feed ducts. The lower chamber has a flat roof which is in contact with the bottom portion of the vertical feed cassettes. The vertical feed cassettes are approximately evenly spaced on top of the outer perimeter of the flat roof. The particulate material is preheated in the annular flow passage by hot kiln gases flowing in countercurrent heat exchange relationship with the particulate material.
    Type: Grant
    Filed: September 30, 2003
    Date of Patent: August 9, 2005
    Assignee: FFE Minerals USA Inc.
    Inventors: John P. Townsend, Charles R. Euston, Douglas P. Freeman, Michael E. Prokesch
  • Patent number: 6644962
    Abstract: A method of controlling a furnace pressure for preventing air from intruding to a heating furnace, a method of stable operation during low combustion load of heat regenerating burners and a method of measuring concentration of an atmospheric gas in a heating furnace are proposed.
    Type: Grant
    Filed: September 4, 2002
    Date of Patent: November 11, 2003
    Assignee: Kawasaki Steel Corporation
    Inventors: Ichiro Sugimoto, Kenta Karube, Masahiro Furukawa, Kazunari Andachi
  • Patent number: 6270305
    Abstract: A high-temperature conveyor furnace with a low friction conveyor travel surface is provided. The furnace includes a muffle defining a heating chamber, hearth plates providing a hearth surface within the heating chamber, and a conveyor belt to convey product through the heating chamber. The conveyor belt is formed of a first material, such as a nickel-chrome alloy. A plurality of low-friction inserts are supported by the hearth plates, preferably in openings in the hearth plates, to provide a surface upraised from the hearth surface upon which the conveyor belt travels. The inserts are formed of a second material, such as an electronics grade ceramic, that is different from the first material of the conveyor, which minimizes friction between the inserts and the belt. The low-friction surface is particularly suitable for high temperature, low dewpoint furnace applications, such as stainless steel brazing.
    Type: Grant
    Filed: June 12, 2000
    Date of Patent: August 7, 2001
    Assignee: BTU International, Inc.
    Inventors: Gary Orbeck, Robert Hutcheson
  • Patent number: 6230956
    Abstract: A conveyor support for integrated circuits in an on-line oven, including a mechanism for driving and guiding the elements to be soldered while maintaining a lower surface of one of said elements in direct contact with a wall of the oven.
    Type: Grant
    Filed: July 29, 1999
    Date of Patent: May 15, 2001
    Assignee: STMicroelectronics S.A.
    Inventors: Jean-Paul Farroni, Christian Gehin
  • Patent number: 5848890
    Abstract: This invention involves a transport system for moving work products through a furnace or kiln. The structure is simple in construction and moves easily along two grooves or channels provided at both sides of the product supporting structure. The supporting structure is a plurality of cross bars resting on a carrier or carriers on each side thereof. The structure resists warping and rapid deterioration generally occuring in prior art structures. It importantly allows uniform heating of the product because of the open atmosphere provided therein.
    Type: Grant
    Filed: December 13, 1996
    Date of Patent: December 15, 1998
    Inventor: Edward V. McCormick
  • Patent number: 5722825
    Abstract: A device for heat-treating metallic workpieces in a vacuum has a revolving vacuum furnace with an inlet transfer lock for introducing a batch of workpieces into the revolving vacuum furnace and with an outlet transfer lock for removing the batch of workpieces from the revolving vacuum furnace. The revolving vacuum furnace has also an annular turntable for transporting the batch of workpieces from the inlet transfer lock to the outlet transfer lock. At least one carburization furnace, for carburization treatment of the batch of workpieces, is connected to the revolving vacuum furnace at least at a peripheral location of the revolving vacuum furnace between the inlet transfer lock and the outlet transfer lock in the direction of transportation of the batch of workpieces. The annular turntable transports the batch of workpieces to the at least one carburization furnace.
    Type: Grant
    Filed: March 29, 1996
    Date of Patent: March 3, 1998
    Assignee: Ipsen Industries International GmbH
    Inventor: Bernd Edenhofer
  • Patent number: 5697777
    Abstract: A curing device for drying bonding material used for bonding, for example, chips to a lead frame for semiconductor devices including a workpiece heating chamber casing having heating blocks for heat-drying the bonding material and a gas supply chamber casing provided above the workpiece heating chamber casing so as to cover the heating chamber casing and to supply a high-temperature gas to the surfaces of the heating blocks, and the gas supply chamber casing is constructed so that it can be opened and closed with respect to the workpiece heating chamber casing, assuring easy access to the inside of the heating chamber casing for various works such as cleaning of the heating blocks, etc.
    Type: Grant
    Filed: September 1, 1995
    Date of Patent: December 16, 1997
    Assignee: Kabushiki Kaisha Shinkawa
    Inventors: Mitsuo Arai, Toshiharu Suganuma
  • Patent number: 5619934
    Abstract: A waste car disposer which includes a plurality of tunnel-like furnaces connected in series and separately controlled to heat waste cars at different temperatures so that plastic, rubber, glass, lead, zinc, nickel, copper, iron and steel parts of waste cars are separately melted and respectively collected for reclamation.
    Type: Grant
    Filed: February 8, 1996
    Date of Patent: April 15, 1997
    Inventor: Chin-Ching Yen
  • Patent number: 5489204
    Abstract: An apparatus useful for sintering unsintered abrasive grain precursor to provide sintered abrasive grain. The sintered abrasive grain can be incorporated into abrasive articles such as bonded abrasives (e.g., grinding wheels), coated abrasives, and nonwoven abrasives.
    Type: Grant
    Filed: December 28, 1993
    Date of Patent: February 6, 1996
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Stanley L. Conwell, William P. Wood
  • Patent number: 5478442
    Abstract: A rotary hearth calciner for treating petroleum cokes with a puffing inhibitor has a horizontal or inwardly sloping hearth floor rotatable around a vertical axis for receiving particles of coke to be calcined and a central opening in the hearth floor for discharging the coke into a soaking pit. A water cooled, refractory covered feed pipe extending downward into the calciner interior has an inlet for connection to a source of petroleum coke puffing inhibitor and an outlet near the edge of the hearth central floor opening for adding the puffing inhibitor to the coke as the coke is discharged from said hearth floor. The feed pipe outlet is approximately at or below the level of the hearth floor to reduce loss of inhibitor in gas flow above the hearth floor. A puffing inhibitor such as sodium carbonate is supplied by a screw feed mechanism to the feed pipe to add the puffing inhibitor at a desired rate for reaction with the coke. The coke is normally maintained in the soaking pit for about 30 minutes at 1200.
    Type: Grant
    Filed: February 15, 1995
    Date of Patent: December 26, 1995
    Assignee: UCAR Carbon Technology Corporation
    Inventor: Thomas H. Orac
  • Patent number: 5446263
    Abstract: Device for setting the temperature of a sample selectively to different ves comprising a sample holder block having good thermal conductivity properties and at least one recess (14) for receiving a sample whose temperature is to be adjusted, and a device for adjusting the temperature of a sample holder block, wherein the device for adjusting the temperature of the sample holder block (12) comprises at least two bodies (18, 20) whose temperatures can be controlled via separate thermostats and whose temperatures can be adjusted to different values and wherein a transporter (30, 32, 34) is provided by a way in which the sample holder block (12) can be brought into thermal contact with one of the bodies (18, 20).
    Type: Grant
    Filed: May 3, 1991
    Date of Patent: August 29, 1995
    Assignee: Max-Planck-Gesellschaft zur Forderung der Wissenschaften e.V.
    Inventors: Manfred Eigen, Hajo Otten
  • Patent number: 5350295
    Abstract: A method for producing a plurality of kinds of heat-treated products economically and efficiently and with minimum sorting errors, using fewer number of heating devices than pre-treatment and post-treatment devices. Pre-treatment devices (e.g., compacting machines) and post-treatment devices (e.g., sizing presses and finishing devices) are provided upstream and downstream of the sintering furnace. Also provided is a carrier device comprising a carrier conveyor, a return conveyor and loading/unloading devices. A first transfer device and a second transfer device are provided between the entrance of the furnace and the conveyor and between the outlet of the furnace and the conveyor, respectively. Each heat-resistant tray carrying products (works) and supported on a corresponding carrier case is removed from the case and fed into the sintering furnace. The empty cases are put back on the conveyor and transported separately from the trays.
    Type: Grant
    Filed: January 26, 1993
    Date of Patent: September 27, 1994
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventor: Takeuchi Kenji
  • Patent number: 5340399
    Abstract: In an apparatus for the heat treatment of ophthalmic lenses, especially contact lenses, which comprises an approximately cylindrical housing of closed design having an inlet opening and an outlet opening, transport device for transporting the ophthalmic lenses located inside molds along an open transport path, which is arranged inside the housing and connects the inlet and the outlet opening, and heating device arranged inside the housing, the open transport path inside the housing is of an essentially spiral shape, and the heating device are arranged essentially above and below the transport path.
    Type: Grant
    Filed: March 17, 1993
    Date of Patent: August 23, 1994
    Assignee: Ciba-Geigy Corporation
    Inventors: Winfried Uftring, Theo Bachmann, Helmut Geis, Lothar Haase
  • Patent number: 5207578
    Abstract: A heat processing apparatus of the vertical type includes a box which has a process tube in the upper half thereof and a space in the lower half thereof. A cap for the process tube can be moved up and down between an upper position where the cap closes the process tube while holding a wafer boat on it and a lower position in the space where it opens the process tube. Clean air is supplied into the space through a dust removing filter located on one side of the space and exhausted from the space through the other side of the space. The air thus exhausted is collected by a gas processing system, which serves to remove harmful components from the air thus collected. A scavenger is arranged enclosing the open bottom of the process tube. Gas remaining in the process tube after the heat process is sucked by the scavenger and collected by another gas processing system.
    Type: Grant
    Filed: February 6, 1992
    Date of Patent: May 4, 1993
    Assignee: Toyko Electron Sagami Limited
    Inventor: Kazunari Sakata
  • Patent number: 5044944
    Abstract: A furnace of decreasing oxygen concentration to ultra low amount is basically characterized by providing a furnace body divided into a plurality of zones, a device for supplying a non-oxidizing or a reducing atmospheric gas into each of the zones so as to increase the internal pressure, shutter devices provided at least at an inlet and an outlet of the furnace body for checking the flowing atmosphere, transferring devices installed at the inside of the furnace, at the interior and at the outside thereof respectively, and a control device for opening the shutter device before the work in a transferring direction, wherein the transferring device installed within the furnace supports the work at its both sides of the under surface and continuously send it while the upper surface of the work is exposed to the atmosphere in the furnace.
    Type: Grant
    Filed: March 8, 1990
    Date of Patent: September 3, 1991
    Assignees: Yugen Kaisha R.I. Electronic Industry, Yamato Works Co., Ltd.
    Inventors: Toshio Furuya, Masayoshi Hamano
  • Patent number: 4981436
    Abstract: A vertical type heat-treatment apparatus of the invention has an adjusting mechanism capable of setting the flow rate of clean air flowing out from a first clean room to a second clean room to be a predetermined value. With this arrangement, the apparatus can be reduced in size and can prevent impurities from adhering to objects to be treated, thereby improving the productivity.
    Type: Grant
    Filed: June 23, 1989
    Date of Patent: January 1, 1991
    Assignee: Tel Sagami Limited
    Inventor: Shingo Watanabe
  • Patent number: 4900247
    Abstract: In a high-temperature heating furnace, its central longitudinal passage in which articles to be heated are placed, and its inner support which makes a space between its inner surface and the above-mentioned passage for accommodating heaters therein and which makes also another space between its outer surface and a furnace shell for filling insulators therein, are both installed in the furnace by assembling a plurality of thin plates made of carbon fiber reinforced graphite or carbon compounds to cuboids which are coaxial to each other and have rectangular cross sections.
    Type: Grant
    Filed: April 27, 1989
    Date of Patent: February 13, 1990
    Assignee: Kanto Yakin Kogyo K.K.
    Inventor: Susumu Takahashi
  • Patent number: 4795341
    Abstract: Method for sintering blanks into fuel pellets, in which the blanks are moved through the muffle of a tunnel furnace by pushing the blanks through the muffle on a guiding device which goes through the muffle and protrudes therefrom at least on the input side, in the form of a single-layer column of abutting blanks.
    Type: Grant
    Filed: January 15, 1987
    Date of Patent: January 3, 1989
    Assignee: Kraftwerk Union Aktiengesellschaft
    Inventors: Helmut Assmann, Wolfgang Dorr, Georg Maier, Martin Peehs
  • Patent number: 4764109
    Abstract: An oven for heat treating, curing, stress relieving or otherwise treating objects within the oven has side walls that can be moved into contact and out of contact with side edges of a movable floor. All interior surfaces of the oven are insulated and, when the floor is located in the oven, the side walls can be moved so that the insulation on the side walls forms a sealed relationship with the insulation along the adjacent side edges of the floor. A door of the oven can then be closed. When the door is opened, the side walls can be moved out of contact with the floor and the floor can be removed. Preferably, the side walls are moved by the operation of pneumatic cylinders.
    Type: Grant
    Filed: June 22, 1987
    Date of Patent: August 16, 1988
    Assignee: Clemmer Industries (1964) Limited
    Inventor: Arnold G. Meyers
  • Patent number: 4669977
    Abstract: Apparatus for drying and heating wet particulate materials comprises a furnace with stationary circular hearth and sidewalls and a rotating roof. The hearth is perforated to receive hot gases from a plenum chamber below it, which gases are drawn off from the hearth through conduit openings out of its sidewalls, the major portion of the gases are externally heated, and are returned to the hearth through the plenum chamber. A feed bin is positioned on the roof at its center and through a conveyor feeds charged material onto the hearth through an opening in the roof near its outside edge. Rabbles are mounted in the roof to move the charge toward the center of the hearth as the roof rotates. From the center of the hearth a soaking pit extending through the plenum chamber discharges the heated material.
    Type: Grant
    Filed: March 25, 1986
    Date of Patent: June 2, 1987
    Assignee: Salem Furnace Co.
    Inventors: Beverly E. Johnson, William E. Solano
  • Patent number: 4591336
    Abstract: Wires having an adherent coating of resin are passed through individual, segregated chambers in a convection oven where the resin is cured; if a wire fails to feed, heat to the chamber for that wire is discontinued and its chamber is cooled by a draft of forced air while the remaining wire-treating chambers continue in operation.
    Type: Grant
    Filed: April 19, 1984
    Date of Patent: May 27, 1986
    Assignee: Moco Thermal Industries
    Inventor: Ronald L. Konczalski
  • Patent number: 4568279
    Abstract: This invention relates to a muffle furnace, for continuous heat treatment during passage of material therethrough, of products, the production cycle of which includes a treatment of predetermined duration at a temperature which may be about to about C., which furnace is heated by a flame producing burner without the combustion gases directly contacting the products to be treated. This furnace comprises: an inlet zone provided with a means for preheating, by circulating recycled combustion gases in a double casing provided around the muffle; a heating zone, provided inside a heat-insulated chamber provided with at least one means for circulating combustion gases around the heating zone of the muffle; and an outlet zone provided with at least one means for controlling the cooling rate of the treated product.
    Type: Grant
    Filed: March 5, 1985
    Date of Patent: February 4, 1986
    Assignee: Societe des Electrodes et Refractaires Savoie
    Inventors: Michel Logue, Maurice Sadzot
  • Patent number: 4540364
    Abstract: The material to be processed through a furnace is carried on skid rails by sliding shoes. In order to reduce the friction between the skid rails and the sliding shoes, and the breakaway forces at the start of the pushing motion, slip plates are fitted in shallow recesses in the top of the skid rails.
    Type: Grant
    Filed: September 23, 1983
    Date of Patent: September 10, 1985
    Inventor: Peter Ebner
  • Patent number: 4416623
    Abstract: Muffle furnace having an elongated metallic muffle extending through several heating zones of the furnace. Temperature of muffle is measured at different parts thereof. In order to minimize the difference of temperature which causes the deformation of muffle, heaters of furnace are controlled coincidentally so as to compensate said difference.
    Type: Grant
    Filed: February 1, 1982
    Date of Patent: November 22, 1983
    Assignee: Kanto Yakin Kogyo Kabushiki Kaisha
    Inventor: Susumu Takahashi
  • Patent number: 4400155
    Abstract: Equipment for heating pulverulent products, including a relatively flat, vertically standing vessel for receiving the product, and a rotatable agitator whose axis of rotation is coincident with the longitudinal axis of the vessel. There are heating facilities in the bottom of the vessel. With these heating facilities, the bottom and side wall of the vessel are heated. The top of the vessel is insulated. The product is introduced into the vessel through the top and discharged in the region of the bottom of the vessel.
    Type: Grant
    Filed: November 2, 1981
    Date of Patent: August 23, 1983
    Assignee: Linhoff & Thesenfitz Maschinenbau GmbH
    Inventor: Klaus Thesenfitz
  • Patent number: 4383378
    Abstract: A secondary dryer device comprising a drying oven, for subjecting open containers of water detector pads to a secondary drying operation. The oven has a pair of elongate channels disposed side by side with open, outer-most ends and blind inner-most ends. One channel holds a plurality of containers in single file, whereas the other channel holds a plurality of containers in double file, whereby the dwell time is greatly increased. A transfer structure interconnects the blind ends of the channels to provide transfer of the containers from the narrow channel to the wider channel. A powered pushing device applies force to the containers of the single file, to advance said containers inwardly into the oven, toward the blind end of the channel. The oven has means which provides heat to raise the temperature and expel moisture.
    Type: Grant
    Filed: March 2, 1981
    Date of Patent: May 17, 1983
    Inventor: Harry A. Lockwood
  • Patent number: 4255129
    Abstract: A method for processing various organic materials such as lignocellulosics or biomass into more useful states, such as charcoal, carbon black, and coke, and other processed products while producing useful off-gases, includes feeding aggregate pieces of the material to a vertically extending heating chamber and, preferably, closing the chamber to air to control oxygen therein. The pieces are conveyed upwardly through the chamber in a predetermined time by spiral vibratory conveyor. The chamber is heated to a preselected temperature sufficient for gaseous conversion of volatile hydrocarbon constituents of the material. Resultant off-gases are removed from the chamber for further use such as burning thereof for heating the chamber or condensing volatiles, etc.Apparatus for carrying out the method includes preferably first and second such chambers, there being continuous spiral vibrator tray in each chamber carried by a central, vertical support column.
    Type: Grant
    Filed: July 11, 1979
    Date of Patent: March 10, 1981
    Assignee: Thomas N. DePew
    Inventors: Roger D. Reed, Elmer E. Reed
  • Patent number: 4136624
    Abstract: An incinerator is provided with water cooled nozzles for blowing pressure air into refuse in open-topped containers, fuel burners for heating the containers from the outside, a water cooled grate and doors at the inlet and outlet of the incinerator. The containers are mounted on receiver dishes, delivered in sequence into the incinerator. Refuse is incinerated by blowing pressure air from the nozzles down into each container while heating the container at its sides. Emptied containers can be reused.
    Type: Grant
    Filed: July 7, 1977
    Date of Patent: January 30, 1979
    Assignees: Sumitomo Durez Co., Ltd, Kabushiki Kaisha Niihama Tekkojo
    Inventors: Nobuhide Kato, Ryo Yasuno, Susumu Yajima
  • Patent number: 4125365
    Abstract: An apparatus for heating billets and the like prior to hot extrusion is disclosed. The apparatus includes an elongated, insulated tunnel having an inlet opening and an outlet opening. A conveyor extends through the tunnel from the inlet to the outlet and conveys a plurality of equally spaced, transversely arranged billets in a step-like manner. The conveyor rotates the billets as they are conveyed through the tunnel. A source of high temperature air is connected to a plenum positioned above the conveyor. High temperature air is discharged from the plenum through a plurality of slot-like jets positioned above the billets so that the air directly impinges on the billets. Temperature probes are included for insuring that the billets are biased to one side of the conveyor upon discharge and for sensing the billet temperature to control the air temperature within the tunnel. An unloader is provided for receiving the billets discharged from the tunnel and rotating them through an angle of
    Type: Grant
    Filed: April 7, 1977
    Date of Patent: November 14, 1978
    Assignee: Oliver Machinery Company
    Inventor: John W. Nelson
  • Patent number: 4106893
    Abstract: A sintering furnace for sintering magnetic-ceramic articles is in the form of a quick-firing carriage furnace having a cooling system for indirect cooling in a cooling zone, having a sluice chamber at its outlet-end and being gastight at its base.
    Type: Grant
    Filed: February 24, 1977
    Date of Patent: August 15, 1978
    Assignee: Ludwig Riedhammer GmbH & Co. K.G.
    Inventors: Helmut Baumann, Fritz Petzi
  • Patent number: 4069010
    Abstract: A kiln of relatively simple design and low-cost construction is provided for firing ceramic ware. The kiln is of the shuttle type consisting generally of a rectangular enclosing structure with a movable floor which may consist of cars for supporting the ware. Burners are located along the lower part of each side wall and provided with air in excess of that required for combustion to produce high velocity streams of hot gas flowing vertically upward along the inside of the walls. The hot gas is redirected downward to flow through the ware and exhausted below the ware into horizontal flues on each side of the kiln from which gas is aspirated into the high velocity vertical gas streams for recirculation.
    Type: Grant
    Filed: June 16, 1976
    Date of Patent: January 17, 1978
    Assignee: Hendryx Engineers Incorporated
    Inventor: Gordon C. Fay
  • Patent number: 4039278
    Abstract: A tunnel oven for bakery purposes has a plurality of horizontally- and vertically-spaced hot air supply orifices in each of its vertical walls. At least some and preferably all such orifices are individually adjustable slots. Each wall also has air extraction orifices connected to suitable ducting.
    Type: Grant
    Filed: March 13, 1975
    Date of Patent: August 2, 1977
    Inventor: Andrew Denholm
  • Patent number: 4033715
    Abstract: A heat processing system in which a product is efficiently conveyed through a high temperature furnace and in which the product can be stored within a section of the furnace at a temperature less than the critical temperature to which product exposure must be limited. The furnace includes multiple sections each of a respective operating temperature, one of the sections being of high temperature to which a product can be exposed for only a limited time. A supply of product carriers is contained within the furnace onto which a product is supplied for transport forwardly through the furnace for unloading at an opposite end thereof, the carriers being returned rearwardly through the furnace back to a loading area. During an emergency mode of operation, loading of the product is discontinued and the product already within the furnace is transferred from the critical heat section to an adjacent section for storage at a lower temperature less than the high critical temperature.
    Type: Grant
    Filed: January 12, 1976
    Date of Patent: July 5, 1977
    Assignee: BTU Engineering Corporation
    Inventor: Jacob Howard Beck
  • Patent number: 4022570
    Abstract: A heat transfer apparatus for controlling the temperature of a formed workpiece is provided. The apparatus is in the form of a multi-tier rotary preheat, quench and heat recovery tunnel which provides for transfer of heat between tiers from workpieces to be cooled to workpieces to be heated, thereby conserving heat energy. Transfer of heat is accomplished by means of fans interconnected with the tier levels of the tunnel. A control system ensures proper temperature of air, passing through a hot-air fan, which is removed from a second level and transferred to a first level. Means are provided for loading slugs to be preheated prior to forming onto a first annular tray on the first level and for removing same after it has completed a single rotation about the cooling tunnel. After being further heated in an induction furnace, the slug is warm formed in a press to a desired configuration.
    Type: Grant
    Filed: May 5, 1976
    Date of Patent: May 10, 1977
    Assignee: Caterpillar Tractor Co.
    Inventors: James W. Ross, Jr., Francis H. Bricmont
  • Patent number: 3994678
    Abstract: An apparatus for heating materials such as aluminum billets to a temperature suitable for extrusion is disclosed. The apparatus has at least two zones arranged in tandem, a preheat zone and one or more primary heating zones. Every zone has inner and outer chambers. The outer chamber is supplied with high temperature gas at a pressure in excess of that of the inner chamber. The chambers are separated by baffles which define narrow slot-like aspirating throats through which secondary gases from a secondary source are jetted after entraining high temperature gases from the primary chamber. The secondary gases are at a lower temperature to provide efficient impingement of the gases on a target such as a billet with the primary gases providing the principle heat source. The apparatus is of the closed type utilizing rapid recycling of gases for efficient use of thermal energy.
    Type: Grant
    Filed: May 12, 1975
    Date of Patent: November 30, 1976
    Assignee: Oliver Machinery Company
    Inventor: John W. Nelson