Patents by Inventor Thomas R. Campbell

Thomas R. Campbell 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: 9109333
    Abstract: A hopper insert for the hopper of a paving machine is installed above a hopper conveyor that conveys asphalt material in a hopper conveying direction. The hopper insert has a front end and a rear end and a plurality of walls that together define an opening adjacent to the hopper conveyor. The opening to the hopper conveyor increases in width from front end of the hopper insert to the rear end.
    Type: Grant
    Filed: June 18, 2012
    Date of Patent: August 18, 2015
    Assignee: Roadtec, Inc.
    Inventors: Thomas R. Campbell, David Swearingen
  • Publication number: 20130010565
    Abstract: A hopper insert for the hopper of a paving machine is installed above a hopper conveyor that conveys asphalt material in a hopper conveying direction. The hopper insert has a front end and a rear end and a plurality of walls that together define an opening adjacent to the hopper conveyor. The opening to the hopper conveyor increases in width from front end of the hopper insert to the rear end.
    Type: Application
    Filed: June 18, 2012
    Publication date: January 10, 2013
    Applicant: Roadtec, Inc.
    Inventors: Thomas R. Campbell, David Swearingen
  • Patent number: 6733086
    Abstract: A vacuum system is mounted on a portable milling machine for extracting material cut by the milling drum of the machine from the surface of a roadway. The milling machine includes a frame, a propulsion system for advancing the machine across a surface to be milled, a milling drum mounted on the frame for rotation about its axis, and a conveyor for conveying material cut by the milling drum away from the drum. The vacuum system includes a vacuum pump having an air inlet and an air outlet and a nozzle mounted behind the milling drum having an opening for receiving material cut from the surface by the drum. The vacuum system also includes a material collector having an inlet, an air outlet and a material outlet. The collector is adapted for collecting material entrained in air by the pump through the collector inlet and for discharging such material through the material outlet onto the conveyor. The vacuum system also includes a first conduit and a second conduit.
    Type: Grant
    Filed: March 15, 2002
    Date of Patent: May 11, 2004
    Assignee: RI Properties, Inc.
    Inventors: Chris McSharry, Thomas R. Campbell
  • Patent number: 6466927
    Abstract: A procedure and method for eliciting expert information on process capability and thereafter manipulating the elicited information in such a manner that it can effectively be used in a process capability database that is operating in a six sigma regime. The manipulation preferably includes converting the expert elicited information from a tolerance-type metric to a short term standard deviation (or sigma) metric, whereby the result of the manipulation is used to populate directly a process capability database and, as appropriate, thereby augment, replace or modulate the data already stored therein.
    Type: Grant
    Filed: November 10, 1999
    Date of Patent: October 15, 2002
    Assignee: General Electric Company
    Inventors: John J. Dougherty, Thomas R. Campbell, Alan L. Arvidson
  • Patent number: 6232860
    Abstract: A latching system for a circuit breaker is arranged to actuate a trip unit and interrupt circuit current upon occurrence of a short circuit or an overcurrent condition. The latching system employs an armature having a recess formed therein and a cradle having a cradle tip arranged to releasably engage the recess. A thermal magnetic trip unit is depicted within the circuit breaker for the purposes of detecting overcurrent conditions through the electric path. During current transport through the circuit breaker, the current is thermally sensed by means of the bimetal and magnetically sensed by means of the magnet. The armature rotates against the return bias of a compression spring to release the cradle tip from the recess and allow counterclockwise rotation of the contact arm. The rotation of the contact arm causes the separation of the movable and fixed contacts under the urgence of a mechanism spring.
    Type: Grant
    Filed: June 23, 2000
    Date of Patent: May 15, 2001
    Assignee: General Electric Company
    Inventors: Pedro Acevedo, Javier I. Larranaga, Joseph Criniti, Thomas R. Campbell, Jose Velez
  • Patent number: 5851085
    Abstract: A paving machine employs in combination a gravity feed HMA hopper and a tack spray assembly and storage tank. Use of the gravity feed hopper permits all HMA or other paving material stored therein to be discharged directly on top of the paving machine's distributing auger. Moreover, because the gravity feed hopper takes up a relatively small percentage of the horizontal area of the paving machine, a chassis of standard or near standard dimensions can receive a tack storage tank of sufficient capacity to permit the paving machine to operate an entire day without stopping the machine to refill the storage tank. Therefore, if used in conjunction with an HMA shuttling apparatus, the paving machine can simultaneously coat a surface to be paved with a tack material and pave that surface with HMA for prolonged periods of time without stopping to refill either the HMA hopper of the tack storage tank.
    Type: Grant
    Filed: December 30, 1996
    Date of Patent: December 22, 1998
    Assignee: Astec Industries, Inc.
    Inventor: Thomas R. Campbell
  • Patent number: 5642961
    Abstract: A method for desegregating and conveying aggregate includes reorienting aggregate from a side-by-side lateral orientation to a longitudinal orientation. The longitudinally oriented segregated aggregate may then be thoroughly desegregated in a second conveyor. Reorientation preferably occurs as the aggregate is conveyed along a drag slat conveyor which has a notch in the floor of its discharge end which causes larger aggregate at the lateral edges of the conveyor to drop out of the conveyor after smaller aggregate located between the lateral edges.
    Type: Grant
    Filed: April 16, 1996
    Date of Patent: July 1, 1997
    Assignee: Astec Industries, Inc.
    Inventor: Thomas R. Campbell
  • Patent number: 5615973
    Abstract: A paving machine has a gravity feed hopper which is capable of delivering by gravity to the paving apparatus substantially all of the paving materials stored in the hopper without employing any internal conveyors. The discharge opening of the hopper is selectively closed by a feeder gate, the degree of opening of which is preferably coordinated with other operating parameters of the machine such as vehicle speed, distributing auger height and/or speed, and screed operation. Use of the gravity feed hopper significantly reduces construction and maintenance costs, provides a more uniform feed of materials from the hopper, and permits the use of a smaller engine. The paving machine as thus constructed is also relatively easy to operate and thus can be controlled by a single operator seated in the vicinity of the screed.
    Type: Grant
    Filed: September 29, 1994
    Date of Patent: April 1, 1997
    Assignee: Astec Industries, Inc.
    Inventor: Thomas R. Campbell
  • Patent number: 5553968
    Abstract: An apparatus and method for desegregating and conveying aggregate. A drag slat conveyor has a notch in the floor of its discharge end which causes larger aggregate at the lateral edges of the conveyor to drop out of the conveyor after smaller aggregate located between the lateral edges. The larger and smaller aggregate are thereby reoriented from a side-by-side lateral orientation to a longitudinal orientation. The longitudinally oriented segregated aggregate may then be thoroughly desegregated in a second conveyor.
    Type: Grant
    Filed: September 29, 1994
    Date of Patent: September 10, 1996
    Assignee: Astec Industries, Inc.
    Inventor: Thomas R. Campbell
  • Patent number: 5533828
    Abstract: A paving machine discharges HMA or other paving materials directly on top of a distributing auger located between the paving material storage hopper and the screed. The distributing auger is then capable of remixing any partially segregated paving materials and of uniformly distributing the paving materials directly adjacent a previously-paved segment. Materials may be discharged on top of the distributing auger from a discharge opening of a gravity feed hopper located adjacent the distributing auger or from an inclined conveyor delivering materials from a more standard hopper mounted near the front end of the paving machine.
    Type: Grant
    Filed: February 16, 1995
    Date of Patent: July 9, 1996
    Assignee: Astec Industries, Inc.
    Inventor: Thomas R. Campbell
  • Patent number: 5533829
    Abstract: A paving machine is described which includes: a gravity feed hopper located near a front end of a chassis; a distributing auger mounted on the chassis near the rear end thereof and extending transversely across the chassis; a remixing device including a variable-pitch screw auger with i) a first flight section and ii) a second flight section, the second flight section being located transversely between a lower discharge opening of the hopper and the first flight section, the pitch of the first flight section being lower than the pitch of the second flight section so that volumes bounded by flights of the second flight section are greater than volumes bounded by flights of the first flight section, so as to enable finer paving materials, located in a transverse central portion of the hopper to enter void spaces in volumes bounded by flights of the second flight section and combine with coarser paving material, thereby remixing segregated paving materials; and a discharge conveyor assembly extending longitudina
    Type: Grant
    Filed: May 2, 1995
    Date of Patent: July 9, 1996
    Assignee: Astec Industries, Inc.
    Inventor: Thomas R. Campbell
  • Patent number: 5441361
    Abstract: A roadworking machine can be converted from front load road planing capability to cold in-place recycling capability by replacing the secondary conveyor on the front end of the machine with a mixer such as a standard pugmill. The machine can be converted in the field simply by detaching the conveyor from a-mounting assembly on the chassis and by attaching the pugmill to the same mounting assembly. The conveyor and pugmill are preferably attachable to the mounting assembly so as to be pivotable with respect to the chassis about both vertical and horizontal axes. The machine as thus constructed permits considerable versatility in both the discharge of milled materials from the secondary conveyor during front load planing and the discharge of recycled materials from the mixer during cold in-place recycling.
    Type: Grant
    Filed: December 17, 1993
    Date of Patent: August 15, 1995
    Assignee: Astec Industries, Inc.
    Inventor: Thomas R. Campbell
  • Patent number: 5405214
    Abstract: A paving machine employs at least one gate mechanism which can selectively alter the weighting of the flow of paving materials from the discharge opening of a hopper by adjusting the contour of the effective lower edge of the gate mechanism. This contour is preferably adjusted by forming the gate mechanism from front and rear vertically adjustable gates, the lower edges of which have opposed tapers. The discharge of materials from the opening is weighted towards one side when the front gate is raised and the rear gate lowered or partially lowered, and is weighted towards the other side when the rear gate is raised and the front gate lowered or partially lowered. Discharge may be prevented altogether by fully lowering both gates.
    Type: Grant
    Filed: August 12, 1993
    Date of Patent: April 11, 1995
    Assignee: Astec Industries, Inc.
    Inventor: Thomas R. Campbell
  • Patent number: 5348418
    Abstract: An asphalt finishing screed is disclosed which is adapted to achieve essentially complete compaction of the asphalt mix over a range of finished mat thicknesses. The screed comprises a vertically adjustable strike off bar, a rotary compactor positioned immediately behind the bar, and a screed plate positioned immediately behind the rotary compactor. In one preferred embodiment, the rotary compactor comprises a rotor which includes a plurality of freely rotating rollers about the peripheral surface thereof. In operation, the adjustable strike off bar is set at an elevation so as to meter the material to the rotary compactor and to achieve the desired compaction for the particular thickness of the finished mat being laid. The rotary compactor then impacts the mat in an essentially vertical direction and so as to achieve complete compaction of the mix.
    Type: Grant
    Filed: May 5, 1992
    Date of Patent: September 20, 1994
    Assignee: Astec Industries, Inc.
    Inventor: Thomas R. Campbell
  • Patent number: 5315770
    Abstract: A self propelled apparatus for digging a shallow trench along one side of a roadway is disclosed, and which is useful as part of a roadway widening operation. The apparatus comprises a cutter drum mounted to one side of the chassis of the apparatus, and a conveyor belt is mounted to the same side of the chassis with an inlet end positioned immediately adjacent the cutter drum and an elevated outlet end positioned beyond the forward end of the chassis. An enclosure surrounds the cutter drum so that the drum may be rotated in a downwardly cutting direction, and the loosened soil or other material may be lifted and guided around the drum and deposited onto the conveyor. The cutter drum includes one or more extensions which may be coaxially mounted thereto, so as to permit the width of the cutter drum and thus the width of the resulting trench to be selectively varied.
    Type: Grant
    Filed: December 15, 1992
    Date of Patent: May 31, 1994
    Assignee: Astec Industries, Inc.
    Inventor: Thomas R. Campbell
  • Patent number: 5078540
    Abstract: A cutter drum of the type adapted for use in milling a roadway surface is disclosed, and which comprises a plurality of flighting assemblies fixed to the surface of the drum in a helical configuration. Each flighting assembly comprises a base plate which is aligned with a plane which perpendicularly intersects the central axis of the drum, and rear and forward support blocks fixed to one side of the base plate to define a channel therebetween. A tooth holder is mounted in the channel, and the holder has an outer portion which extends radially above the outer edge of the base plate, and the tooth holder is releasably mounted in the channel by means of a bolt. The portion of the tooth holder in the channel is protectively covered by the side surface of the base plate of an adjacent assembly.
    Type: Grant
    Filed: August 24, 1990
    Date of Patent: January 7, 1992
    Assignee: Astec Industries, Inc.
    Inventors: Herbert E. Jakob, Thomas R. Campbell
  • Patent number: 4565252
    Abstract: A borehole operating tool such as an underreamer or milling tool for performing borehole expanding or cutting operations in an oil well borehole, the tool including an elongated cylindrical housing having a main bore and side openings in which expandable arms are mounted for pivotal movement between closed and opened positions by a pivot pin; a piston element is mounted within the main bore of the housing for moving to an actuated position holding the expandable arms in an outer, expanded position; and a rotary fluid housing is mounted within each expandable arm about the hinge pin and includes a body nozzle for receiving fluid from the body and an expandable arm nozzle for directing fluid into a bore which extends through the expandable arm to thereby provide circulating fluid outwardly of the expandable arm in order to keep the operating outer end area of the expandable arm from becoming clogged.
    Type: Grant
    Filed: March 8, 1984
    Date of Patent: January 21, 1986
    Assignee: LOR, Inc.
    Inventors: Thomas R. Campbell, William L. Cunningham, Gregg S. Perkin