Patents by Inventor Robert E. Crandall

Robert E. Crandall 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: 4681033
    Abstract: In a belt press of the type used to dewater heavy slurries, an improved belt drive system is provided. The upper belt is driven by at least two rollers, one of which is situated in the dewatering section wherein the upper and lower belts are squeezed and traveling together. The improved drive arrangement provides a more uniformly increasing tension in the belt as it passes through the dewatering section than in such presses heretofore. Further because the lower belt is at least partially driven by its frictional engagement with the upper belt, through the sandwiched slurry, the synchronization of the belt speeds is improved. Further improved control of the belt press performance is provided by means for sensing the speeds of the belts and responsive means for regulating the belt tensioning systems accordingly.
    Type: Grant
    Filed: July 23, 1986
    Date of Patent: July 21, 1987
    Assignee: Rexnord Inc.
    Inventors: Robert E. Crandall, Kenneth F. Kosulic, Thomas C. Rooney, Larry C. Smith
  • Patent number: 4629061
    Abstract: A belt steering control system for a belt press having a frame and a plurality of rolls around which a pair of belts passes, said system comprising a paddle-type belt edge position sensor lightly biased against the edge of the belt for sensing the actual position of the belt edge and producing an error signal indicative of the deviation of the belt edge relative to its position where the belt is centered; the paddle sensor being connected by a control shaft to a rotary drive transfer means; the drive transfer means transmitting movement of the paddle sensor to a rotary hydraulic valve by means of a variably tensioned, spring-loaded disc which engages the rotary drive transfer means; a belt steering roll around which the belt is trained and having two ends mounted in bearings on the frame, one of the ends being mounted for translation relative to the frame; and a steering roll actuator which is controlled by the rotary hydraulic valve and skews the steering roll when necessary to maintain proper belt tracking.
    Type: Grant
    Filed: April 22, 1985
    Date of Patent: December 16, 1986
    Assignee: Rexnord Inc.
    Inventor: Robert E. Crandall
  • Patent number: 4622894
    Abstract: In a belt press of the type used to dewater heavy slurries, an improved belt drive system is provided. The upper belt is driven by at least two rollers, one of which is situated in the dewatering section wherein the upper and lower belts are squeezed and traveling together. The improved drive arrangement provides a more uniformly increasing tension in the belt as it passes through the dewatering section than in such presses heretofore. Further because the lower belt is at least partially driven by its frictional engagement with the upper belt, through the sandwiched slurry, the synchronization of the belt speeds is improved. Further improved control of the belt press performance is provided by means for sensing the speeds of the belts and responsive means for regulating the belt tensioning systems accordingly.
    Type: Grant
    Filed: December 11, 1984
    Date of Patent: November 18, 1986
    Assignee: Rexnord Inc.
    Inventors: Robert E. Crandall, Kenneth F. Kosulic, Thomas C. Rooney, Larry C. Smith
  • Patent number: 4584936
    Abstract: A belt press for dewatering slurries is described having a frame designed to minimize the time, effort and frame stress heretofore encountered in the replacement of endless belts, said press comprising a rigid frame comprised of essentially parallel horizontal and vertical members supporting a plurality of laterally oriented longitudinal rolls upon which a pair of endless flat foraminous belts pass in a serpentine path with dewatered material sandwiched therebetween. The frame is equipped with vertical legs having removable spacers on one side and corresponding elastomeric hinges mounted with pre-stressed bolts, and alignment pins on the other side. Jack means positionable between the sides of the frame, co-operate with the pre-stressed bolts to permit removal of the frame spacers and extraction of the endless belts through the resulting gaps in the vertical legs.
    Type: Grant
    Filed: December 11, 1984
    Date of Patent: April 29, 1986
    Assignee: Rexnord Inc.
    Inventors: Robert E. Crandall, Roger B. Nickolaus
  • Patent number: 4544061
    Abstract: A conveyor belt tensioning system having two fluid piston and cylinders units on each lateral side of the belt. The units are parallel to each other and are attached to a tensioning roll. A pair of cables are attached to both of the pistons and pass around pulleys in a manner as to compensate for any differences in force between the pistons such that the pistons move in the same direction the same amount.
    Type: Grant
    Filed: October 11, 1983
    Date of Patent: October 1, 1985
    Assignee: Rexnord Inc.
    Inventor: Robert E. Crandall
  • Patent number: 4305821
    Abstract: A hinged doctor blade is biased to its operative position respecting the belt of a belt conveyor. Shoes at each end of the blade ride on the belt ahead of the blade respecting belt travel and are positioned and connected to the blade so that the forward clips of the belt joint lifts the blade upon the first approach of either end of the joint and the other end is effective to hold the doctor blade in its raised position until the forward portion of the seam is beneath the blade and the blade can safely ride over the seam and then resume its operative position respecting the filter belt. Adjustment means are provided so that the positions of the shoes relative to the doctor blade may be set as required by the length of the seam having reference to the direction of belt travel.
    Type: Grant
    Filed: December 11, 1980
    Date of Patent: December 15, 1981
    Assignee: Envirex Inc.
    Inventors: Robert E. Crandall, Bert Krivec
  • Patent number: 3989627
    Abstract: A diffuser assembly of the general type for use in a municipal sewage treatment plant is of plastic and/or resin construction and includes spaced parallel or dual hanger pipes between the two rotary joints. The hoist arm extends between these hanger pipes to reach the lift joint. Opposed detent blocks between and engaging the dual pipes cooperate with a steady bracket into which the assembly is locked with a toggle action.
    Type: Grant
    Filed: September 30, 1975
    Date of Patent: November 2, 1976
    Assignee: Envirex Inc.
    Inventor: Robert E. Crandall