Patents Assigned to Robbins & Myers, Inc.
  • Patent number: 6120267
    Abstract: A progressing cavity pump in which portions of the stator have been removed or cut away so as to provide a degree of radial access to the cavities formed by the pump elements within the progressing cavity pump suction chamber. One embodiment of such a stator includes a removed portion which results from a planar cut that starts from the suction end of the stator, proximal the central axis of the internal stator bore, is angled towards the discharge end of the stator and outwardly away from the central axis, and intersects an internal helical groove of the stator that defines a first cavity. In another embodiment of the stator, the removed portion of the stator is a radial "cut-out" which follows the internal helical groove of the stator.
    Type: Grant
    Filed: April 1, 1998
    Date of Patent: September 19, 2000
    Assignee: Robbins & Myers, Inc.
    Inventor: Steven L. Cunningham
  • Patent number: 5820354
    Abstract: At least two progressing cavity pumps or pump sections are connected in series. The flow volume rate of the second pump or pump section is less than the flow volume rate of the first pump or pump section. If there are more than two pumps or pumps sections, the flow volume rate of the third pump or pump section would be less than the flow volume rate of the second pump or pump section, and so on. The cascade arrangement of progressing cavity pumps can be achieved by interconnecting separate pump assemblies end to end. The cascade arrangement of progressing cavity pump sections can be achieved by the attachment of the rotor/stator pairs of each pump section in series with suitable universal mechanisms and housings. Such a cascade arrangement of progressing cavity pumps or pump sections allows and compensates for the compressibility of the gas in the two-phase or multi-phase fluid being pumped, especially in pumping operations requiring high differential pressures.
    Type: Grant
    Filed: November 8, 1996
    Date of Patent: October 13, 1998
    Assignee: Robbins & Myers, Inc.
    Inventors: Alan G. Wild, Kamran Z. Mirza, Sheldon S. L. Chang
  • Patent number: 5803601
    Abstract: A fluid mixing system including a fluid mixing device and method for generating and maintaining a substantially uniform, horizontal velocity profile in a fluid circulation system, such as a plug flow reactor, which requires less horsepower than conventional fluid mixing systems without losing mixing effectiveness. The fluid mixing device employs a top-entry, vertically-oriented impeller and a housing that directs the pumped flow in a generally horizontal direction.
    Type: Grant
    Filed: October 7, 1996
    Date of Patent: September 8, 1998
    Assignee: Robbins & Myers, Inc.
    Inventor: David D. Dean
  • Patent number: 5722820
    Abstract: A progressing cavity pump is provided in which the compressive fit between the rotor and stator is gradually reduced with the distance from the suction end of the pump. This gradual decrease in compressive fit allows for increased slippage near the discharge end of the pump, resulting in better distribution of the internal differential pressure along the length of the pump. The differential pressure distribution in turn reduces heat build-up near the discharge end, increasing the life of the elastomeric stator or rotor.
    Type: Grant
    Filed: May 28, 1996
    Date of Patent: March 3, 1998
    Assignee: Robbins & Myers, Inc.
    Inventors: Alan G. Wild, Kamran Z. Mirza
  • Patent number: 5688114
    Abstract: A progressing cavity pump comprises an inlet housing defining a chamber, an extension tube defining a tube interior communicating with the chamber, a stator defining an internal passageway communicating with the tube interior, a rotor positioned in the internal passageway in abutment against an inner surface of the internal passageway and a coupling at least partially enclosed by the extension tube. The coupling is connected to the rotor for actuating the rotor for rolling movement along the inner surface of the internal passageway of the stator. In an especially preferred form, the extension tube is in the form of a surface of revolution and is separable into first and second sections along a dividing plane which passes through the center of the tube. Fasteners are used to removably fasten the first and second sections to each other, the housing and the stator casing to provide access for inspection of the coupling, the rotor and the stator.
    Type: Grant
    Filed: March 20, 1996
    Date of Patent: November 18, 1997
    Assignee: Robbins & Myers, Inc.
    Inventors: John A. Millington, Alan G. Wild
  • Patent number: 5303933
    Abstract: A shut-off seal for a rotatable shaft penetrating a fluid-holding tank through an opening below the fluid surface. The shut-off seal has a collar secured to the shaft inside the tank and a positionable annular shut-off ring which may be moved into engagement with the collar. The invention enables leakage-free shutdown for servicing an associated rotary seal without moving the rotary seal axially along the shaft.
    Type: Grant
    Filed: July 9, 1992
    Date of Patent: April 19, 1994
    Assignee: Robbins & Myers, Inc.
    Inventor: David J. Larkins
  • Patent number: 5108273
    Abstract: A pump assembly includes commonly driven coaxially positioned helical rotors, rotatably engageable within corresponding stators. Each combination of rotor and stator defines a pump having a different volumetric flow rate, each pump discharging to a common discharge port, thereby providing an accurately proportioned mixed fluid of two separate fluids. The rotors are integrally molded from a thermoplastic material and include an integral drive shaft suitable for interconnection to an electric motor. The two rotors are simultaneously driven by a common drive shaft and therefore produce a constant mixed ratio irrespective of rotational speed.
    Type: Grant
    Filed: August 30, 1990
    Date of Patent: April 28, 1992
    Assignee: Robbins & Myers, Inc.
    Inventor: Michael T. Romanyszyn, Jr.
  • Patent number: 5057684
    Abstract: An apparatus and method is disclosed for centering a pattern wheel of a modular optical shaft encoder and setting a predetermined gap distance between the pattern wheel and a mask and photodetector. The apparatus is built in to the encoder and facilitates aligning and gapping of the pattern wheel with respect to the mask and photodetector during installation of the encoder about a rotatable shaft. The apparatus consists of a slidable linear cam which cooperatively engages a centering collar to urge the collar against a pattern wheel, the pattern wheel is in turn urged into a predetermined position. The collar is retractable from contact with the pattern wheel after the pattern wheel is mounted in position on the rotatable shaft to allow rotation of the wheel and the shaft.
    Type: Grant
    Filed: August 30, 1990
    Date of Patent: October 15, 1991
    Assignee: Robbins & Myers/Electro-Craft, a wholly owned sub. of Robbins & Myers, Inc.
    Inventor: Gregg R. Service
  • Patent number: 4639200
    Abstract: A seal for a gear ball joint in a progressing cavity pump. The seal includes a flexible seal member having a depending flange portion including five sealing surfaces for sealing against mating parts of the joint assembly. The seal also includes an annular stiffening wire molded within the flange portion to provide dimensional stability during seal molding, structural support during assembly and increased working life.
    Type: Grant
    Filed: May 9, 1985
    Date of Patent: January 27, 1987
    Assignee: Robbins & Myers, Inc.
    Inventors: Terry A. Baumgardner, Jere L. Krouse, Alan G. Wild
  • Patent number: 4513994
    Abstract: A ceiling fan and electrical outlet box support for supporting a ceiling fan between a pair of ceiling joists, includes a transversely oriented rigid threaded rod with a joist engaging piece threadedly received on one of the rod for telescopic movement as the rod is rotated, and a second joist engaging piece rotatably mounted on the other end of the rod whereby upon rotation of the rod the joist engaging pieces may be caused to engage the adjacent inside surfaces of a ceiling joist. The rod is rotated by applying a wrench to a pair of nuts which are jammed together over a prepared ceiling opening at some location between the joists. Hanger brackets in the form of eye bolts are slid onto the rod, on either side of the nuts, and support a generally U-shaped ceiling fan support bracket from the rod and also support an electrical junction box. A block of elastomeric material is positioned between the outlet box and the rigid rod, at the driving nuts, to take up vibration and slack.
    Type: Grant
    Filed: January 31, 1983
    Date of Patent: April 30, 1985
    Assignee: Robbins & Myers, Inc.
    Inventors: Donald L. Dover, William J. Leitch
  • Patent number: 4511310
    Abstract: An arrangement for isolating engine noises and vibrations or the like from the blades of a ceiling fan include a blade-mounting ring, to which the blade irons are directly attached, and a plurality of elastomeric grommets or bushings carried on the ring. Partially threaded studs extend through the grommets and into the rotor cage to suspend the blade-mounting ring slightly below the rotor cage by the transfer of weight of the blades through the rubber grommets. The blade-iron feet enclose the grommets and prevent the inadvertent withdrawal of the stud members therefrom.
    Type: Grant
    Filed: March 2, 1984
    Date of Patent: April 16, 1985
    Assignee: Robbins & Myers, Inc.
    Inventor: Richard A. Pearce
  • Patent number: 4475872
    Abstract: A water pump includes a pump stand and a spout mounted on the stand for communication with its interior. A rotary drive shaft supported by the pump stand extends downwardly to an underground water supply. A pump rotor supported by the drive shaft is positioned within a stator communicating with the water supply, for cooperating to pump water to the pump stand and the spout. An input shaft applies a rotary driving motion to a gear box mounted on the pump stand, which in turn applies a rotary driving motion to the drive shaft. The gear box includes first and second bevel gears mounted on the input shaft in a spaced apart relation. A first clutch permits relative rotary motion in a first direction between the input shaft and the first gear while prohibiting relative rotary motion in a second direction. A second clutch permits relative rotary motion between the input shaft and the second bevel gear in the second direction, while prohibiting relative rotary motion in the first direction.
    Type: Grant
    Filed: September 28, 1982
    Date of Patent: October 9, 1984
    Assignee: Robbins & Myers, Inc.
    Inventor: Joan S. Foughty
  • Patent number: 4112786
    Abstract: There is disclosed a housing assembly for gear heads or speed reducers and the like, and a method of assembly of such devices, which eliminates all drilling, tapping, fasteners, shims, gaskets and sealants, as well as doing away with assembly skill, which has been required heretofore to set proper bearing clearance. It is applicable to the assembly of any rotating element, such as a worm wheel, into a housing. The housing may have a bore for the introduction of the rotating element on one side only. The bore is closed by a side plate which fits into the housing with a small clearance and is sealed with an ordinary O-ring. After the rotating element and its bearings have been inserted into the housing and side plate, the side plate is pressed into the bore until zero axial clearance is attained.
    Type: Grant
    Filed: January 19, 1977
    Date of Patent: September 12, 1978
    Assignee: Robbins & Myers, Inc.
    Inventor: Richard J. Thomas
  • Patent number: 4055113
    Abstract: Ventilator apparatus which includes rotary impeller or fan structure and an electric motor for rotation thereof. A shaft joins the rotor of the electric motor to the impeller or fan structure for rotation thereof. The rotor of the electric motor, in addition to being rotatable, is axially movable upon energization thereof. A shroud encompasses the impeller or fan structure. A closure member attached to the shaft is adapted to be closely positioned with respect to the end of the shroud to substantially close the shroud when the apparatus is not in ventilating operation. When the rotor of the electric motor is energized for operation of the impeller, the rotor, in addition to commencing rotation, moves axially and moves the closure member axially to spaced relationship from the shroud, to provide an opening between the shroud and the closure member for flow of air between the shroud and the closure member.
    Type: Grant
    Filed: May 7, 1976
    Date of Patent: October 25, 1977
    Assignee: Robbins & Myers, Inc.
    Inventor: Thomas D. Monroe
  • Patent number: 4025833
    Abstract: The application discloses a thermally actuated switch for electric motors which have some inherent starting torque, such as shaded pole and permanent split capacitor motors. The switch operates only upon abnormal torque demand, to cut out one of the windings of a motor having two windings, or to cut out part of a tapped single winding. The switch normally occupies a first position in which both windings, or the entire winding, are energized. It includes a bimetallic element and a heater coil in series with the windings. Under normal starting and running torque conditions the switch is in the first position, and insufficient heat is generated in the heater coil to trip the switch to its second position. In the event of an abnormal starting or running torque demand, the locked rotor current will persist and will exceed the running current, and heat will be generated in the heater coil.
    Type: Grant
    Filed: May 7, 1975
    Date of Patent: May 24, 1977
    Assignee: Robbins & Myers, Inc.
    Inventor: Charles A. Lawton
  • Patent number: D262570
    Type: Grant
    Filed: June 16, 1980
    Date of Patent: January 5, 1982
    Assignee: Robbins & Myers, Inc.
    Inventor: Gregory J. Lock