Patents by Inventor Stephen M. Sakamoto

Stephen M. Sakamoto 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: 7370697
    Abstract: A thrust section for use above a motor preferably includes a housing, a thrust shaft, a thrust runner connected to the thrust shaft, a thrust bearing connected to the housing, and a motor lead guard. The motor is preferably positioned above a pump assembly. The thrust runner and thrust bearing prevent upward movement of the shaft.
    Type: Grant
    Filed: August 6, 2004
    Date of Patent: May 13, 2008
    Assignee: Wood Group ESP, Inc.
    Inventors: Stephen M. Sakamoto, Aaron Noakes
  • Patent number: 7048046
    Abstract: Preferred embodiments of the present invention provide a submersible pumping system for pumping wellbore fluids. The submersible pumping system includes a rotatable shaft and a mechanical seal that substantially surrounds the shaft. The mechanical seal prevents the flow of wellbore fluid along the shaft and includes a spring, a spring retainer and a runner. The spring surrounds the shaft and provides an axial force along the shaft. The spring retainer is affixed to the shaft and includes a detent to hold the spring. The runner is in interlocking engagement with the spring retainer and accommodates the spring. The interlocking engagement causes the runner to rotate within the spring retainer while permitting axial movement of the shaft relative to the runner.
    Type: Grant
    Filed: November 12, 2003
    Date of Patent: May 23, 2006
    Assignee: Wood Group ESP, Inc.
    Inventor: Stephen M. Sakamoto
  • Patent number: 6857781
    Abstract: A pumping system is provided that includes a pump assembly and a motor assembly. The motor assembly has a bearing collar and a bearing sleeve concentric to the bearing collar. Preferably, the bearing sleeve includes at least one propeller blade that is configured to assist the movement of lubricant through the motor assembly. In another preferred embodiment, the motor includes a lubricant channel housed within a centrally located shaft. Lubricant is moved out of the lubricant channel through a shaft port and a blade port disposed in the propeller blade.
    Type: Grant
    Filed: January 29, 2003
    Date of Patent: February 22, 2005
    Assignee: Wood Group ESP. Inc.
    Inventor: Stephen M. Sakamoto
  • Patent number: 6837621
    Abstract: Disclosed is an improved hydrodynamic bearing assembly for use in a motor assembly. The motor assembly typically includes a shaft with an axially oriented fluid channel and at least one radial shaft port extending through the wall of the shaft. The bearing assembly includes a bearing sleeve and a bearing collar. Preferably, the radial thickness of the bearing sleeve is at least the radial thickness of the bearing collar. It is also preferred that the bearing sleeve includes at least one bearing port that can be aligned with the shaft port to provide a path of fluid travel from inside the axially oriented fluid channel through the bearing sleeve.
    Type: Grant
    Filed: January 29, 2003
    Date of Patent: January 4, 2005
    Assignee: Wood Group ESP, Inc.
    Inventor: Stephen M. Sakamoto
  • Patent number: 6461115
    Abstract: A suction chamber for use in a pumping system has a motor and a pump. The suction chamber is positioned between the motor and the pump in the pumping system and has a seal assembly. The seal assembly seals the shaft to prevent fluid from leaking through a motor end of the suction chamber. The seal assembly may be removed and replaced through the pump, or wet end of the suction chamber so that any parts, including thrust bearing chamber and/or the motor positioned on the motor end of the suction chamber are not moved during the removal and replacement of the sealing assembly. This permits removal and replacement of the sealing assembly without necessitating the need for realigning the motor, thrust bearing chamber and other parts on the motor side of the suction chamber which alleviates the risk of vibration that might occur due to the removal and then improper realignment of the motor, bearings and/or other equipment on the motor side of the suction chamber.
    Type: Grant
    Filed: October 25, 2000
    Date of Patent: October 8, 2002
    Assignee: Wood Group ESP, Inc.
    Inventors: Neil Ferrier, Stephen M. Sakamoto
  • Patent number: 6450782
    Abstract: A pump-motor assembly having a base, a horizontal pump, a pump bracket to attach the pump to the base, a motor to energize the pump and a motor mount with a motor table and a motor platform to support and position the motor. The motor platform has a standard hole pattern for fasteners connecting the motor platform to the motor table. The motor table has a base and an adapter plate with multiple aperture sets standardizing the motor platform height and motor fastener pattern that establish the height of the motor shaft relative to the motor platform. The thickness of the base plate can be varied as necessary to determine a required motor shaft height, thereby accommodating motor sizes within a selected large range of motor sizes.
    Type: Grant
    Filed: May 24, 2000
    Date of Patent: September 17, 2002
    Assignee: Wood Group Esp, Inc.
    Inventor: Stephen M. Sakamoto