Patents by Inventor David B. Mohler

David B. Mohler 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: 7880410
    Abstract: An actuator (20) comprises a rotor (22); an electromagnetic circuit (24) configured to produce bidirectional torque on the rotor; and, a rotation limitation assembly (26). The rotor (22) comprises a rotor shaft and plural magnets (80) affixed to the rotor shaft. In an example embodiment the rotation limitation assembly (26) comprises at least one stationary clockwise boundary (40) configured to limit clockwise rotation of the rotor (22); at least one stationary counterclockwise boundary (42) configured to limit counterclockwise rotation of the rotor (22); and a rotor stop arm (50) connected to the rotor and configured to selectively abut the clockwise boundary (40) and the counterclockwise boundary (44) and thereby limit the rotation of the rotor to a predetermined angle about an axis of the rotor shaft.
    Type: Grant
    Filed: March 19, 2008
    Date of Patent: February 1, 2011
    Assignee: Saia-Burgess, Inc.
    Inventor: David B. Mohler
  • Patent number: 7839041
    Abstract: Embodiments of actuators (20) comprise an electromagnetically conductive housing (22); a rotor (24); a first stationary pole member (48); a second stationary pole member (42); a first permanent magnet (44) connected to the first pole member (48); a second permanent magnet (46) connected to the first pole member (48); and; an electrically conductive coil (40) situated within the housing (22) and configured to define a cavity. The rotor (24) comprises a rotor shaft (26) and a rotor flange (28). The rotor flange (28) comprises both a first flange segment (56) and a second flange segment (58) which extend in different radial directions relative to the rotor shaft (26).
    Type: Grant
    Filed: March 3, 2009
    Date of Patent: November 23, 2010
    Assignee: Saia-Burgess Inc.
    Inventor: David B Mohler
  • Publication number: 20090218902
    Abstract: Embodiments of actuators (20) comprise an electromagnetically conductive housing (22); a rotor (24); a first stationary pole member (48); a second stationary pole member (42); a first permanent magnet (44) connected to the first pole member (48); a second permanent magnet (46) connected to the first pole member (48); and; an electrically conductive coil (40) situated within the housing (22) and configured to define a cavity. The rotor (24) comprises a rotor shaft (26) and a rotor flange (28). The rotor flange (28) comprises both a first flange segment (56) and a second flange segment (58) which extend in different radial directions relative to the rotor shaft (26).
    Type: Application
    Filed: March 3, 2009
    Publication date: September 3, 2009
    Inventor: David B. MOHLER
  • Publication number: 20080238348
    Abstract: An actuator (20) comprises a rotor (22); an electromagnetic circuit (24) configured to produce bidirectional torque on the rotor; and, a rotation limitation assembly (26). The rotor (22) comprises a rotor shaft and plural magnets (80) affixed to the rotor shaft. In an example embodiment the rotation limitation assembly (26) comprises at least one stationary clockwise boundary (40) configured to limit clockwise rotation of the rotor (22); at least one stationary counterclockwise boundary (42) configured to limit counterclockwise rotation of the rotor (22); and a rotor stop arm (50) connected to the rotor and configured to selectively abut the clockwise boundary (40) and the counterclockwise boundary (44) and thereby limit the rotation of the rotor to a predetermined angle about an axis of the rotor shaft.
    Type: Application
    Filed: March 19, 2008
    Publication date: October 2, 2008
    Applicant: SAIA-BURGESS, INC.
    Inventor: David B. Mohler
  • Patent number: 6756873
    Abstract: A rotary actuator (16) includes a rotor (48) which is disposed in a housing (34) between first and second pole pieces (42 and 44) of a stator (40). The rotor (48) is rotatable relative to the stator (40) between an unactuated position (FIG. 4) and an actuated position (FIG. 5). During rotation of the rotor (48), the axial extent of a first working air gap (66) between the rotor and a first pole piece (44) of the stator (40) remains constant. However, the axial extent of the working air gap (64) between the rotor (48) and the second pole piece (42) of the stator (40) decreases as the rotor moves from the unactuated position to the actuated position. In a preferred embodiment, the rotor lobes are made so that the net axial force of all of the rotor lobes is substantially zero thereby reducing stress on the rotor shaft support bearings.
    Type: Grant
    Filed: September 12, 2001
    Date of Patent: June 29, 2004
    Assignee: SAIA-Burgess Inc.
    Inventor: David B. Mohler
  • Patent number: 6507257
    Abstract: A bi-directional latching actuator is comprised of an output shaft with one or more rotors fixedly mounted thereon. The shaft and rotor are mounted for rotation in a magnetically conductive housing having a cylindrical coil mounted therein and is closed by conductive end caps. The end caps have stator pole pieces mounted thereon. In one embodiment, the rotor has at least two oppositely magnetized permanent magnets which are asymmetrically mounted, i.e., they are adjacent at one side and separated by a non-magnetic void on the other side. The stator pole piece has asymmetric flux conductivity and in one embodiment is axially thicker than the remaining portion of the pole piece. An abutment prevents the rotor from swinging to the neutral position (where the rotor magnets are axially aligned with the higher conductivity portion of the pole piece). Thus, the rotor is magnetically latched in one of two positions being drawn towards the neutral position.
    Type: Grant
    Filed: March 30, 2001
    Date of Patent: January 14, 2003
    Assignee: SAIA-Burgess Inc.
    Inventor: David B. Mohler
  • Patent number: 6469885
    Abstract: An electronic driver circuit for reducing power consumed by a solenoid operated device. The end of the solenoid operating stroke or the existence of suitable kinetic energy in a solenoid armature is measured by reference to current flow through the solenoid coil. Current flow through the solenoid coil is subsequently terminated so as to avoid further power waste which is not contributing to any desirable increase in armature kinetic energy. In a preferred embodiment, the magnetic flux built up in the solenoid coil is applied through a suitable diode network back to the power supply, thereby reducing further the power requirements for solenoid operation.
    Type: Grant
    Filed: February 16, 2000
    Date of Patent: October 22, 2002
    Assignee: Impact Devices Incorporated
    Inventor: David B. Mohler
  • Publication number: 20020030572
    Abstract: A rotary actuator (16) includes a rotor (48) which is disposed in a housing (34) between first and second pole pieces (42 and 44) of a stator (40). The rotor (48) is rotatable relative to the stator (40) between an unactuated position (FIG. 4) and an actuated position (FIG. 5). During rotation of the rotor (48), the axial extent of a first working air gap (66) between the rotor and a first pole piece (44) of the stator (40) remains constant. However, the axial extent of the working air gap (64) between the rotor (48) and the second pole piece (42) of the stator (40) decreases as the rotor moves from the unactuated position to the actuated position. In a preferred embodiment, the rotor lobes are made so that the net axial force of all of the rotor lobes is substantially zero thereby reducing stress on the rotor shaft support bearings.
    Type: Application
    Filed: September 12, 2001
    Publication date: March 14, 2002
    Inventor: David B. Mohler
  • Publication number: 20010030479
    Abstract: A bi-directional latching actuator is comprised of an output shaft with one or more rotors fixedly mounted thereon. The shaft and rotor are mounted for rotation in a magnetically conductive housing having a cylindrical coil mounted therein and is closed by conductive end caps. The end caps have stator pole pieces mounted thereon. In one embodiment, the rotor has at least two oppositely magnetized permanent magnets which are asymmetrically mounted, i.e., they are adjacent at one side and separated by a non-magnetic void on the other side. The stator pole piece has asymmetric flux conductivity and in one embodiment is axially thicker than the remaining portion of the pole piece. An abutment prevents the rotor from swinging to the neutral position (where the rotor magnets are axially aligned with the higher conductivity portion of the pole piece). Thus, the rotor is magnetically latched in one of two positions being drawn towards the neutral position.
    Type: Application
    Filed: March 30, 2001
    Publication date: October 18, 2001
    Inventor: David B. Mohler
  • Patent number: 5337030
    Abstract: A permanent magnet brushless torque actuator is comprised of an electromagnetic core capable of generating an elongated toroidally shaped magnet flux field when energized. Outside the generally cylindrical coil is an outer housing with upper and lower end plates at each end. Mounted to the end plates and extending towards each other are stator pole pieces separated from its opposing pole piece by an air gap. A permanent magnet rotor is disposed in the air gap and mounted on a shaft which in turn is rotatably mounted in each of the end plates. The permanent magnet rotor comprises at least two permanent magnets, each covering an arcuate portion of the rotor and having opposite polarities. Energization of the coil with current in one direction magnetizes the pole pieces such that each of the two pole pieces attracts one of the magnets of the rotor and repels the other magnet of the rotor resulting in a torque generated by the output shaft.
    Type: Grant
    Filed: October 8, 1992
    Date of Patent: August 9, 1994
    Assignee: Lucas Industries, Inc.
    Inventor: David B. Mohler
  • Patent number: 5161083
    Abstract: Disclosed is an improved solenoid actuator utilizing an actuator position sensor which in combination with an actuator controller, adjusts the energizing current supplied to the actuator's coil. The adjustment is based upon any difference between an actual position of the actuator and a desired position of the actuator. If there is a difference, the controller changes the energization of the actuator's coil so as to actively move the actuator to the desired position. The improvement can be utilized with existing rotary and linear proportional actuators as well as any other solenoid-type actuator.
    Type: Grant
    Filed: September 9, 1991
    Date of Patent: November 3, 1992
    Assignee: Lucas Ledex Inc.
    Inventors: David B. Mohler, Randy S. Robinson
  • Patent number: 4855700
    Abstract: Disclosed is a dual working airgap force motor. A centrally located stator includes two toroidally shaped electromagnets wherein the axis of the stator coincides with the axis of the toroids, each toroidal coil is separated from the other toroidal coil by an axial distance. Toroidal permanent magnets are also mounted preferably inside the toroidal electromagnet coils and also spaced apart in an axil direction. The permanent magnets generate a flux flow in opposite axial directions whereas, upon energization, the toroidal coils generate flux flow in the same axial direction at a given radial position. Two armatures are located on an output shaft, in a preferred embodiment at either end of the stator, and each armature is spaced apart from the stator by inner and outer axial airgaps.
    Type: Grant
    Filed: February 16, 1989
    Date of Patent: August 8, 1989
    Assignee: Lucas Ledex Inc.
    Inventor: David B. Mohler
  • Patent number: 4847581
    Abstract: Disclosed is a dual working airgap force motor. A centrally located stator includes two toroidally shaped electromagnets wherein the axis of the stator coincides with the axis of the toroids, each toroidal coil is separated from the other toroidal coil by an axial distance. Toroidal permanent magnets are also mounted preferably inside the toroidal electromagnet coils and also spaced apart in an axial direction. The permanent magnets generate a flux flow in opposite axial directions whereas, upon energization, the toroidal coils generate flux flow in the same axial direction at a given radial position. Two armatures are located on an output shaft, in a preferred embodiment at either end of the stator, and each armature is spaced apart from the stator by inner and outer axial airgaps.
    Type: Grant
    Filed: August 1, 1988
    Date of Patent: July 11, 1989
    Assignee: Lucas Ledex Inc.
    Inventor: David B. Mohler
  • Patent number: 4812884
    Abstract: Disclosed is a solenoid having a central and a peripheral air gap between the armature and the pole piece. The energizating coil is located in the space between the central core and the peripheral portions of the pole piece and armature. In one embodiment, an output shaft is received in an aperture in the central core of the pole piece and connected to the armature. In preferred embodiments, a longitudinally and radially extending slot is provide to produced eddy current losses. Additionally, mass is removed from non-critical portions of the armature to reduce its weight and increase its acceleration during energization of the solenoid. By utilizing stepped changes in the pole piece and armatures, peripheral portions and central core portions as well as variations in the central and peripheral gaps, the force/distance curve of the solenoid can be tailored to the specific application.
    Type: Grant
    Filed: June 26, 1987
    Date of Patent: March 14, 1989
    Assignee: Ledex Inc.
    Inventor: David B. Mohler
  • Patent number: 4235114
    Abstract: A testing device for applying a force to a material test sample includes a test fixture for engaging the test sample and a solenoid, operatively coupled to the test fixture, for applying a predetermined force to the test sample in response to a solenoid control signal. A strain gauge is mounted on the test fixture and provides an electrical output indicative of the force applied to the test sample. A force setting circuit provides an electrical output indicative of the predetermined force which is to be applied to the test sample. A solenoid control circuit is responsive to the output from the strain gauge element and to the output of the force setting element and provides a control signal to the solenoid such that the predetermined force may be applied to the test sample. The force setting circuit provides an electrical output having an adjustable rate of increase and an adjustable maximum level. A sample circuit monitors the output of the strain gauge to store the peak force applied to the test sample.
    Type: Grant
    Filed: April 2, 1979
    Date of Patent: November 25, 1980
    Assignee: Ledex, Inc.
    Inventor: David B. Mohler
  • Patent number: RE40503
    Abstract: A rotary actuator (16) includes a rotor (48) which is disposed in a housing (34) between first and second pole pieces (42 and 44) of a stator (40). The rotor (48) is rotatable relative to the stator (48) between an unactuated position (FIG. 4) and an actuated position (FIG. 5). During rotation of the rotor (48), the axial extent of a first working air gap (66) between the rotor and a first pole piece (44) of the stator (40) remains constant. However, the axial extent of the working air gap (64) between the rotor (48) and the second pole piece (42) of the stator (40) decreases as the rotor moves from the unactuated position to the actuated position. In a preferred embodiment, the rotor lobes are made so that the net axial force of all of the rotor lobes is substantially zero thereby reducing stress on the rotor shaft support bearings.
    Type: Grant
    Filed: September 29, 2005
    Date of Patent: September 16, 2008
    Assignee: SAIA-Burgess Inc.
    Inventor: David B. Mohler