Did You Know...
...that the inventor of the electric motor was a blacksmith named Thomas Davenport? Described as "a brilliantly unsuccessful inventor", Davenport invented the first rotary electric motor. In 1836 he headed out -- on foot -- from his Vermont home to file a patent application at the Patent Office in Washington, D.C. By the time he got there, he had squandered away his money and couldn't afford the $30 filing fee so he turned around and went home. When he later mailed in his application with money he'd raised, the Patent office was destroyed in a fire. He did finally get credit for his invention on Feb. 5, 1837.
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| Number | Title | Issue Date |
| 8067909 | Method and apparatus for electromagnetically braking a motor An electromagnetic braking system and method is provided for selectively braking a motor using an electromagnetic brake having an electromagnet, a permanent magnet, a rotor assembly, and a brake pad. The brake assembly applies when the electromagnet is de-energized ... | 11/29/2011 |
| 7659677 | Rotation brake method and device for working machine To stop, in an emergency, a revolving superstructure quickly from rotating while preventing damage of a mechanical brake. A revolving superstructure is driven swiveling using a permanent magnetic-type swiveling electric motor; in an emergency, such as a malfunction ... | 02/09/2010 |
| 7498756 | Braking system for electric step motors A braking system for electric step motors that operate in conjunction with a light assembly, including a moving head for pan or tilt thereof or for moving internal optical components. The step motors are connected to driving means to reduce movement speed of the mov... | 03/03/2009 |
| 7423393 | Car control method and car control apparatus A car control apparatus including a wheel sensor, wheel torque calculating means for calculating wheel torque from the wheel speed, drive force detecting means for detecting drive force generated by an electric motor, car body drive force calculating means for calcu... | 09/09/2008 |
| 7362071 | Rotation control device, rotation control method and construction machine In an electric rotary excavator (construction machine) 1, when earth pressure acts on a rotary body 4 in an opposite direction to an instructed direction of a lever, a control-system changing means 150 of a rotation control device 100 inc... | 04/22/2008 |
| 7327110 | Drive circuit for braking a motor during a malfunction A drive system with an electric motor is described, which includes an integrated armature short-circuit brake and a mechanical brake. If the electric motor cannot be controllably slowed down, a control signal is applied at an activation time to the integrated armatu... | 02/05/2008 |
| 7291996 | Optical disc drive and brake control method thereof An optical disc drive 1 includes a spindle motor 11 for rotating the optical disc 2 and a spindle driver for driving the spindle motor 11 equipped with a rotation number counter 232 for measuring the rotation number of the spindle ... | 11/06/2007 |
| 7291997 | Servo system A motor has built therein a brake for stopping the rotation of the motor and a brake controlling circuit for controlling the brake. The motor is further provided with a bypass circuit for supplying an electric power directly to the brake and a terminal for connectin... | 11/06/2007 |
| 7285926 | System and method for locomotive adhesion control A traction control system for controlling an electric traction motor drivingly coupled to a wheel of a tractive vehicle. The traction control system includes means for determining speed of the wheel, means for determining tractive effort of the wheel and a control c... | 10/23/2007 |
| 7248942 | Airflow detection system having an airflow indicating device According to an embodiment, the present invention pertains to a system for detecting airflow in a room. The system includes an airflow indicating device having a movable component whose movement substantially corresponds to airflow in a vicinity of the airflow indic... | 07/24/2007 |
| 7190133 | Energy storage system and method for hybrid propulsion A hybrid propulsion system. The system comprises one or more hybrid propulsion traction drives having an electric motor operable to produce mechanical power for propulsion. A hybrid propulsion traction drive is operable to receive power from an on-board power genera... | 03/13/2007 |
| 7176645 | Control apparatus for electric railcar A control apparatus for an electric railcar that provides control so that when rotational speed of a motor decreases below a required value, torque of the motor will decrease at a required rate of change, a current limiter for limiting a torque current command “(A... | 02/13/2007 |
| 7166977 | Indurstrial robot controlling device Since a release voltage to a brake is applied by a plurality of series-connected contacts and at least one contact is a normally open contact of a relay for controlling a driving power supply of a motor, a control apparatus having a high safety characteristic for an... | 01/23/2007 |
| 7148652 | Method and apparatus for determining and handling brake failures in open loop variable frequency drive motors A controller for a variable frequency drive monitors electrical power from a variable frequency drive motor while a brake is maintaining a load driven or moved by the motor without requiring additional feedback components of a closed loop configuration. If excess el... | 12/12/2006 |
| 7073872 | Motor driving apparatus and disk apparatus using the same A motor driving apparatus includes a position detector for detecting a rotational position of a motor to output the detection result as a position signal, a frequency comparator for comparing frequencies of continuous periods in the position signal and detecting a r... | 07/11/2006 |
| 7071645 | Braking device for an electric motor, electrical apparatus provided with the braking device, and a method of braking A braking device for an electric motor of a power tool has a short circuit switch for short circuiting an armature winding of the electric motor during a braking process, the short circuit switch for controlling its switch condition having a control input, a control... | 07/04/2006 |
| 7072739 | Data center robotic device A method for operating a data center with a robotic device. In the method, a condition is detected in a location of the data center. The robotic device, which includes a camera and a manipulator, is maneuvered to travel to the location of the data center. The locati... | 07/04/2006 |
| 7034480 | Method for eliminating fuel use during dynamic braking A method for reducing engine fuel consumption of an electro-motive vehicle during braking, the method including steps for providing an engine for the vehicle, generating primary electric power at a primary electric power generator connected to the engine, generating... | 04/25/2006 |
| 7012392 | Multi-stage dynamic braking resistor network A multi-stage dynamic braking resistor network (23) is provided that includes a plurality of dynamic brake resistors (1a–d) for dissipating, as heat, regenerative energy inputted onto a system bus (17) by a motor or actuator (19)... | 03/14/2006 |
| 6922032 | Electric motor control device In the driving operation of a sensorless three-phase motor to be used in a rotation at a comparatively low speed (approximately 2000 RPM or less) and to be bipolar driven, the number of rotations and a rotating position are accurately detected from an induced voltag... | 07/26/2005 |
| 6822408 | Method of securing a machine element and/or a load connected to the machine element in a fixed position In a method of holding a machine element, whose position is directly or indirectly controlled by an electromotive drive in the absence of a self-locking mechanism, the drive is halted and a brake is activated to maintain the machine element in a holding position, wi... | 11/23/2004 |
| 6739675 | Brake effort monitor A brake effort monitor for railcar braking systems includes means connected to receive a brake effort request signal and a vehicle speed signal for generating an energy requested signal. Another device is connected to receive a brake effort actual signal and a vehic... | 05/25/2004 |
| 6531839 | Circuit and method for motor control Disclosed is an optimized brake method for braking a motor rotating at a high speed. When the motor rotates at the high speed, the present invention reduces the rotation speed of the motor using a mechanical brake method which has a relatively high rate o... | 03/11/2003 |
| 6459224 | Zone control method in roller conveyor and zone controller In a roller conveyor system for carrying out zone control, a conveyed article can be stopped in an approximately constant position without varying the position where the article is stopped in a desired control zone even if the weight of the article varies... | 10/01/2002 |
| 6424798 | Device for controlling sensorless brushless-DC-motor A sensorless brushless-DC-motor mounted on an electric or hybrid vehicle is powered by an on-board battery through an inverter supplying a three-phase pulse width modulated voltage (PWM voltage). The inverter is controlled to generate the PWM voltage havi... | 07/23/2002 |
| 6347681 | Electrically integrated scooter with dual suspension and stowage mechanism An electric scooter having batteries concealed below the standing platform in a multipurpose battery pan, an anti-lock brake, a dual suspension, a stow and carry feature, integrated electronics including brake control, throttle control, safety measures an... | 02/19/2002 |
| 6310452 | Single cycle positioning system utilizing a DC motor A single cycle positioning system utilizing a DC motor wherein a wide ranging incoming AC supply voltage is rectified and a fixed frequency variable duty cycle pulse width modulation is provided to apply a predetermined rms DC voltage to the motor for a s... | 10/30/2001 |
| 6294887 | Motor brake device for a robot A brake release circuit of an electromagnetic brake for locking a motor and an indication circuit for indicating a brake release are coupled together. Both the circuits may be turned on and off by a single switch contact. A motorbrake release device secur... | 09/25/2001 |
| 6213571 | Control apparatus for an electric vehicle and a method therefor Problems of a dead-time due to a make-contact delay time until the closure of the regeneration contactor and a drop of torque occurring in the prior art controller for an electric vehicle are solved by the invention, thereby providing an improved drive fe... | 04/10/2001 |
| 6097165 | Method and apparatus for handling brake failure in variable frequency drive motors The variable frequency drive of a motor monitors pulse generator feedback while the motor is stopped and an electromechanical brake is set. When the pulse generator feedback exceeds a predetermined level indicative of brake failure, tie controller actuate... | 08/01/2000 |
| 6047534 | Stopping and restarting device in independent driven spindle in spinning machine Regarding an independently driven type spindle in a spinning machine, when a yarn breakage is occurred in a spindle 10, a brake operating member 35 of the spindle 10 is moved toward a spindle shaft 13. During the movement of the brake operating member 35,... | 04/11/2000 |
| 6040561 | High voltage bus and auxiliary heater control system for an electric or hybrid vehicle A control system for an electric or hybrid electric vehicle includes a vehicle system controller and a control circuit having an electric immersion heater. The heater is electrically connected to the vehicle's high voltage bus and is thermally coupled to ... | 03/21/2000 |
| 5892341 | Quick set electric motor brake control A control circuit (10) is provided for an electric motor brake (12) having an electromagnetic brake coil (14) energizable to actuate the brake to a released condition permitting rotation of an electric motor (16), and de-energizable to enable actuation of... | 04/06/1999 |
| 5853229 | Method and apparatus for controlling the brake system of motor vehicles with electric drive In a first region of the driver's braking command, regenerative braking produces almost all of the braking torque, whereas the friction brake produces essentially no braking torque. In this region of the braking command, the pressure medium flowing into t... | 12/29/1998 |
| 5811947 | Testing and speed control of electric motors in vehicles having electronically controlled braking systems A vehicle anti-lock braking (ABS) system having a motor-driven pump (10) for providing a hydraulic supply to the ABS system. The pump motor (10) is controlled by a series device in the form of an electronic switch (16), such as a MOSFET, to enable frequen... | 09/22/1998 |
| 5751127 | Magnet brake A magnet brake is disclosed. The magnet brake may consist of a stationary magnet assembly and a rotating magnet assembly. The opposing poles on the magnet assemblies have a mutual attraction that biases the assemblies into alignment with each other. The m... | 05/12/1998 |
| 5654613 | Over drive control apparatus of direct current series motor The invention is made to provide a reliable driving system by solving the problem of the conventional apparatus caused by unstable current in the chopper transistor located at the low end of the field winding and armature winding. The over drive control a... | 08/05/1997 |
| 5583406 | Control method and system for regeneration braking of an electric vehicle When a voltage level determinator judges from the terminal voltage of a smoothing capacitance that a battery is in an over-charged state and cannot receive regeneration energy, a regeneration/free-wheel mode selector switches to a free-wheel mode for cons... | 12/10/1996 |
| 5530328 | Consist power monitor A consist power monitor provides information to the engineer of a multiple unit consist on the ability of each locomotive to provide traction power and dynamic braking. The consist power monitor is a microprocessor based device which communicates with oth... | 06/25/1996 |
| 5524541 | Method and apparatus for controlling the braking of a printing machine A description of a method and a device for monitoring the braking of a D.C. motor of a printing machine such as a sheet-fed offset printing machine is given. For safety purposes, in the case of an emergency stop an electrical braking should always be carr... | 06/11/1996 |
