Friction Braking Patents (Class 318/372)
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Patent number: 7067999Abstract: In a neutral range preset, there are set a zone for stopping and holding a rotating body only by a mechanical brake, a zone for holding the body only by performing position holding control, and a zone for simultaneously exerting both effects, i.e., the effect of the mechanical brake and the effect of the holding control. On-the-spot holding torque generated when the position holding control is performed is stored. The higher of the on-the-spot holding torque stored and accelerating torque according to an operation amount of the body at a rotation starting time is set as electric motor torque for acceleration. When performing a pressing work including pressing a bucket against an object for work, torque control is carried out according to the operation amount.Type: GrantFiled: April 28, 2003Date of Patent: June 27, 2006Assignees: Kobelco Construction Machinery Co., Ltd., Kobe Steel, Ltd.Inventors: Naoki Sugano, Koji Inoue, Hideaki Yoshimatsu, Mamoru Uejima
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Patent number: 7034482Abstract: Disclosed is a control apparatus for a hybrid vehicle having an engine, a drive motor (3) that regenerates power, and an electric power storage device (6) that gives/receives power to/from the drive motor (3). The control apparatus includes power consumption means (2) for consuming power; a sensor (26, 27) that detects a state of charge of the electric power storage device; means (18, 23, 51) for detecting a driving state of the vehicle; and a controller (9).Type: GrantFiled: February 22, 2005Date of Patent: April 25, 2006Assignee: Nissan Motor Co., Ltd.Inventors: Susumu Komiyama, Hiroshi Iwano, Musashi Yamaguchi, Hideaki Watanabe
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Patent number: 6994199Abstract: The invention concerns a load torque lock for automatically locking load-side torques in the case of a decrease or cessation of a drive-side torque having a housing (11) fixed to a frame, a locking ring (17) permanently connected to it and a locking body (17) cooperating with it and revolving on the drive side, with locking devices which, on the one hand, clamp on the locking ring (17) with the occurrence of a load torque by swiveling the locking body (17) by means of locking elements (27, 28) of the output shaft (15) and, on the other hand, release from the locking ring (17) by swiveling the locking body (17) back by means of driving elements (23, 24) of the drive shaft (14). To avoid undesired friction or defective jamming of the locking devices on the locking ring (18) by the centrifugal forces of the locking body (17) it is embodied in such a way that its mass center of gravity (M) lies in the area of the rotational axis of the drive shaft and the output shaft that are aligned with one another.Type: GrantFiled: September 20, 2002Date of Patent: February 7, 2006Assignee: Robert Bosch GmbHInventors: Ingo Drewe, Guido Schneider
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Patent number: 6967450Abstract: Enhancements for moving displays in general, and in particular, dynamic signage and kinetic sculpture. More specifically, the present invention relates to improvements on moving banners (18) for use within entertainment, advertising, signage, art, theater, performance visual instruments, and attraction contexts. Improvements are cost-saving computer controlled torque friction brakes (16), substantially inelastic reinforcing cable (20) to allow elastic banners (18) to handle relatively higher wind loads, and reusable removable printed image banner sleeves (22).Type: GrantFiled: May 13, 2003Date of Patent: November 22, 2005Inventor: David Milton Durlach
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Patent number: 6831432Abstract: Brake mode switching signal production means detects the number of revolutions per unit time of a rotor according to a change in a positional relationship between motor windings of a plurality of phases and the rotor so as to output first and second brake mode switching signals for selecting either a short brake mode or a reverse brake mode for braking the rotation of the rotor based on the number of revolutions. Control means outputs an energization control signal for controlling energization of the motor windings of a plurality of phases in response to the first and second brake mode switching signals. Thus, it is possible to reduce the braking noise and the stopping time.Type: GrantFiled: December 3, 2002Date of Patent: December 14, 2004Assignee: Matsushita Electric Industrial Co., Ltd.Inventor: Maki Murakami
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Publication number: 20040239196Abstract: The present invention provides a motor with a brake in which, after an initial stage, a voltage applied to the brake is reduced to thereby restrain heat generation in the brake. In the motor with a brake, after signal drive, a voltage of a drive signal supplied to an electromagnetic drive portion of the brake is reduced, whereby heat generation in the brake during motor rotation is restrained, which makes it possible to increase a load to be applied to the motor.Type: ApplicationFiled: March 1, 2004Publication date: December 2, 2004Inventors: Hiromasa Miura, Toshiyuki Noda
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Patent number: 6774595Abstract: The invention concerns a device and a method for monitoring an electromechanical brake-applying device designed for motor vehicle brakes. Said electromechanical brake-applying device comprises the following elements: a control member comprising an electric motor provided with electric supply; preferably a cylinder with accumulator including a spring which can be tensioned by the control member and serving to actuate a plunger to apply and release the vehicle brake. The monitoring device has a detecting unit for establishing an intensity and/or voltage curve of the current flowing in the electric supply whereof the output is connected to an evaluating unit for comparing the value of said intensity and/or voltage curve with previously stored threshold values and/or previously stored threshold value characteristic.Type: GrantFiled: July 1, 2002Date of Patent: August 10, 2004Assignee: Knorr-Bremse Systeme fuer Nutzfahrzeuge GmbHInventors: Thomas Laxhuber, Hans Baumgartner, Wolfgang Pahle
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Publication number: 20040145328Abstract: 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 armature short-circuit brake and the mechanical brake, and the armature short-circuit brake is switched off when reaching a thermal load limit for the electric motor or the control electronics.Type: ApplicationFiled: November 21, 2003Publication date: July 29, 2004Applicant: SIEMENS AKTIENGESELLSCHAFTInventor: Ronald Hauf
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Patent number: 6731084Abstract: The present method and system allows minimization of a rollback effect when an electric vehicle, such as a wheelchair, brakes on a slope. The system comprises secondary brake, a controller, and a monitor that allows to apply both a control voltage and the secondary brakes according to an appropriate sequence to provide stops and starts with a minimized rollback effect. An updated armature resistance value is advantageously used to take into account evolutive conditions of the vehicle.Type: GrantFiled: October 15, 2002Date of Patent: May 4, 2004Assignee: Liber-T Medtech Inc.Inventors: Eric Gagnon, Thomas Cliche
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Patent number: 6687593Abstract: A combined regenerative and friction braking system for the road wheels of a vehicle includes a friction braking subsystem, a regenerative braking subsystem coupled to the road wheels equipped with the friction braking subsystem, and a brake system controller for controlling both the friction and regenerative braking subsystems such that regenerative braking is restored to a maximum practicable value following conclusion of an antilock braking event.Type: GrantFiled: September 6, 2002Date of Patent: February 3, 2004Assignee: Ford Motor CompanyInventors: Dale Scott Crombez, Steven Lee Napier
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Patent number: 6633146Abstract: A braking device for an electrical tool and including an actuation member (1), a braking drum (4) secured on the shaft of the electrical tool for joint rotation therewith, and a braking member (5) secured on the actuation member for joint displacement therewith, the actuation member being linearly displaceable upon a biasing force of a return spring acting thereon for pressing the braking member against a circumferential surface of the braking drum for braking the shaft and thereby the working tool.Type: GrantFiled: August 13, 2001Date of Patent: October 14, 2003Assignee: Hilti AktiengesellschaftInventors: Markus Hartmann, Günter Haas, Andreas Dieterle
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Publication number: 20030117096Abstract: The present method and system allows minimization of a rollback effect when an electric vehicle, such as a wheelchair, brakes on a slope. The system comprises secondary brake, a controller, and a monitor that allows to apply both a control voltage and the secondary brakes according to an appropriate sequence to provide stops and starts with a minimized rollback effect. An updated armature resistance value is advantageously used to take into account evolutive conditions of the vehicle.Type: ApplicationFiled: October 15, 2002Publication date: June 26, 2003Applicant: Liber-T Medtech Inc.Inventors: Eric Gagnon, Thomas Cliche
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Patent number: 6531839Abstract: 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 of energy exhaustion, and when the rotation speed of the motor reduces below a predetermined speed, the present invention stops the motor using an electrical brake method. Therefore, since the mechanical brake method is used during the high speed rotation interval, heat occurrence can be prevented, and the electrical brake method is used during the relatively low speed interval so that the motor can be stopped within a short time.Type: GrantFiled: March 22, 2000Date of Patent: March 11, 2003Assignee: Fairchild Korea Semiconductor Ltd.Inventors: Yong-Sang Shin, Dong-Gyu Kim, Sung-Jun Joo
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Patent number: 6498448Abstract: A motor brake releasing device includes an electromagnetic brake for locking a motor shaft and a switch mounted between the electromagnetic brake and a releasing-power-supply for the brake. The switch can be operated by an AND signal produced by a motor driving signal and a motor-brake-release-permitting signal. This structure allows a motor brake to be released when a motor driving system encounters an obstacle, although the motor is left free. The structure also can prevent a final object of the motor shaft from dropping due to its own weight.Type: GrantFiled: June 1, 2001Date of Patent: December 24, 2002Assignee: Matsushita Electric Industrial Co., Ltd.Inventor: Shigeru Shimogama
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Patent number: 6452350Abstract: A linear drive to drive an article of furniture includes at least one drive motor that is coupled with a linearly moveable driven member and a braking system with a controlled braking element which commences the braking function without delay. The braking system can have a small footprint. According to the invention, the drive for the article of furniture can include an actuator, such as a piezo actuator coupled directly or indirectly with the braking element acting on the rotor shaft of the drive motor. The piezo actuator is preferably connected to the electric terminals of the drive motor. The linear drive can be used to adjust the support for a lath bed or a chair.Type: GrantFiled: October 16, 2000Date of Patent: September 17, 2002Assignee: Dewert Antriebs- und Systemtechnik GmbH & Co. KGInventors: Horst Finkemeyer, Fried-Helm Herzig, Ralf Bokämper
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Patent number: 6441573Abstract: A blended electrical/friction braking system includes an electric brake feedback monitor which monitors a first signal corresponding to an electric brake effort request of an electric motor of an electrically powered vehicle. The electric brake feedback monitor detects one or more electrical conditions of the electric motor during electric braking and selectively supplies/terminates the first signal to/from a brake controller as a function of the first signal and the one or more electrical conditions. In response to termination of the first signal thereat, the brake controller causes a friction brake of the vehicle to assume the entire braking effort of the vehicle.Type: GrantFiled: April 28, 2000Date of Patent: August 27, 2002Assignee: DaimlerCrysler AGInventors: Pierre A. Zuber, Richard P. Ames, Nikola V. Langovsky, William E. Madden, Jr., Steven T H Chang, Robert W. Phillips, Theresa A. Barbour
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Patent number: 6333611Abstract: A motor drive apparatus is provided in an injection molding machine in order to supply electrical energy to a motor. The motor drive apparatus includes an electricity accumulation unit for accumulating electrical energy; and an electricity accumulation circuit for accumulating in the electricity accumulation unit electrical energy regenerated from the motor during a deceleration period of the motor and for supplying the electrical energy accumulated in the electricity accumulation unit to the motor during an acceleration period of the motor.Type: GrantFiled: November 5, 1999Date of Patent: December 25, 2001Assignees: Nisso Electric Company, Nissei Plastic Industrial CO, Ltd.Inventors: Hiroshi Shibuya, Satoshi Nishida, Atsushi Koide, Hiroshi Yamaura
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Patent number: 6294887Abstract: 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 secures space saving and high safety, and is economical.Type: GrantFiled: April 14, 2000Date of Patent: September 25, 2001Assignee: Matsushita Electric Industrial Co. Ltd.Inventors: Shigeru Shimogama, Yasumichi Muto
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Patent number: 6160368Abstract: A disk drive includes a spindle motor having windings and a spindle motor driver including switching elements connected to the windings. Spin-down instructions are stored in a memory. A microprocessor is responsive to a spin-down command to receive and execute the spin-down instructions. The execution of the spin-down instructions causes the microprocessor to perform the following pulsed braking sequence: (1) providing a brake signal for a first selected period of time (T1); (2) providing a coast signal for a second selected time period (T2); and (3) repeating (1) and (2). The spindle motor driver is responsive to the coast signal to control the switching elements to cause the spindle motor to coast and is responsive to the brake signal to control the switching elements to brake the spindle motor.Type: GrantFiled: June 22, 1998Date of Patent: December 12, 2000Assignee: Western Digital CorporationInventor: Eugene F. Plutowski
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Patent number: 6097165Abstract: 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 actuates the motor to operate in zero servo mode and maintain the load. An alarm is also sounded, allowing an operator to safely lower the load.Type: GrantFiled: August 3, 1998Date of Patent: August 1, 2000Assignee: Ace-TronicsInventor: Bradley Vinson Herron
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Patent number: 5962998Abstract: A circuit for initiating the setting of a series brake upon detecting a loss of armature current in an overhauling DC crane motor. The circuit includes an ammeter shunt, a meter relay and associated contact, a meter relay power supply, a control relay and associated contact, a low current relay and associated contact and two static timers which can be added to an existing crane operating circuit. The ammeter shunt is located electrically in series with motor armature for monitoring current flow in the armature. The meter relay is connected to the ammeter shunt such that it will operate in response to a signal from the ammeter shunt indicating that current in the motor armature has dropped below a predetermined level. The meter relay requires power for operation, this power being provided by the 24 VDC power supply.Type: GrantFiled: December 29, 1998Date of Patent: October 5, 1999Assignee: Square D CompanyInventors: Patrick J. Bowers, Joseph M. Palma
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Patent number: 5782322Abstract: The invention is directed to a brake actuator (2) having a transmission including an electric motor (6) as a drive element, a converting device for converting the rotational movement of the electric motor (6) into a linear movement and a hydraulic transmission (16, 18, 20) for transmitting the linear movement of the converting device to a friction lining (22) of a brake. The brake actuator of the invention does not require a mechanical transmission connected between the motor and the hydraulic transmission. This is achieved with a converting device configured as a spindle unit (12, 14) and is realized in that the spindle nut (12) is fixedly connected to the electric motor (6) and the spindle rod (14) is fixedly connected to a first hydraulic piston (16) of the hydraulic transmission (16, 18, 20). The electric motor is provided with a hollow shaft (10) for accommodating the displacement stroke of the spindle rod.Type: GrantFiled: May 24, 1996Date of Patent: July 21, 1998Assignee: Continental AktiengesellschaftInventors: Stefan Hauck, Thomas Dieckmann, Christof Maron, Friedhelm Bergmann
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Patent number: 5621295Abstract: Device for driving a body by means of an electric motor, comprising mechanical means for measuring the displacement of said body which are kinematically linked to the body and are equipped with switches (ID, IM) actuated by the mechanical measurement means at certain points on the trajectory of the body. The device comprises means for initializing a phase for specific powering of the motor such as power supply at reduced torque for a timed duration (TP, x, C4) or power supply at reduced voltage or cut-off of the power supply, switched in by actuation of at least one of said switches.Type: GrantFiled: February 8, 1995Date of Patent: April 15, 1997Assignee: SOMFYInventors: Christian Vanderschaeghe, Serge Bruno
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Patent number: 5530328Abstract: 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 other locomotive consist power monitors, either through the MU cable or over a wireless link, to display consist status to the engineer. Where the communication is through the MU cable, the communications link is provided by a high frequency carrier superimposed on an existing MU cable wire. No modification is required to the MU cable allowing for easy retrofit of existing locomotives. The alternative wireless communication is accomplished by means of a low power, spread spectrum data link now being incorporated into new locomotives. Information exchanged among the consist power monitors pertains to loading and dynamic brake conditions of the locomotives in the consist. Locomotive consist information is presented continuously.Type: GrantFiled: December 23, 1993Date of Patent: June 25, 1996Assignee: Pulse Electronics, Inc.Inventors: Emilio A. Fernandez, Angel P. Bezos
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Patent number: 5406180Abstract: The present invention provides an internal braking system for use with electric motors, particularly electric motors used with rotary actuators. The braking system includes a brake which has a spindle disposed at least partially between the rotor and a shaft. An annular engagement portion of the brake is integrally connected to the spindle through a conical portion. The brake is forced against a stationary friction member when the motor is de-energized. The brake is preferably made from a polymeric alloy having self-lubrication properties.Type: GrantFiled: January 26, 1994Date of Patent: April 11, 1995Assignee: Johnson Service CompanyInventor: Raymond D. Feller, Jr.
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Patent number: 5324106Abstract: A drive motor comprises a motor body (5) for rotating a motor shaft (11) in a predetermined forward direction; a brake engagement surface (30) formed at a projection (14) which is projected from a part of the motor shaft; claw piece (15) which engages with the projection at a predetermined position on interruption of electricity for the motor body and acts to stop rotation of the motor shaft, wherein the claw piece comprises an engagement claw (60) of actue angle shape; and a wedge engagement release mechanism (31) for releasing the wedged engagement by rotating the motor shaft in a release direction which is equal to the reversed direction.Type: GrantFiled: July 2, 1992Date of Patent: June 28, 1994Assignee: Asahi Seiko Kabushiki KaishaInventors: Hiroshi Abe, Yorio Suzukawa
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Patent number: 5306989Abstract: The present invention provides an internal braking system for use with electric motors, particularly electric motors used with rotary actuators. The braking system includes a brake which has a spindle disposed at least partially between the rotor and a shaft. An annular engagement portion of the brake is integrally connected to the spindle through a conical portion. The brake is forced against a stationary friction member when the motor is de-energized. The brake is preferably made from a polymeric alloy having self-lubrication properties.Type: GrantFiled: May 27, 1992Date of Patent: April 26, 1994Assignee: Johnson Service CompanyInventor: Raymond D. Feller, Jr.
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Patent number: 5157307Abstract: A sewing machine drive apparatus having a first and second rectifying circuit connected to an AC power source, and a sewing machine control circuit for outputting a drive signal and for outputting a voltage control signal after a certain time period has elapsed from outputting said drive signal. A motor drive circuit is connected to the first rectifying circuit for driving a motor. A DC/DC converter solenoid power source circuit is connected to the second rectifying circuit for outputting a rated voltage of a solenoid, and for outputting a hold voltage to hold the solenoid in response to a voltage control signal. A solenoid drive circuit inputs the output of the DC/DC converter solenoid power circuit in response to a drive signal to drive the solenoid.Type: GrantFiled: February 22, 1990Date of Patent: October 20, 1992Assignee: Matsushita Electric Industrial Co., Ltd.Inventor: Hiromitsu Noda
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Patent number: 5050711Abstract: A stationary brake member (45) which is used in an electromagnetic brake apparatus, comprises a first press-worked plate (45h) and a second press-worked plate (45m) which are laminated to each other. The second press-worked plate (45m) has plural hooks (45q), (45s) to grip the first press-worked plate (45h). The first press-worked plate (45h) has plural projections (45k) with spaces (45t) therebetween, and the projections are buried in the cast bracket (31), whereby the first press-worked plate (45h) is firmly fixed to the bracket (31).Type: GrantFiled: March 15, 1990Date of Patent: September 24, 1991Assignee: Mitsubishi Denki Kabushiki KaishaInventor: Tatsuya Sawato
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Patent number: 4995488Abstract: A servo control device comprises a motor and continuously acting friction device, which is coupled to the output shaft of the motor and arranged in a housing having an aperture through which the motor output shaft extends. The housing is mounted so as to float radially in a mounting which is provided for it in a casing. Resilient tongues are provided so as to act between the housing and the mounting. The invention is particularly applicable to the motorized servo control of a clutch.Type: GrantFiled: January 16, 1990Date of Patent: February 26, 1991Assignee: ValeoInventors: Patrice Bertin, Yvon Sevennec
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Patent number: 4975627Abstract: In an elevator, an electric motor is connected to a brake through a gearbox. The brake is controlled with an electromagnet. A torque signal is applied to the motor. Brake voltage characteristics are used to detect actual brake engagement and to signal a switch to substitute a decaying torque control signal to the motor for the motor torque signal supplied to the motor while the elevator is moving. Motor torque is thereby gradually rather than suddenly reduced to zero.Type: GrantFiled: August 15, 1988Date of Patent: December 4, 1990Assignee: Otis Elevator CompanyInventor: Narasimha K. Reddy
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Patent number: 4965497Abstract: A control circuit for an electric motor having a power control element containing a first semiconductor for driving the motor in one torque direction, and a power control element containing a second semiconductor for driving the motor in the other torque direction includes a circuit-breaker for at least isolating one of the power control elements, upon failure of the one power control element, and connecting the remainder of the circuit to the other power control element instead of the failed power control element.Type: GrantFiled: April 29, 1988Date of Patent: October 23, 1990Assignee: Heidelberger Druckmaschinen AGInventors: Anton Rodi, Michael Kruger
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Patent number: 4827204Abstract: In an electric motor with a damping device incorporating a disc-shaped damping mass which is freely rotatable and axially movable in relation to the driven element and consists at least partially of a mangetizable material, the damping mass is located within the range of a stray magnetic field (31) of the motor (11) and is pressed against a friction plate (28) located between the rotor (14) of the motor and the damping mass and rotating with the driven element as a result of the magnetic force of the stray field acting upon the mass.Type: GrantFiled: November 7, 1984Date of Patent: May 2, 1989Assignee: U.S. Philips CorporationInventors: Romuald L. Bukoschek, Hugo Schemmann
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Patent number: 4802558Abstract: Apparatus for protecting the ball screw drive and other agencies involved in the operation of a movable slide of a machine tool from becoming contaminated by cutting fluids, mist, metal dust, chips, etc. An encasement provides a substantially closed chamber for the ball screw and nut. The apparatus also protects the drive from mechanical damage by stopping the rotational inertia of the ball screw when excessive resistance to motion is encountered.Type: GrantFiled: October 1, 1987Date of Patent: February 7, 1989Assignee: The Olofsson CorporationInventor: Donald W. Garnett
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Patent number: 4798269Abstract: A brake mechanism is disclosed wherein a support lever is pivoted at a pivot end to a stationary bearing plate and is urged by a plurality of springs, which engage the support lever radially inwardly from its pivot end, toward the end plate to effect clamping of a rotatable friction disc between the end plate and a brake shoe disposed near the pivot end of the support lever. A solenoid has a plunger pivotally connected directly to a bracket end of the support lever adapted to overcome the forces applied by the springs and release the brake when the solenoid is energized. The springs apply pressure in close proximity to the pivot point and with the solenoid being disposed at the remote free end of the support lever, there are achieved greater mechanical advantages without the need for complicated linkage assemblies. The arrangement of parts is such that the solenoid mechanical advantage is substantially 7 to 1, while the spring-set mechanical advantage is approximately 7 1/2 to 1.Type: GrantFiled: August 6, 1986Date of Patent: January 17, 1989Assignee: PT Components, Inc.Inventors: Bernard J. Lindner, Harold Lorenz
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Patent number: 4792734Abstract: A stepless speed change electric chain block includes a DC motor for driving a load sheave. The chain block comprises a phase control circuit having a variable resistor, a capacitor, a two-way trigger diode, and a triode AC switch for receiving alternating current from alternating power source to control it in phase, a full-wave-rectifier for receiving alternating current controlled in phase in the phase control circuit to convert it into direct current which is supplied into the DC motor, and mechanical brake means provided in a transmission between the DC motor and the load sheave for braking rotation of the load sheave in a winding-off direction. With this arrangement, as the speed setting for winding operation is effected only by the phase control circuit, so that the constitution of the block is simplified and inexpensive in comparison with the prior art. All the supplied power is effectively utilized for operating the chain block.Type: GrantFiled: May 26, 1987Date of Patent: December 20, 1988Assignee: Kabushiki Kaisha KitoInventor: Hisatsugu Watanabe
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Patent number: 4671577Abstract: A vehicle supported for rolling movement on a track by a first set of wheels driven by an electric motor and a second unpowered set of wheels is provided with an improved braking system. The braking system includes a brake pedal which can be depressed to generate a brake demand signal, a regenerative braking system associated with the electric motor, and a friction braking system attached to the unpowered wheels. Control circuitry which regulates the operation of the two brake systems serves normally to actuate the regenerative braking system in response to the brake demand signal and to actuate the friction braking system only when the brake demand signal exceeds a predetermined level which corresponds normally to the maximum regenerative braking available. Under slippery rail conditions, a detector indicates slippage of the wheels relative to the rails during regenerative braking, and immediately actuates the friction braking system to produce additional braking in proportion to the brake demand signal.Type: GrantFiled: November 21, 1985Date of Patent: June 9, 1987Assignee: Urban Transportation Development Corporation Ltd.Inventor: David H. Woods
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Patent number: 4659970Abstract: Automatic guided vehicles are commonly used in industrial material handling operations. Such vehicles must be accurately docked at predetermined stop locations without the guidance or assistance of human operators. The subject apparatus is used in conjunction with a vehicle having a vehicle drive circuit for controllably propelling the vehicle at a velocity responsive to a velocity command signal. At least one ground engaging wheel is equipped with a vehicle brake for controllably stopping the vehicle in response to a brake actuation signal. A position determining element produces a controlled stop signal in response to the vehicle being positioned a predetermined distance from the desired stop location, and an absolute stop signal in response to the vehicle being positioned at the desired stop location.Type: GrantFiled: August 14, 1986Date of Patent: April 21, 1987Assignee: Caterpillar Industrial Inc.Inventor: Grant C. Melocik
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Patent number: 4649329Abstract: An electric actuator having an electric motor operable to determine the output force generated on an output member by a spring; a drive shaft arranged to be driven by the electric motor and having first and second drive means, a non-rotational but axially movable intermediate member which is threadedly engaged with first driven means arranged to be driven by the first drive means; the spring being located between the intermediate member and the output member and arranged so that axial movement of the intermediate member is transmitted to the output member so long as the latter is free to move and, when the output member is restrained from movement, generates the output force on the output member upon continued operation of the electric motor; a stop carried by the intermediate member and positionally adjustable with respect thereto in the direction in which the intermediate member is axially movable, and second driven means with the second drive means, the first driven means being engageable with the stop toType: GrantFiled: April 18, 1985Date of Patent: March 10, 1987Assignee: Westinghouse Brake and Signal Co.Inventor: David J. Wickham
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Patent number: 4609080Abstract: A spring engaged and magnetically disengaged disc brake for engaging two opposing flat surfaces of a rotating disc such as to decelerate the rotating disc. The brake device includes a frame mounted in a fixed position relative to the rotating disc and a pair of identical brake subassemblies interposed portions of the frame and each of the opposing flat surfaces of the rotating disc. Each of the brake subassemblies includes an electromagnet fixedly interconnected with the frame, an armature interposed the electromagnet and one of the flat surfaces of the rotating disc, a spring interposed the frame and the armature to bias the armature towards the rotating disc when the electromagnet is de-energized, and a brake lining interposed the armature and the rotating disc. The frame may be formed of two magnet bodies fixedly interconnected with each other or of a single U-shaped stamping.Type: GrantFiled: March 5, 1984Date of Patent: September 2, 1986Assignee: Facet Enterprises, Inc.Inventor: Thomas C. Sekella
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Patent number: 4546297Abstract: An electric actuator having an output member movable into and out of a force-exerting position, electric motor means operable both to move the output member to and from its force-exerting position and, when the output member is in that position, to control a spring system to generate a required output force on the output member, and means for withholding the spring system from generating a force on the output member until the output member is determined as being in its force-exerting position.Type: GrantFiled: May 7, 1984Date of Patent: October 8, 1985Assignee: Westinghouse Brake & SignalInventors: Jack Washbourn, Howard F. Cogan
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Patent number: 4546295Abstract: The present invention provides an electric actuator having an output member movable from a first variable position to a second variable position; an electric motor operable to control a spring system to exert an output force on the output member when in its second position; a device for generating an electrical signal when the output member is about to leave the second position as it returns to the first position; and a motor-control electrical circuit which recognizes the generation of the electrical signal and thereafter operates the electric motor to a pre-determined degree to move the output member a corresponding pre-determined distance back to the first position so that there is preserved a substantially constant distance between the first and second positions.Type: GrantFiled: May 7, 1984Date of Patent: October 8, 1985Assignee: Westinghouse Brake & SignalInventors: David J. Wickham, Jack Washbourn, Howard F. Cogan
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Patent number: 4546296Abstract: An electric actuator which comprises an electric motor operable to a varying degree correspondingly to cause a spring to generate on an output member an output force which varies in accordance with the varying degree of operation of the electric motor.Type: GrantFiled: May 7, 1984Date of Patent: October 8, 1985Assignee: Westinghouse Brake & SignalInventors: Jack Washbourn, Howard F. Cogan
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Patent number: 4546298Abstract: An electric actuator having an electric motor operable to determine the output force generated on an output member by a spring system, and an adjustable stop by which can be limited the maximum value of the output force, the position of the adjustable stop being variable in accordance with variation of the required maximum value of the output force to be exerted by the output member.Type: GrantFiled: May 7, 1984Date of Patent: October 8, 1985Assignee: Westinghouse Brake & Signal Co.Inventors: David J. Wickham, Jack Washbourn, Howard F. Cogan
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Patent number: 4532460Abstract: A drivetrain (48) for an electric passenger vehicle (10) includes a battery (40) for energizing a single-phase A.C. traction motor (18) which drives a ground engaging wheel (12) through a multi-speed transaxle (20). The motor is characterized by an external ferrite permanent magnet rotor (26) drivingly engaging an input shaft (32) of the transaxle. The motor is controlled by an inverter circuit (44) and a control circuit (46) which generates switch command signals to reciprocally actuate power transistors (56 and 62) within the inverter circuit as a function of operator demand, rotor position and rotor speed. The control circuit includes a motor positioning circuit (442) which toggles the motor current when the rotor speed falls below a predetermined level to dither the rotor about a park position for a predetermined period. A pre-start rotor positioner (224) is provided to mechanically lock the rotor in its park position to ensure the availability of a high electrical starting torque.Type: GrantFiled: July 12, 1982Date of Patent: July 30, 1985Assignee: Eaton CorporationInventors: Allan R. Gale, Richard Chute
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Patent number: 4532462Abstract: An electric actuator having an electric motor operable to control the output force generated by a spring system of the actuator on an output member of the actuator; measuring means responsive to a characteristic of the spring system which is indicative of the value of the output force; and an electrical circuit by which operation of the electric motor can be initiated and can be terminated when the measuring means detects the characteristic as being indicative of the output force of a required value.Type: GrantFiled: May 7, 1984Date of Patent: July 30, 1985Assignee: Westinghouse Brake & SignalInventors: Jack Washbourn, Howard F. Cogan
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Patent number: 4496890Abstract: Controller for an antenna rotator having a rotatable member on which is mounted an antenna to be rotated to various headings. Switching circuitry selectively energizes a motor in the rotator to rotate the member in either of two, opposite directions. Antenna headings are user selectable and pre-programmable, the controller including control circuitry for accepting pre-programmed headings entered from a keyboard, storing the pre-programmed headings and retrieving headings. Users can select a pre-programmed heading or enter a new heading via the keyboard, the control circuitry controlling the motor switching circuitry to rotate the antenna to the selected heading. Circuitry is also provided to energize a brake solenoid in the rotator to, in the absence of jamming or binding, release the brake.Type: GrantFiled: March 11, 1982Date of Patent: January 29, 1985Assignee: Gerard A. Wurdack & Associates, Inc.Inventors: Gerard A. Wurdack, Gene L. Morgan
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Patent number: 4494058Abstract: A system for rotating a data storage disc in a disc drive and for rapidly bringing the disc to a halt comprises a brushless motor fed with direct current in its windings by a motor drive circuit which current is also fed to a solenoid to hold a spring loaded solenoid arm from pressing a brake against a shaft to brake the disc, the motor control circuit using the current caused by back emf in the windings of the motor to provide motor braking while passing the current through the solenoid which applies the brake when the motor speed falls below a predetermined limit, the solenoid also being employed as a current smoothing choke.Type: GrantFiled: December 21, 1982Date of Patent: January 15, 1985Assignee: Burroughs CorporationInventor: Eugenio Berti
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Patent number: 4390260Abstract: The invention contemplates a precisely adjustable threaded mechanism, as for focus adjustment of an aerial camera lens, wherein inner and outer threaded members are normally in circumferentially continuous radially stressed play-free engagement to the extent of requiring a characteristic maximum torque for their rotary adjustment. One of these members is continuously excitable (with respect to the other) as to so incrementally change its circumferential extent with respect to the circumferential extent of the other of said members that their characteristic engagement torque is reduced from said maximum. And a rotary-drive torque of a level less than said maximum engagement torque but greater than the reduced engagement torque is operative to impart an incremental thread-advancing rotary drive, during such intervals as the engagement torque is thus reduced.Type: GrantFiled: July 27, 1981Date of Patent: June 28, 1983Assignee: Carl Zeiss-StiftungInventor: Reinhard Prinz
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Patent number: RE32610Abstract: An electric actuator which comprises an electric motor operable to a varying degree correspondingly to cause a spring to generate on an output member an output force which varies in accordance with the varying degree of operation of the electric motor.Type: GrantFiled: October 30, 1986Date of Patent: February 23, 1988Assignee: Westinghouse Brake and Signal Co., Ltd.Inventors: Jack Washbourn, Howard F. Cogan