Abstract: A lock assembly is disclosed that includes a base formed from a magnetic flux conducting material, the base secure to a chassis. A pin slidably disposed in the base and configured to move from a first open position to a second closed position. A magnet, disposed on a surface of a riser and configured to create a force on the pin that causes the pin to move from the open position to the closed position when the riser is disposed with the chassis.

Abstract: An abnormality determination system includes motor control circuitry that controls a motor of a motor-driven machine based on a motor control command, and compares operation data of the motor obtained in controlling the motor with reference data stored in a storage to determine whether the motor driven machine has an operation abnormality, upper-level control circuitry that transmits the motor control command to the motor control circuitry, and data transceiver circuitry that transmits and receives the reference data and the operation data to and from the motor control circuitry.

Abstract: Provided is a robot equipped with two joint parts attached to an end of an arm in a coupled state. For example, in a joint part of a robot, a motor and a reduction gear are housed in a case, and an output-side member having a flange is fixed to the output shaft of the reduction gear. An opening that opens in the direction orthogonal to the axial direction of the output shaft of the reduction gear is formed in the case. A planar attachment face orthogonal to the opening direction of the opening is formed in the opening. The robot is provided with a plurality of biaxial joint units comprising two joint parts. In the robot, the attachment face of the case of one joint part constituting a biaxial joint unit is fixed to the flange of the other joint part either directly or via a coupling member.

Abstract: A system and method having a magnetic brake apparatus configured to be operable for slowing or stopping motion with magnetic or electromagnetic force. An electromagnetic coil appliance generates the magnetic or electromagnetic force when power is applied to the electromagnetic coil appliance. A brake control module is configured to be operable for controlling the magnetic brake apparatus. A controller implement of the brake control module is configured to be operable for processing a program instruction to control an operation of the magnetic brake apparatus where a full-bridge driver coupled to the controller implement, applies power the electromagnetic coil appliance. A receiver device is configured to supply a control signal to the controller implement.

Abstract: Improved maneuverability, improved followability towards a target braking force and enhanced brake feeling when a low braking force is being effected may be achieved. A brake controller unit may include a clearance estimator which may be configured to use a rotational angle ? of a motor to estimate a clearance, inclusive of negative values, between a frictional material and a brake. A target braking force Fr may be compared with a switch-determining braking force Frsw, so that clearance control based on a target clearance Cr may be performed when the frictional material is in approximate-contact state corresponding to the target braking force Fr being low, and so that braking force control may be performed when it is equal to or greater than the switch-determining braking force Frsw.

Abstract: A control device for a switching device with separate start-up and holding coils includes control electronics to control the current supply to the start-up and holding coils and a direct voltage supply unit for the holding coil and the control electronics with the same reference potential for the holding coil and the control electronics.

Abstract: A haptically-enabled system includes an actuator that has a first terminal and a second terminal. The second terminal is coupled to a voltage source, and a first switch is coupled to the first terminal and to ground. A second switch is coupled to the actuator. The second switch is parallel to the actuator.

Abstract: Provided is a hybrid construction machine capable of letting the operator immediately stop the swing structure by performing a stopping operation for ordinary construction machines even when the swing structure moves differently from the operator's will for some reason. The hybrid construction machine comprises: an inverter controller which outputs a PWM signal to an inverter and thereby controls the revolution speed of an electric motor; a first electric circuit including blocking means which blocks the PWM signal outputted from the inverter controller to the inverter in response to either an immobilization selection inputted through a gate lock lever switch or an OFF selection inputted through an ignition switch; and a second electric circuit including a swing brake solenoid valve which activates a swing brake in response to either the immobilization selection inputted through the gate lock lever switch or the OFF selection inputted through the ignition switch.

Abstract: An electric motor controller includes controller electronics configured to control an electric motor. The electric motor controller also includes a thermoelectric cooler in thermal communication with the controller electronics. The thermoelectric cooler is configured to receive a braking current associated with braking of the electric motor and provide cooling to the controller electronics.

Abstract: A frequency converter and a method for determining the position of the rotor of an electric machine are provided. The frequency converter includes a load bridge and a control of the load bridge, for supplying electricity between the load bridge and an electric machine connected to the load bridge. The frequency converter includes a determination for at least one electrical parameter of the electric machine, and includes a determination for the position of the rotor of the electric machine. The load bridge is fitted to supply a first alternating electricity excitation signal, which is formed in relation to the electrical angle of the electric machine, to the electric machine. The frequency converter is further fitted to determine the first alternating electricity response signal corresponding to the first alternating electricity excitation signal, and the position of the rotor is determined on the basis of the first alternating electricity response signal.

Abstract: The invention relates to a braking apparatus, an electric drive and an elevator system. The braking apparatus comprises an apparatus for dynamic braking, for braking an electric machine with dynamic braking, an input for the control signal of the braking apparatus, and also a controller, for controlling the apparatus for dynamic braking as a response to the aforementioned control signal of the braking apparatus.

Abstract: An electro-mechanical linear actuator unit comprising an actuator housing that accommodates at least two electric drives, each of which, when actuated by a control device, sets an associated drive of a respective spindle drive into rotation for adjusting linear movement of the associated spindle drive in order to produce relative linear adjustment of a control rod. The two electric drives are located in the actuator housing in such manner that relative adjustment can be produced by simultaneous actuation of the two electric drives, as the sum of the adjustment movements of the associated spindle drives, or by actuating a single electric drive, as the adjustment movement of the associated spindle drive. A respective brake is provided, in an area of each of the two electric drives, which can be selectively actuated by the control device to then prevent the adjustment movement of the respective associated spindle drive.

Abstract: A process for electrical assistance to the braking of a vehicle with a motor system (M), whereby the motor system (M) includes at least one electric motor (10) whose output shaft (14) is coupled to a primary shaft (20) that drives at least one wheel (22) of the vehicle, at least one wheel (22) of the vehicle being equipped with a mechanical braking device that is activated by a hydraulic circuit, whereby the process is characterized in that it includes: collecting information in the hydraulic circuit of the primary braking circuit, and using the information as a set-point for a braking torque generated by the electric motor (10) and exerted on the primary drive shaft (20) of the wheels.

Abstract: An electric motor drive system capture and control apparatus for energy savings has an alternating current power source electrically connected to a direct current motor. A power rectifier diode rated for the alternating current power source and the direct current motor is electrically connected in a reverse bias mode between the negative supply wire of the direct current motor and a grounded neutral conductor of the alternating current power source. A ground wire is electrically connected to the direct current motor and cross connected to a hot lag wire of the alternating current power source. The direct current motor is voltage matched to the alternating current power source. A transformer is electrically connected to the alternating current power source and the direct current motor. The system may be scaled to work with a power grid or for use in a vehicle.

Abstract: An actuator comprising at least one multiphase motor having phases facing a rotor secured to an outlet shaft associated with a braking member and provided with a connection to a movable element that is to be moved, the motors and the braking member being connected to at least one motor control unit for controlling the motors by powering their phases. The motor has at least four phases wound in such a manner as to avoid a neutral point, and in that the control unit has one single-phase inverter per phase and is arranged to implement a nominal, three-phase mode of control, and a degraded mode of control that enables the rotor to be driven in rotation by powering two non-collinear phases thereof.

Abstract: A drive unit for operating a device, in particular a device in a vehicle and a method for operating a drive unit are provided. An electrical drive assembly and a break assembly are combined and arranged together in a common housing. The breaking assembly could be a mechanical breaking assembly or an electrical break assembly. The break assembly automatically locks the shaft of the electrical drive assembly and thus provides self-locking capabilities.

Abstract: A control system for controlling an electrical device of a nacelle, the device having at least one element that is movable to a closed position and an open position. The control system includes at least one electromechanical member for actuating the movable element, a unit for electrically driving the electromechanical actuation member, and a controlling and monitoring unit for controlling the electrical drive unit so as to move the movable element to the closed and/or open position. The control system further includes a system for recovering braking power from the electrical drive unit during the movement of the movable element to the closed and/or open position.

Abstract: A system and method for determining the holding torque of a brake in a material handling system is disclosed. The material handling system may include a bridge, a trolley, and a hoist, each driven along a different axis by a motor. A brake is operatively coupled to the motor to prevent unwanted motion of the motor. A motor controller is coupled to each motor which controls operation of the motor and its corresponding brake. The motor controller generates a torque command to the motor while keeping the brake set. The initial torque command is less than the holding torque of the brake. The torque command is incremented until motion is detected on the motor. The torque value when motion is detected is stored in the motor controller and displayed to an operator.

Abstract: An electric brake system for an electromechanical machine connected to output terminals of an inverter, input terminals of which are supplied by a DC voltage source. The system includes an electrical circuit connected between the input terminals of the inverter and including, connected in series: a mechanism dissipating electrical energy returned by the electromechanical machine to the input terminals of the inverter during a braking phase of the electromechanical machine, including an inductor wound around a magnetic circuit; and a switching mechanism to close the electrical circuit during a braking phase of the electromechanical machine and to open the electrical circuit in absence of a braking phase of the electromechanical machine.

Abstract: A system and method for determining the holding torque of a brake in a material handling system is disclosed. The material handling system may include a bridge, a trolley, and a hoist, each driven along a different axis by a motor. A brake is operatively coupled to the motor to prevent unwanted motion of the motor. A motor controller is coupled to each motor which controls operation of the motor and its corresponding brake. The motor controller generates a torque command to the motor while keeping the brake set. The initial torque command is less than the holding torque of the brake. The torque command is incremented until motion is detected on the motor. The torque value when motion is detected is stored in the motor controller and displayed to an operator.

Abstract: An electric brake device is provided for electronically controlled synchronous motors which are supplied with voltage by way of a converter. The synchronous motor contains a winding center point and that the winding center point is connected by way of an electric resistor and a switch to a ground point of the converter and that the phases of the converter that are connected to the ground point contain in each case a free-wheeling diode.

Abstract: A programmable robot system includes a robot provided with a number of individual arm sections, where adjacent sections are interconnected by a joint. The system furthermore includes a controllable drive mechanism provided in at least some of the joints and a control system for controlling the drive. The robot system is furthermore provided with user a interface mechanism including a mechanism for programming the robot system, the user interface mechanism being either provided externally to the robot, as an integral part of the robot or as a combination hereof, and a storage mechanism co-operating with the user interface mechanism and the control system for storing information related to the movement and further operations of the robot and optionally for storing information relating to the surroundings.

Abstract: There is provided a slewing control device that enables to detect breakdown of a driving system of a mechanical brake, and generate a torque for holding a slewing body in a stopped state to thereby prevent movement of the slewing body when an anomaly has occurred. In a working machine for driving a slewing body by an electric motor 1, judgment is made as to whether a mechanical brake 4 is in an inconsistent state, based on a command to be outputted to a brake circuit B, and a pressure detected by a brake pressure sensor 17. The inconsistent state is a state that the mechanical brake 4 is in a brake released state when an activation command for switching the mechanical brake 4 to a brake activated state is outputted. If it is judged that the mechanical brake 4 is in the inconsistent state, a command for obtaining a braking torque for holding the slewing body in a stopped state is outputted to the electric motor 1.

Abstract: A frequency converter and a method for determining the position of the rotor of an electric machine are provided. The frequency converter includes a load bridge and a control of the load bridge, for supplying electricity between the load bridge and an electric machine connected to the load bridge. The frequency converter includes a determination for at least one electrical parameter of the electric machine, and includes a determination for the position of the rotor of the electric machine. The load bridge is fitted to supply a first alternating electricity excitation signal, which is formed in relation to the electrical angle of the electric machine, to the electric machine. The frequency converter is further fitted to determine the first alternating electricity response signal corresponding to the first alternating electricity excitation signal, and the position of the rotor is determined on the basis of the first alternating electricity response signal.

Abstract: A brushless generator with permanent-magnet multi-pole rotor disks and stator winding disks in their axial magnetic field includes integral electronics to efficiently generate regulated DC current and voltage from mechanical input power over a broad speed range. All power for the electronics is provided by rectifier diodes from its stator windings. Differential amplifiers provide stator voltage feedback signals. Its power rating is scalable, depending on the number of its disks. Having no iron cores and no gears, it incurs no cogging torque, and no gear friction. Integral power control electronics includes high-frequency pulse-width-modulated boost regulation, which provides regulated current at requisite voltage over its broad speed range. A main wind-powered embodiment to produce DC power for a constant voltage DC load over a broad speed range includes signal processing so output power varies according to the third power of speed.

Abstract: An electronic drive includes an electro-mechanical brake associated with a direct-current motor. A first valve or diode connects one of the terminals of the direct-current motor with the first electrical terminal of the brake in a forward direction. A second valve or diode connects the other terminal of the direct-current motor with the first electrical terminal of the brake. A second electrical terminal of the brake is at least indirectly connected with a reference voltage.

Abstract: In a parking brake control device, the minimum value of a motor current is set as an idle current after a motor begins to be driven, specifically, in a period during which the idle current is being sampled. As a result, the idle current is set to a value which reflects the temperature of an electric parking brake and the dispersion of individual units of the motor. Accordingly, it is possible to provide a parking brake control device, which can set a target current value capable of coping with the dispersion of the individual units of the motor by calculating the target current value by adding a target effective current necessary to generate an actuation force to the idle current set as described above.

Abstract: 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 and releases when the electromagnet is energized. When applied the permanent magnet moves the brake pad into frictional engagement with a housing, and when released the electromagnet cancels the flux of the permanent magnet to allow a leaf spring to move the brake pad away from the housing. A controller has a DC/DC converter for converting a main bus voltage to a lower braking voltage based on certain parameters. The converter utilizes pulse-width modulation (PWM) to regulate the braking voltage. A calibrated gap is defined between the brake pad and permanent magnet when the brake assembly is released, and may be dynamically modified via the controller.

Abstract: A motor drive includes a dynamic braking circuit for producing a deceleration torque utilizing a braking force caused by a synchronous motor acting as a generator when the synchronous motor is deenergized. The motor drive apparatus is equipped with a dynamic braking circuit fault detection capability, a DC power supply which is obtained by rectifying input AC power, voltage application function for applying a voltage to the windings of the synchronous motor and to the dynamic braking circuit for a predetermined length of time by switching power transistors connected to the DC power supply, current detection unit for detecting the value of a current flowing from the power transistors, and fault checking unit for checking the dynamic braking circuit for the presence or absence of a fault, based on the current value detected by the current detection unit and on a predefined threshold value.

Abstract: An electrically-driven dump truck 1 uses resistors to convert electric power generated during retarder braking operation into heat energy. A body frame 2 has front and rear wheels, a support base 2A, a cab 4 mounted on an upper left surface of the support base, and a control cabinet 3 mounted on an upper surface of the support base. A plurality of resistor boxes 5 are mounted on an upper base plate 2B and are arranged in a stacked manner such that the plurality of resistor boxes 5 are located to the right of the control cabinet 3 in order to secure right side visibility from the cab 4. Each resistor box has a casing with plural resistors connected in parallel, an inlet port and an outlet port. A fan for cooling the resistors is housed in the casing.

Abstract: The present invention advantageously provides methods for manually and/or remotely controlling a motorized roller shade that includes a shade attached to a shade tube, a DC gear motor disposed within the shade tube and a microcontroller. One method includes detecting a manual movement of the shade using a sensor, determining a displacement associated with the manual movement, and, if the displacement is less than a maximum displacement, moving the shade to a different position by energizing the DC gear motor to rotate the shade tube. Another method includes receiving a command from a remote control, and moving the shade to a position associated with the command by energizing the DC gear motor to rotate the shade tube.

Abstract: A servomotor system is provided. The servomotor system includes an enclosure and a motor stator and rotor disposed in the enclosure. The servomotor system also includes a motor brake disposed in the enclosure and configured to selectively brake the rotor from rotation and a brake control switch disposed in the enclosure and coupled to the motor brake for selectively providing power to the motor brake for selectively engaging and/or disengaging the brake.

Abstract: A method for braking an electric utility vehicle including a motor and an electromechanical brake. The method includes storing a value indicative of at least one of an amount of current, voltage, and power that is commanded to a motor of the electric utility vehicle to maintain the electric utility vehicle in a stopped state; engaging a parking brake function of an electromechanical brake after the storing; disabling the motor after the engaging; commanding the at least one of the current, voltage, and power to the motor at the stored value when an accelerator pedal is depressed; and disengaging the parking brake function after the commanding.

Abstract: The invention relates to a frequency converter, and also to a method for determining the position of the rotor of an electric machine. The frequency converter comprises a load bridge and also a control of the load bridge, for supplying electricity between the load bridge and an electric machine connected to the load bridge. The frequency converter comprises a determination for at least one electrical parameter of the aforementioned electric machine, and the frequency converter comprises a determination for the position of the rotor of the aforementioned electric machine. The load bridge is fitted to supply a first alternating electricity excitation signal, which is formed in relation to the electrical angle of the electric machine, to the aforementioned electric machine.

Abstract: The start timing of the pole position inference process of the linear motor installed vertically is delayed by a predetermined time after instruction of brake release. For example, from (1) increasing of the thrust instruction value of an ASR control system up to a predetermined value, (2) the movement (falling) distance of the moving part, or (3) the moving (falling) speed of the moving part, the release condition of the brake is detected and moreover after a predetermined time, the inference process of the pole position is started. The inference process of the pole position of a synchronous motor is fit to the release timing of a brake and a malfunction of the inference process and a runaway (falling in the vertical drive) of a moving part are prevented.

Abstract: In an excavator equipped with an offset boom, an offset command value generating device of a rotation control device offsets a second boom arranged on a distal end side in a rotation direction relative to a first boom arranged on a proximal end side when an acceleration start judging device judges that a rotation operation is started, and offsets the second boom in a reverse rotation direction when a deceleration start judging device judges that a rotation deceleration operation is started. Accordingly, when a rotation acceleration is performed using a reaction force generated in the offset, clearances between members of a work machine can be contracted in advance in the rotation direction, while when the rotation deceleration operation is performed, these clearances can be contracted in advance in the rotation reverse direction, thereby reducing an impact in the acceleration and deceleration.

Abstract: In a controller, a first switch unit establishes electrical connection between a power-off brake and a power source when a servomotor is energized. The electrical connection causes the power-off brake to be released. A second switch unit is provided between the power-off brake and the power source. The second switch unit establishes electrical connection between the power-off brake and the power source upon being manually operated during the servomotor being deenergized. A calculating unit calculates a driving speed of the joint by the servomotor. A determining unit determines whether the calculated driving speed of the joint is greater than a predetermined threshold speed. An interrupting unit interrupts a supply of electrical power from the power source to the power-off brake through the electrical connection established by the second switch unit when it is determined that the calculated driving speed of the joint is greater than the predetermined threshold speed.

Abstract: The invention relates to a switch arrangement of an electric motor drive (1). The electric motor drive comprises safety switches (3) determined by the safety of the drive, a controlled mechanical brake (4), a power supply circuit (5) of the brake control, a power converter (6), which power converter comprises a network rectifier (7) and a power rectifier (8) of the motor. The power rectifier of the motor is at least partly implemented with controlled semiconductor switches (9, 10) arranged into a bridge. The power converter comprises an intermediate circuit (11, 12) between the network rectifier and the power rectifier of the motor. The switch arrangement comprises normally-open switches (13, 14) in the intermediate circuit of the power converter (6).

Abstract: The start timing of the pole position inference process of the linear motor installed vertically is delayed by a predetermined time after instruction of brake release. For example, from (1) increasing of the thrust instruction value of an ASR control system up to a predetermined value, (2) the movement (falling) distance of the moving part, or (3) the moving (falling) speed of the moving part, the release condition of the brake is detected and moreover after a predetermined time, the inference process of the pole position is started. The inference process of the pole position of a synchronous motor is fit to the release timing of a brake and a malfunction of the inference process and a runaway (falling in the vertical drive) of a moving part are prevented.

Abstract: 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 in a drive or control system for the swiveling electric motor, allowing electric power generated in the electric motor due to inertial rotation to be consumed in an external braking resistor so as to make an electric braking action; and a mechanical brake is activated to stop the rotation and hold the stopped revolving superstructure when a rotation speed of the revolving superstructure becomes equal to or lower than a preset value.

Abstract: A circuit for determining a direction of rotation of an electric motor, the motor having asymmetry and/or eccentricity in a profile of back electromotive force as a function of angular position of a rotor with respect to a stator, the circuit receiving a signal representing the BEMF, and use the corresponding asymmetry and/or eccentricity in the signal to derive the direction of rotation. The signal representing the back emf can be generated by a control circuit. The control circuit can have a feedback loop regulator to generate a control signal (TL or TR) to control a current drive circuit (11,12) to control an amplitude of current (iw) in the windings, the feedback loop regulator being arranged to compare the amplitude of the current (iw) in the windings with a reference value (iset), and use the control signal to provide the signal representing the back electromotive force.

Abstract: An electric motor system includes a motor brake control circuit that uses current induced in the motor stator from generated back EMF to keep the motor brake energized and in its disengaged position, should electric power be lost to the motor system. When the motor has slowed sufficiently that the induced current is no longer sufficient to keep the motor brake energized, the motor brake will move to its engaged position, and prevent further motor rotation. The motor rotational speed at which the motor brake is no longer energized is sufficiently low that any potential degradation or other deleterious effects from motor brake engagement are minimized.

Abstract: An electric braking apparatus including a motor for pressing brake pads on disks, a metal housing for housing the motor, a positive-polarity power line for transmitting power from a battery to the electric motor, a negative-polarity ground line for connecting the electric motor to the ground of a vehicle, and a conductor for electrically connecting the metal housing to the negative polarity of battery or the negative-polarity of an inverter.

Abstract: 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 calculating car body drive force from the above drive force and wheel torque, car body drive force fluctuating component extracting means for extracting multiple frequency band fluctuating components of the car body drive force, and drive or braking force control unit for controlling the running state of a car.

Abstract: A parking brake is released by a controller and a rotating electric motor is speed-feedback-controlled or position-feedback-controlled to stop and hold an upper rotating body if at least one of arm operation, bucket operation, and travel operation is carried out in a rotating stopped state and with respect to the arm operation and the bucket operation, cylinder thrust of an arm cylinder or a bucket cylinder is greater or equal to a set value. Thereby, a parking brake and a rotating driving part can be prevented from being damaged by rotating external force generated by excavation reaction force or the like and a rotating body can be stopped and held.

Abstract: An electric braking apparatus having a conversion mechanism for generating a force for pressing or separating a brake friction member based on a rotational torque generated by an electric motor, wherein a rotor angle position state of the electric motor and a brake process of the brake friction member which is pressed or separated are detected from rotational information of a rotational information obtaining unit, it is detected that the electric motor has reached a predetermined rotational state based on the detected value, and a relationship between a pressure command and the rotor angle position of the electric motor is corrected based on the current value information of the electric motor.

Abstract: 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.

Abstract: Certain exemplary embodiments comprise a system comprising a plurality of Active Front End units adapted to be electrically coupled to a direct current (DC) bus. Each of the plurality of Active Front End units can be adapted to be electrically coupled to a separate winding of a transformer of a plurality of transformers. Each of the plurality of Active Front End units can be adapted to convert alternating current (AC) voltage to a DC voltage. Each of the plurality of Active Front End units can be adapted to supply the DC voltage to the DC bus. The DC bus can be adapted to be electrically coupled to a plurality of inverters.

Abstract: 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 connecting a power source to the bypass circuit. When the brake controlling circuit develops a fault, the brake is directly released by an external power source.

Abstract: 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 industrial-purpose robot is provided, while even when fusion of a contact happens to occur, the control apparatus can firmly interrupt the application of the release voltage to the brake. Also, the control apparatus for the industrial-purpose robot is provided which need not be equipped with a power supply for releasing the brake by an operator in a manual manner.