Method for operating a drive and drive with brake arrangement

Abstract

Method for operating a drive which has an electric motor with an electromagnetically actuated brake arrangement, wherein a DC voltage applied to the brake coil winding is set in such a way that the brake current increases so slowly, that the time of brake release and the amount of current required to move the armature disk are determined from the temporal course of the current flowing through the coil winding, recorded at discrete times, whereby the engine is accelerated to its target speed after the detected time of brake release.

Description

[0001] The invention relates to a method for operating a drive and drive with an electromagnetically actuated brake arrangement.

[0002] An electromagnetically actuated brake is known from DE 10 2013 005 239 B4.

[0003] From JP 2006 - 2 807 A, the closest prior art is a method for detecting an armature disk.

[0004] A drive with a converter is known from DE 10 2007 022 986 A1.

[0005] From DE 10 2012 008 547 A1 a method is known for determining the wear of a brake pad by determining and evaluating a current kink in the temporal course of the current of a coil of the brake, in particular when the brake is released.

[0006] The invention is therefore based on the object of operating a drive efficiently.

[0007] According to the invention, the object is achieved by the method according to the features specified in claim 1 and by the drive according to the features specified in claim 9.

[0008] Important features of the invention in the method for operating an electromagnetically actuated brake arrangement are that the drive has an electric motor fed by a converter with an electromagnetically actuated brake arrangement, in particular with which the rotor shaft of the electric motor can be braked, wherein the brake arrangement is designed with a coil core, in particular a magnetic body, accommodating a coil winding, and with an armature disk arranged with the coil core in a rotationally fixed but displaceable manner, in particular axially displaceable, in particular in the axial direction of a shaft to be braked, in particular so that the inductance of the coil winding depends on the position of the armature disk, wherein spring elements supported on the coil core press on the armature disc, in particular so that when the coil winding is de-energised the armature disc is pushed away from the coil core and when electrical current is applied the armature disc is pulled towards the coil core against the spring force generated by the spring elements, wherein the temporal course of the current flowing through the coil winding is recorded, in particular by a current sensor, and a current kink occurring during the course of the brake release is detected, in particular by differentiating the curve over time and detecting the exceeding of a threshold value by the differentiated curve, in particular to detect a current kink, where the detection of the current kink - triggers, in particular triggers and / or controls, a change in the target position, in particular the angular position, of the rotor shaft of the electric motor fed by the converter when a position controller of the converter adjusts the actual position, in particular the actual angular position, of the rotor shaft to the target position, - triggers and / or controls a change and / or build-up of the target torque of the electric motor fed by the converter, in particular triggers when a torque controller of the converter regulates the actual torque generated by the electric motor fed by the converter to the target torque.

[0009] The advantage here is that after voltage is applied to the coil winding, it is observed when the current drop caused by the brake being released occurs and the electric motor is started immediately, in particular without delay. This means that the electric motor does not have to work against the brake, but can change its position (i.e., the angular position of the rotor shaft) unhindered by the brake and / or generate torque transmitted to the load via the rotor shaft. There is therefore no need to observe or wait for an additional safety time. In this way, the work processes of the machine or system containing the electric motor can be carried out in a time-efficient manner, in particular as quickly as possible. The drive can therefore be operated efficiently.

[0010] The detection of the current kink thus triggers the transmission of a switch-on signal to the converter, in particular to the signal electronics of the converter, which causes the converter to feed the stator winding of the electric motor in such a way that the rotor shaft rotatably mounted in the housing of the electric motor begins to change its angular position or that a temporally increasing torque of the rotor shaft is made available for transmission to the load.

[0011] The direct use of the detection of the current kink as a trigger signal for switching on the converter enables a reduction of otherwise necessary dead times.

[0012] According to the invention, in the drive with electromagnetically actuated brake, the detection of the current kink when the brake is released is used as a trigger signal for starting the motor of the drive.

[0013] In an advantageous embodiment, a voltage is applied to the coil winding at a first time to release the brake, wherein the time period between the first time and the time of occurrence of the current kink is determined and monitored for exceeding a permissible degree of deviation from a predetermined value, in particular wherein the result of the monitoring is displayed optically and / or transmitted via a data bus in particular, the second setpoint is smaller than the first setpoint. The advantage here is that, based on the time period, an unexpected change in the brake and / or in the electric motor connected to the brake can be detected, displayed, and / or forwarded. For example, at elevated temperatures, the distance traveled by the brake between the brake pad carrier and the magnet body changes, so that the armature disk requires a longer time to travel this distance. The time period to be detected also changes in the event of a power failure or a change in the supply voltage, and can trigger such a display or forwarding of corresponding warning information.

[0014] Important features of the invention in the method for operating a drive are that the drive has an electric motor, in particular fed by a converter, with an electromagnetically actuated brake arrangement, in particular with which the rotor shaft of the electric motor can be braked, wherein in a first time period a DC voltage applied to the brake coil winding is set and built up from zero to a maximum value, that the brake current, in particular the current flowing through the coil winding of the brake arrangement, increases so slowly, that the brake opening, in particular the time at which the brake arrangement is released, and the amount of current required to move the armature disk are determined from the temporal course of the current flowing through the coil winding, which is recorded at discrete times, in particular, wherein at the same time, namely during the first period, the motor is held in position by motor, the engine is accelerated to its target speed after the first period of time, in particular by using the determination of the brake opening as a start signal for accelerating, in particular in the converter.

[0015] The advantage here is that the current rise rate is kept sufficiently low so that the current kink is clearly visible. This is because if the voltage were to be built up suddenly from zero to the maximum value, the current would rise so quickly, depending on the relationship between the maximum value and the inductance of the coil winding, that the current kink could lie between two temporal current sampling points and thus would not be visible. According to the invention, however, the voltage is not built up suddenly, but so slowly that the resulting current increase is so slow that it is still visible even with the discrete current resolution used. The detection of the current kink is then used as a start signal for the inverter to accelerate the motor.

[0016] In an advantageous embodiment, in a first method step, a DC voltage applied to the coil winding of the brake is set in such a way that the detected actual value of the current is regulated to a first setpoint value, in particular so that the brake arrangement is released, in particular wherein a controller sets a DC voltage applied to the coil winding in such a way that the detected actual value of the current is regulated to a first setpoint value, wherein the temporal course of the current flowing through the coil winding is recorded and from this the amount of current necessary, in particular the minimum necessary, to move the armature disk, in particular the one which was previously at rest, is determined, whereby a second setpoint is determined from the sum of this specific current amount and a safety amount, or a second setpoint is determined by multiplying the specific current amount by a factor greater than one, wherein in a fourth method step, carried out after the third method step, the DC voltage applied to the coil winding is set in such a way that the detected actual value of the current is regulated to a second setpoint value, in particular so that the brake arrangement is released, in particular wherein the controller sets the DC voltage applied to the coil winding in such a way that the detected actual value of the current is regulated to a second setpoint value, in particular so that the brake arrangement is released, in particular wherein the second setpoint is smaller than the first setpoint.

[0017] This means that the drive, including the electromagnetically actuated brake, can be operated safely and energy-efficiently.

[0018] The advantage here is that energy can be saved because the holding current, i.e. the amount of current applied to hold the brake in its released state, can be significantly reduced. By determining and evaluating the current kink, the minimum amount of current required for release is determined and can therefore be used. Furthermore, this current is recalculated each time the brake is released, allowing it to be adjusted. If the wear on the brake pads increases and the armature disk is therefore further away from the magnet body before release than with brake pads that have not yet been subjected to wear, the current is adjusted because the current is recalculated after each release.Optionally, the current can be further reduced by using a split coil winding. For release, only one of the two partial windings of the coil winding is initially energized until the current kink is determined and evaluated. The current thus determined is then reduced according to the winding ratio of the two partial windings and, after the current kink is detected and evaluated, is driven through the two partial windings connected in series. This enables very significant energy savings.

[0019] This allows the brake to be operated safely, as the specific current required to hold the brake is continually adjusted to the current condition of the brake, particularly its wear. In every condition, the brake is not only operated safely, especially when released, but also energy-efficiently, as the smallest possible current is used to hold the brake.

[0020] In an advantageous embodiment, the third method step is carried out several times and a respective second target value is determined, The mean of the respective second target values ​​determined is used as the second target value for the fourth process step. The advantage of this method is that outliers that occur during the measurement can be detected by averaging.

[0021] In an advantageous embodiment, a maximum permissible value is used as the initial target value at the beginning of the method. This is advantageous because, when the distance is unknown, the highest voltage is applied first to find the current break and then to determine the holding current value, which can then be used to significantly reduce the electrical power.

[0022] In an advantageous embodiment, in the fourth method step, the temporal course of the current flowing through the coil winding is recorded and from this the, in particular previously static, necessary, in particular minimum, current amount for moving the armature disk is determined, whereby a new second setpoint is determined from the sum of this specific current amount and a safety amount, or a new second setpoint is determined by multiplying the specific current amount by a factor greater than one, The fourth process step is then executed again, using the new second setpoint as the second setpoint. The advantage here is that the holding current value can be adjusted as the brake pads wear.

[0023] In an advantageous embodiment, the coil winding is de-energized before the first process step or at the beginning of the first process step, In particular, the armature disk is pressed against the brake pad carrier by spring elements supported on the brake magnet body, thus remaining stationary relative to the magnet body. The advantage here is that the armature disk is initially stationary, thus maintaining a constant inductance of the coil winding. Only when the armature disk begins to move, thereby changing the distance from the magnet body, does the inductance also change, creating a current kink in the temporal course of the current.

[0024] In an advantageous embodiment, the coil winding is designed as a series circuit comprising a first winding and a second winding, wherein the number of windings of the first winding is smaller than the number of windings of the second winding, whereby in the third and fourth process steps only the first winding is energized, wherein, in a fifth method step, carried out chronologically after the fourth method step, the series circuit is energized, in particular, to hold the brake arrangement in the released state, both the first winding and the second winding are energized. This is advantageous in that rapid release can be achieved, and a current amount determined from the current kink required to hold the brake released is used as the setpoint for energizing the series circuit, a current amount adjusted to the winding ratio of the two partial windings, in particular the first winding and the second winding.

[0025] In an advantageous embodiment, the brake arrangement has a controller whose control value is the voltage applied to the coil winding and to which the difference between the respective setpoint value and the actual value of the current flowing through the coil winding detected at the respective time step is supplied. and that the brake assembly has an evaluation unit designed to determine a respective current kink in the temporal course of the current, particularly when the brake is released. It is advantageous that the voltage can be adjusted such that the current is regulated to its desired value.

[0026] In an advantageous design, the controller is a PI controller or a PID controller. The advantage here is that stable and fast control behavior can be achieved.

[0027] In an advantageous embodiment, the coil winding is designed as a series circuit comprising a first winding and a second winding, wherein the number of windings of the first winding is smaller than the number of windings of the second winding, In particular, the first winding is arranged concentrically with the second winding. The advantage here is that, to release the brake, only one of the two windings is initially energized, allowing the current to build up quickly. After the release process, the second winding is also energized, using a much lower current to keep the brake in the released state.

[0028] In an advantageous embodiment, the coil core is made of a ferromagnetic material, particularly cast steel, especially GGG gray cast iron. This is advantageous because a cost-effective material can be used. Furthermore, axially directed bolts can be pressed into bores in the coil core, which extend through the armature disk and thus guide the armature disk in the axial direction.

[0029] In an advantageous embodiment, the armature disk is made of steel, particularly ferromagnetic steel. This is advantageous because the armature disk can be manufactured from a cost-effective and durable material. Furthermore, good thermal conductivity can be provided to dissipate heat loss resulting from eddy currents.

[0030] In an advantageous embodiment, the brake arrangement has a shaft, in particular the rotor shaft of an electric motor, wherein a brake pad carrier is connected to the shaft in a rotationally fixed and axially displaceable manner, In particular, the armature disk is connected to the coil core, in particular the magnetic body, in a rotationally fixed and axially displaceable manner, and spring elements supported on the coil core, in particular the magnetic body, press against the armature disk. This is advantageous in that in the event of a power failure, the brake is automatically engaged, since the spring elements then press the armature disk onto the brake pad carrier, which is pressed onto a braking surface on its side facing away from the armature disk.

[0031] In an advantageous embodiment, the brake pad carrier has an internal toothing, wherein an annular driver is placed on the shaft and connected in a form-fitting manner, in particular by means of a key connection, The driver has external teeth onto which the brake pad carrier is mounted with its internal teeth, in particular, the external teeth meshing with the internal teeth. It is advantageous that the brake pad carrier is axially displaceable relative to the driver and is connected in a rotationally fixed manner in the circumferential direction.

[0032] In an advantageous embodiment, the armature disk is arranged in the axial direction, in particular in the direction of the shaft's axis of rotation, between the coil core, in particular the magnetic body, and the brake pad carrier. The advantage here is that the armature disk is drawn toward the magnetic body against the spring force generated by the spring elements when the coil winding is energized, and is pressed toward the brake pad carrier by the spring elements when energized. The armature disk is guided in the axial direction and connected to the magnetic body in a rotationally fixed manner. In contrast, the brake pad carrier is connected to the rotatably mounted rotor shaft in a rotationally fixed manner and is also arranged to be displaceable in the axial direction.

[0033] In an advantageous embodiment, the brake pad carrier is arranged axially between the armature disc and a braking surface. This advantageously allows the armature disc to be pressed onto the brake pad carrier by the spring elements, thus forcing the brake pad carrier toward the braking surface, particularly on the side facing away from the armature disc.

[0034] Important features of the electric motor are that the electric motor has an aforementioned brake arrangement, in particular wherein the brake arrangement is arranged on the axial side of the rotor shaft of the motor facing away from the load driven by the motor.

[0035] The advantage here is that the attachment of the load is not hindered by an intermediate brake. Thus, the brake can be provided on the B side and the load can be connected on the A side.

[0036] Further advantages emerge from the dependent claims. The invention is not limited to the combination of features in the claims. Further possible combinations of claims and / or individual claim features and / or features of the description and / or the figures will become apparent to those skilled in the art, particularly from the problem and / or the problem posed by comparison with the prior art.

[0037] The invention will now be explained in more detail with the aid of illustrations: In the Fig. 1 shows a cross section through a first embodiment of a brake arrangement according to the invention for a motor, in particular an electric motor.

[0038] As in Fig.1, in a magnetic body 4, in particular a GGG steel casting, i.e. ferromagnetic steel casting, an annular recess is formed as a receiving area, in which an electrically energizable coil winding 3 is received.

[0039] When the toroidal coil is energized, an armature disk 8 which is connected to the magnetic body 4 in a rotationally fixed manner but is arranged so as to be displaceable towards the magnetic body and which is preferably guided during movement by means of guide parts, in particular bolts, which are firmly connected to the magnetic body 4, is pulled towards the magnetic body 4 against the spring force of spring elements 10 which are supported on the magnetic body 4.

[0040] The spring elements 10 are each arranged at the same radial distance from the axis of the shaft to be braked, in particular the rotor shaft of an electric motor, wherein they are each at the same distance from one another in the circumferential direction, in particular are evenly spaced from one another in the circumferential direction.

[0041] A part having a braking surface, in particular a housing part or bearing flange for accommodating the bearing of a shaft, in particular a rotor shaft, is spaced apart from the magnetic body 4 and firmly connected to it. The guide parts designed as spacer bolts serve to maintain the spacing.

[0042] A lining carrier 12, which is connected to the shaft in a rotationally fixed but movable manner, particularly in the direction of the shaft axis, and has brake linings (11, 13) arranged on both sides, particularly in and against the shaft axis, is arranged between the armature disk 8 and the braking surface. When current is applied to the coil winding 3, the armature disk 8 is thus pulled away from the braking surface, thus releasing the brake. When current is not applied to the coil winding 3, the spring elements 10 press the armature disk 8 onto the lining carrier 12, which is thus pressed onto the braking surface. In this way, an electromagnetically actuated brake is produced.

[0043] Preferably, an annular driver is mounted on the shaft and connected to the shaft in a rotationally fixed manner by means of a keyway. The driver has an external toothing, onto which an internal toothing of the lining carrier 12 is mounted.

[0044] When energized, the armature disk 8 is accelerated and only stopped when it strikes the magnet body 4 or, if applicable, a sheet metal part arranged between the armature disk 8 and the magnet body 4, such as a damping plate or the like. This creates an impact noise, which is somewhat dampened in the case of the intermediate sheet metal part.

[0045] The armature disk 8 is preferably made of a ferromagnetic steel. The magnet body 4 is also made of a ferromagnetic cast steel.

[0046] Additional improved noise damping is achieved by means of a stamping part 7 arranged on the armature disk 8, in particular a fixed part. The stamping part 7 has a conical section that can be accommodated in a corresponding internally conical section of a sleeve 5. The edge of the internally conical section of the sleeve 5 is designed with a thin wall, i.e., a small wall thickness.

[0047] The sleeve 5 is firmly connected to the magnetic body 4. The magnetic body preferably has an axially continuous recess, i.e. in the shaft axis direction, in which the sleeve is arranged.

[0048] A screw part with screw head or nut 1 is guided through the recess from the side of the magnet body 4 facing away from the lining carrier and is screw-connected to the sleeve 5. This sleeve 5 can thus be fixed axially.

[0049] Alternatively, the sleeve 5 is simply inserted into the recess of the magnet body 4 and held in place by an O-ring 17 located on its outer circumference. For this purpose, the O-ring 17 has an oversize in the relaxed state, so that it is elastically deformed upon insertion into the recess. The sleeve has another O-ring 6 on its outer edge, which is also firmly connected to the recess and pre-damps the inner conical area.

[0050] Thus, the sleeve 5 is frictionally connected to the magnet body via the O-rings (6, 17). Furthermore, when the plunger part 7 impacts the sleeve 5, particularly when the conical section of the plunger part 7 increasingly comes into contact with the inner conical section of the sleeve 5, the inner conical region of the sleeve 5 expands and is thus deformed. At least the O-ring 6, which is arranged against a shoulder of the sleeve 5, is also squeezed outward at its circumference, thereby achieving evaporation.

[0051] In addition, when the punch part 7 impacts the sleeve 5, in particular when the conical section of the punch part 7 increasingly comes into contact with the inner conical section of the sleeve 5, the sleeve 5 is axially displaced against the spring force generated by the O-rings (6, 17) held in the receptacle of the magnetic body 4. This also contributes to pre-damping.

[0052] The cone angle of the conical section of the punch part 7 is more acute, i.e. smaller, than the opening angle of the inner conical section of the sleeve 5.

[0053] Although the two angle values ​​differ by only less than 20° or even less than 10°, this small, non-negligible angle difference is sufficient for effective damping.

[0054] Overall, the impact is pre-damped on the one hand by the O-rings (6, 17) made of elastic material, in particular plastic or rubber, and on the other hand by the cone angle difference between the conical area of ​​the punch part 7 and the inner conical area of ​​the sleeve 5.

[0055] The electrically energizable coil winding 3, in particular coil, has an inductance which depends on the distance between the armature disk 8 and the magnetic body 4. When the energization is stopped, the spring elements 10 supported on the magnetic body 4 press the armature disk 8 away from the magnetic body 4, whereby the inductance changes and the brake is applied, i.e. the armature disk 8 is pressed onto the lining carrier 12, which is pressed onto the braking surface of the part 15 on its side facing away from the magnetic body 4.

[0056] To release the brake, a direct voltage is applied to coil winding 3. This causes an increase in the current flowing through coil winding 3, which is detected by a sensor, in particular a current sensor. As soon as the magnetic attraction force acting on armature disk 8, which increases with the current, overcomes the spring force generated by spring elements 10, armature disk 8 is accelerated and moves toward the magnetic body 4. The temporal current curve forms a kink and increases with a different gradient due to the changed inductance after impact of armature disk 8.

[0057] The time interval from the start of the application of the direct voltage to the coil winding 3 until the current kink depends on the wear of the brake pads 11 on the pad carrier 12, since in the applied state of the brake, i.e. before the direct voltage is applied to the coil winding 3, the axial thickness of the brake pads determines the position of the armature disk 8 and thus the distance of the armature disk 8 from the magnet body 4.

[0058] As known from DE 10 2012 008 547 A1, the wear of the brake pads 11 can therefore be determined by determining this time interval.

[0059] According to the invention, the current flowing through the coil winding, i.e. the actual value of the current, is detected and the voltage applied to the coil winding 11 is adjusted in such a way that the detected actual value of the current is regulated to a predetermined target value of the current.

[0060] When the brake is first released, the maximum possible DC voltage is applied to the toroidal winding 3, and then the current required to achieve the current break is determined. A setpoint current is then determined, which is determined as the sum of this specific current and a safety factor, or by multiplying the specific current by a factor greater than one, thus adding a safety factor to the specific current.

[0061] Optionally, this ventilation process can be repeated several times and an average value is calculated from the respective setpoints, which is then used as the setpoint for subsequent ventilation.

[0062] During one or subsequent brake release, the voltage is adjusted such that the actual current is regulated to the setpoint. Thus, the maximum current achieved is lower than if the full available DC voltage were applied to coil winding 3. This enables a reduction in power loss, since a lower current is required to maintain the brake in the released state, rather than the maximum possible current that would occur at the maximum available voltage, thus resulting in lower ohmic losses.

[0063] Preferably, a factor between 1.1 and 1.5 is used.

[0064] This allows the setpoint to be adjusted even with increasing wear of the brake pads. Because the distance between the armature disk 8 and the magnet body 4 increases with increasing wear when the brake is applied, a correspondingly increasing setpoint is necessary.

[0065] The brake assembly is mounted on the B-side of the electric motor to brake the rotor shaft of the electric motor. The resulting brake motor drives a load. Preferably, the load is connected to the A-side of the electric motor.

[0066] The electric motor is powered by an inverter, which provides a three-phase voltage to the stator winding of the electric motor.

[0067] However, the electric motor is preferably operated in position control, and a setpoint position is only changed when the brake is released. As soon as the current drop is detected, the inverter is given the go-ahead to change the previously constant setpoint position. This means that the electric motor does not have to work against the brake, but can move the load.

[0068] However, if the electric motor is operated in torque control, torque generation only begins after the current drop is detected. This means that the brake is not counteracted.

[0069] In any case, according to the invention, no time is lost, but the movement is effected by the electric motor immediately after the current kink is reached, i.e. the brake is released.

[0070] This enables high clock rates in the machine or system containing the electric motor as a drive, in particular with dead times being eliminated or at least reduced.

[0071] Furthermore, monitoring of the time elapsed from the activation of the release process (i.e., the start of energization of the brake coil winding) until the target position is left in position control or until torque is generated (especially a non-zero torque) in torque control is possible, to determine whether a permissible deviation from the target time period has been exceeded. This allows for early detection of errors and / or damage.

[0072] The electric motor is preferably a three-phase motor. If the electric motor is designed as a synchronous motor, a single-phase load is applied to the three-phase winding while maintaining a fixed angular position.

[0073] In further embodiments according to the invention, the course of the detected current flowing through the coil winding is differentiated and the resulting signal is fed as a switching edge to an input of the signal electronics of the converter, so that a clearly recognizable input signal at the converter triggers the generation of the three-phase voltage for the electric motor, which then starts the movement of the rotor shaft.

[0074] In further embodiments of the invention, a first number of ventilation processes are carried out with the identical setpoint value, and the new setpoint is determined by the aforementioned averaging, which is then used for a second number of ventilation processes. Preferably, the second number is equal to the first number.

[0075] In further embodiments of the invention, the current waveform upon application of the brake is also evaluated, and after the DC voltage is switched off, the current flowing through a freewheeling diode connected in parallel with the coil winding 3 is recorded. In this case, a change in the inductance also allows a kink in the current waveform, in particular a current kink, to be detected and evaluated.

[0076] In addition, the current kink analysis can be used to determine the current wear level of the brake and display it or forward it via a data bus connection.

[0077] In further embodiments according to the invention, the coil winding is designed as a split winding, i.e., consisting of two partial windings. Thus, during release, only one of the partial windings is energized as long as the armature disk is not yet accelerated. However, as soon as the armature disk is accelerated and the brake assembly is thus released, the series connection of the two partial windings is energized, and thus the only necessary holding current, reduced according to the ratio of the number of windings in the partial windings, is conducted through both partial windings. List of reference symbols 1 mother 2 coil carriers 3 Coil, especially coil winding 4 magnetic bodies, cast steel, ferromagnetic 5 sleeve 6 O-ring 7 Stamp part 8 Anchor disc 9 Adjusting screw 10 spring element 11 Brake pad 12 lining carriers 13 Brake pad 14 Driving teeth 15 Part having a braking surface, in particular a housing part or bearing flange for receiving the bearing of a shaft, in particular a rotor shaft 16 Lock nut 17 O-ring QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] DE 10 2013 005 239 B4

[0002] JP 2006 - 2 807 A

[0003] DE 10 2007 022 986 A1

[0004] DE 10 2012 008 547 A1 [0005, 0058]

Claims

[1] Method for operating a drive which has an electric motor fed by a converter with an electromagnetically actuated brake arrangement, in particular with which the rotor shaft of the electric motor can be braked, wherein the brake arrangement is designed with a coil core, in particular a magnetic body (4), which accommodates a coil winding, and with an armature disk (8) arranged with the coil core in a rotationally fixed but displaceable manner, in particular axially displaceable, in particular in the axial direction of a shaft to be braked, in particular so that the inductance of the coil winding depends on the position of the armature disk (8), wherein spring elements (10) supported on the coil core press on the armature disc (8), in particular so that when the coil winding is de-energized, the armature disc (8) is pushed away from the coil core and when electrical current is applied, the armature disc (8) is pulled towards the coil core against the spring force generated by the spring elements (10), characterized by , that wherein the temporal course of the current flowing through the coil winding is recorded, in particular by a current sensor, and a current kink occurring during the course of the brake release is detected, in particular by differentiating the curve over time and detecting the exceeding of a threshold value by the differentiated curve, in particular to detect a current kink, where the detection of the current kink - triggers, in particular triggers and / or controls, a change in the target position, in particular the angular position, of the rotor shaft of the electric motor fed by the converter when a position controller of the converter adjusts the actual position, in particular the actual angular position, of the rotor shaft to the target position, - triggers and / or controls a change and / or build-up of the target torque of the electric motor fed by the converter, in particular triggers when a torque controller of the converter regulates the actual torque generated by the electric motor fed by the converter to the target torque. [2] Method according to claim 1, characterized by , that to release the brake, a voltage, in particular direct voltage, is applied to the coil winding at a first point in time, wherein the time period between the first time and the time of occurrence of the current kink is determined and monitored for exceeding a permissible degree of deviation from a predetermined value, in particular wherein the result of the monitoring is displayed optically and / or reported via a data bus. [3] Method for operating a drive which has an electric motor, in particular fed by a converter, with an electromagnetically actuated brake arrangement, in particular with which the rotor shaft of the electric motor can be braked, wherein in a first method step a DC voltage applied to the brake coil winding is set in such a way, in particular and is built up from zero to a maximum value, that the brake current, in particular the current flowing through the coil winding of the brake arrangement, increases so slowly, that the brake opening, in particular the time of brake opening, in particular the time of release of the brake arrangement, and the amount of current required to move the armature disk (8) are determined from the time course of the current flowing through the coil winding, which is recorded at discrete times, in particular, wherein at the same time, namely during a first period of time, the motor is held in position by motor, wherein, in particular in a second method step, after the first method step, the determination of the brake opening is used as a start signal for accelerating the engine and / or the engine is accelerated to its target speed after the first time period, in particular by using the determination of the brake opening as a start signal for accelerating, in particular in the converter. [4] Method according to at least one of the preceding claims, characterized by , that in a third method step, a DC voltage applied to the coil winding of the brake is set in such a way that the detected actual value of the current is regulated to a first setpoint value, in particular so that the brake arrangement is released, in particular wherein a controller sets a DC voltage applied to the coil winding in such a way that the detected actual value of the current is regulated to a first setpoint value, wherein the temporal course of the current flowing through the coil winding is recorded and from this the amount of current necessary, in particular minimum, to move the armature disk (8), in particular which was previously at rest, is determined, whereby a second setpoint is determined from the sum of this specific current amount and a safety amount, or a second setpoint is determined by multiplying the specific current amount by a factor greater than one, wherein in a fourth method step, carried out after the third method step, the DC voltage applied to the coil winding is set in such a way that the detected actual value of the current is regulated to a second setpoint value, in particular so that the brake arrangement is released, in particular wherein the controller sets the DC voltage applied to the coil winding in such a way that the detected actual value of the current is regulated to a second setpoint value, in particular so that the brake arrangement is released, in particular wherein the second setpoint is smaller than the first setpoint. [5] Method according to at least one of the preceding claims, characterized by , that the third process step is carried out several times and a respective second target value is determined, wherein the mean value of the respectively determined second target values ​​is used as the second target value for the fourth method step. [6] Method according to at least one of the preceding claims, characterized by that at the beginning of the procedure a maximum permissible value is used as the first setpoint. [7] Method according to at least one of the preceding claims, characterized by , that in the fourth method step, the temporal course of the current flowing through the coil winding is recorded and from this the, in particular previously static, current amount necessary, in particular minimum, to move the armature disk (8) is determined, whereby a new second setpoint is determined from the sum of this specific current amount and a safety amount, or a new second setpoint is determined by multiplying the specific current amount by a factor greater than one, wherein the fourth method step is carried out again and the new second setpoint is used as the second setpoint. [8] Method according to at least one of the preceding claims, characterized by , that the coil winding is de-energized before the first process step or at the beginning of the first process step, in particular wherein the armature disc (8) is pressed against the brake pad carrier (12) of the brake by spring elements (10) supported on the magnetic body (4) of the brake and thus rests relative to the magnetic body (4). [9] Method according to at least one of the preceding claims, characterized by , that the coil winding is formed as a series circuit comprising a first winding and a second winding, wherein the number of windings of the first winding is smaller than the number of windings of the second winding, whereby in the third and fourth process steps only the first winding is energized, wherein in a fifth method step, carried out after the fourth method step, the series circuit is energized, in particular to hold the brake arrangement in the released state, both the first winding and the second winding are energized. [10] Drive with brake arrangement for carrying out a method according to at least one of the preceding claims, characterized by , that the brake arrangement has a controller whose control value is the voltage applied to the coil winding and to which the difference between the respective setpoint and the actual value of the current flowing through the coil winding recorded at the respective time step is supplied and that the brake arrangement has an evaluation unit which is designed to determine a respective current kink in the temporal course of the current, in particular when the brake is released, in particular wherein the time constant of the controller is greater, in particular at least five times greater, than the quotient of the amplitude, in particular the kink height, of the current kink and the maximum current change rate of the current kink, in particular so that the controller only regulates the current kink after a period of time whose amount is a multiple of the time constant. [11] Drive according to at least one of the preceding claims, characterized by , that the controller is a PI controller or a PID controller, and / or that the coil winding is formed as a series circuit comprising a first winding and a second winding, wherein the number of windings of the first winding is smaller than the number of windings of the second winding, in particular wherein the first winding is arranged concentrically to the second winding. [12] Drive according to at least one of the preceding claims, characterized by , that the coil core is made of a ferromagnetic material, in particular cast steel, in particular GGG grey cast iron, and / or that the armature disk (8) is made of a steel, in particular of a ferromagnetic steel. [13] Drive according to at least one of the preceding claims, characterized by , that the brake arrangement has a shaft, in particular the rotor shaft of an electric motor, wherein a brake pad carrier (12) is connected to the shaft in a rotationally fixed and axially displaceable manner, in particular wherein the armature disk (8) is connected to the coil core, in particular the magnetic body (4), in a rotationally fixed and axially displaceable manner and wherein spring elements (10) supported on the coil core, in particular the magnetic body (4), press onto the armature disk (8). [14] Drive according to at least one of the preceding claims, characterized by , that the brake pad carrier (12) has an internal toothing, wherein an annular driver is placed on the shaft and connected in a form-fitting manner, in particular by means of a key connection, wherein the driver has an external toothing onto which the brake pad carrier (12) is placed with its internal toothing, in particular wherein the external toothing is in engagement with the internal toothing. [15] Drive according to at least one of the preceding claims, characterized by , that the armature disc (8) is arranged in the axial direction, in particular in the direction of the axis of rotation of the shaft, between the coil core, in particular the magnetic body (4), and the brake pad carrier (12), and / or that the brake pad carrier (12) is arranged in the axial direction between the armature disc (8) and a braking surface (15). [16] Drive according to at least one of the preceding claims, wherein the drive comprises an electric motor with a brake arrangement, in particular wherein the brake arrangement is arranged on the axial side of the rotor shaft of the motor facing away from the load driven by the motor.

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