DE19809814B4 - Method and device for operating a vibration system - Google Patents

Abstract

A method for operating a vibration system, wherein a first main mass (m _F ) and a vibrationally arranged second main mass (m _A ) are vibrated by means of an electric drive means, wherein an actual value X _{SG of} a total vibration width is detected and wherein up to the Operating voltage control of the electric drive unit is achieved by a control variable Y _UB is controlled in response to a predetermined target value W _UB to a constant value, wherein the actual value X _{SG of} the total vibration width with is compared to the setpoint value W _UB and when exceeding the actual value X _{SG of} the total vibration width S _G via a predetermined by the desired value W _UB limit a control deviation is generated, characterized in that the control deviation is fed to a second controller and that the second controller as Total vibration width controller generates a manipulated variable Y _SG , which is subtracted from the predetermined target value W _{UB for} reference value guidance of the first controller.

Description

The The invention relates to a method of operating a vibrating system according to the preamble of claim 1 and to an apparatus for execution this method according to the preamble of claim 5.

A method and a device of the type mentioned is in the DE 196 06 971 A1 described. Therein, a "replacement control" is proposed in which, starting from a predefinable value for the total swing width, there is a change from an operating voltage control to an overall swing control. The device has a single controller, which is preceded by a comparator, the actual values of the total swing width and the operating voltage are supplied, of which a maximum value is provided as the actual size for the downstream controller.

There the operating voltage control during the Gesamtschwingbreitenreglung is inactive, is in the known method not excluded that a flow of bulk material from mains voltage fluctuations or different loads with bulk material dependent is.

From the DE 29 35 739 A1 a method and a device for controlling a resonant vibrating trough with a working mass and a resonance mass are known, which are set in vibration by a rotating imbalance, in particular by an unbalance motor, wherein the amplitude is kept constant in the working mass.

In the CH 666 359 A5 a device for controlling magnetically driven mass vibration systems is described. The device has an electromagnet with which the system can be set to a desired oscillation amplitude.

The GB 2 213 293 A refers to an electronic control for a vibrator. The circuit generates signals for driving an inductive load such as an electromagnet of a vibrator. It is also regulated to a constant amplitude.

In the GB 2 030 731 A is a vibratory conveyor described. The drive is likewise designed as an electromagnet, wherein a constant oscillation amplitude is regulated via an electrical circuit. It is intended to use either the really measured amplitude or a variable proportional to the amplitude such as the voltage or the current through the electromagnet.

By the known measures can be a passing a maximum value for the sum of the vibration amplitudes of the masses can not be prevented.

From the DE 38 13 387 A1 a resonant vibration system is known, which has a control device with which the total swing width of the mutually oscillating masses in the operating range between the unloaded state and the state at maximum Fördergutbelastung (on one of the two masses) is kept constant.

The known resonance vibration system, as a dual mass vibration system is formed, has a natural or resonance frequency, which is with increasing total mass (of the two oscillating masses) to smaller ones Shifts values.

If the resonance vibration system is used in conveyor technology, For example, a vibrating trough is part of a vibrating Dimensions. Granular material is transported on a vibrating trough. If the amount of conveyed material is increased, on the one hand increases the mass coupling at the vibrating trough and the other the damping. In case of increased grainy conveyed that is the friction of the grains increased in their entirety and thus an increase in the damping caused. The resonance curve of the resonance vibration system extends the flatter, the bigger the damping is.

One Operation of the resonant resonance system in the resonance region is with respect to the oscillation amplitude the more critical or unstable, the lower the damping is. On the other hand, one is possible low attenuation sought to keep the power loss low. The working point therefore becomes common in the subcritical or supercritical Area of the resonance curve laid.

at In an operation in the subcritical range, the natural frequency is greater than the drive frequency. With increasing damping finds a reduction the oscillation amplitude instead. Due to the mass coupling is approaching the operating point of the resonance vibration system the resonance point, characterized by the maximum value of the vibration amplitude is. At the same time, the mass coupling reduces the oscillation amplitude the vibrating trough.

Damping and mass coupling thus counteract each other with respect to the vibration amplitude, which leads to a stabilization of the operation in the sense of a compensation of the two effects ("self-helping system"). Since, in the case of resonance, the vibration may be unstable, the known system is set so that taking Berichsich All influences due to the load of the distance to the resonance are so great that a stable operation results. In order to keep the influence of the coupling and damping by the conveyed as low as possible, it is possible to choose the two main masses of the resonant vibration system as large as possible. As a result, a good vibration stability is achieved even in the vicinity of the resonance. However, the high total mass is undesirable from the handling and for cost reasons.

The Total swing width of a resonant vibration system in which a Freimasse and a working mass swing against each other, that is the System state descriptive characteristic. It is between the total swing width, So the sum of the swing width of the free mass and the swing width the working mass, and the vibration width of the work mass - with the Working unit, For example, a vibrating trough, as part - to distinguish. The total swing width as a characteristic has the advantage that they are for Avoidance of the stop operation, ie the juxtaposition of Free mass and working mass, can be used. Such Breaking up is to be avoided at all costs. This is going through the control of the total swing width to a constant setpoint reached.

These Control mode has the advantage that the safety distance between the swinging main masses in favor of higher magnetic power considerably can be reduced, i. the natural frequency can be idle in a vibrating conveyor be adjusted so that the natural frequency at maximum Fördergutbelastung is equal to the drive frequency. In the total swing width control However, the above-described advantage of the self-help Systems (greater system gain at increasing load) not available. A variable vote the natural frequency to the particular circumstances of the use the vibratory conveyor is included the total swing width control not possible.

Of the Invention is based on the object, a method and an apparatus of the type mentioned in such a way that despite monitoring the total swing width the actual useful size, namely the swing width of the utility device, remains constant, i. of load fluctuations and mains voltage fluctuations is independent.

These Task is procedurally by the Characteristics of claim 1 solved.

at The method is a limit control with setpoint control. It will the control variable influencing the electric drive device to a predetermined by a desired size constant value regulated. When passing a limit for the entire swing width is generated a second manipulated variable, the is subtracted from the predetermined setpoint, so that the limited electric actuator influencing manipulated variable becomes.

The Method offers the advantage that on the one hand, the benefits of a "self-help system" are available and at the same time despite surveillance the total swing width the actual useful size, namely the swing width of the utility device, remains constant.

in the Case of application of the method in a vibrating conveyor with a Magnetic drive occurs in the motor-critical operation of the first self-helping effect with constant flow at different Loading with bulk material on; the flow rate is independent of mains voltage fluctuations and loads. at this mode of operation (with a regulation in the operating voltage) arises with increasing total swing the risk of a collision the two main masses (free mass and working mass).

to Avoiding the Aufeinanderschlagens is the regulation specified Setpoint when exceeded a limit for limits the overall swing width before device damage occurs can. Thus lets at the best possible Operating behavior and low safety distance between magnetic core and armature of the magnetic vibrator, i. the power of the vibratory conveyor is optimally utilized. The second manipulated variable associated with the predetermined setpoint results itself from a control difference from the specified setpoint and actual value the total swing width.

In a preferred embodiment, a control deviation between the actual value X _{UB of} the manipulated variable Y _UB and the further desired value W ' _{UB is} supplied to a first controller, and a control deviation between the actual value X _SG and the target value W _UB is fed to a second controller, wherein the control behavior of the first controller compared to the control behavior of the second controller is set faster.

The Control method is characterized in particular by a uniform control method because, when the set point control, i. when linking the predetermined setpoint with the second control variable no discontinuities occur can.

In order to further improve the stability of the control loop, it is provided that the control of the first manipulated variable in comparison to the regulation of second manipulated variable shows a faster behavior.

Of Furthermore, the invention relates to a device for carrying out the Method, with the features of the preamble of claim 5.

there the task is done by device the features of claim 5 solved.

One Operation without a pickup for the total swing width is without a setting change also possible. Should a user not want such a transducer, for example, overseas investments, or should the transducer become inoperative, the plant may without any customization continue to be operated.

Resonant systems with a magnetic drive can be used in voltage-controlled operation. It will be here the effective value of the operating voltage (for the magnetic drive) to one constant value regulated. This measure restricts the mentioned self-help system in no way: with an increase in the working mass (e.g. delivery material in the case of a vibrating conveyor) becomes the controlled system gain of the vibration system, i. the applied by the drive means Effect, automatically raised. This leads to an increased vibration power. This effect is in practical use, for example in a Vibrating trough very advantageous because the discharge of the bulk material of vibrating troughs thus almost independent of loadings and so that is constant.

magnetic drives as drive devices for Resonance vibration systems are very sensitive, causing mains voltage changes concerns, since these directly a disproportionate increase or lowering the magnetic force.

A Voltage regulation compensates for these fluctuations by using as manipulated variable - e.g. the phase angle of the thyristor in a magnetic drive upstream converter - with the Target of constant magnetic force is corrected.

magnetic drives are tuned in the factory to the conveyor. The natural frequency of the resonance system is adjusted. The Voting on the empty device takes place assuming average bulk loadings, the later system behavior influence.

This Average value of course not always on the actual applications too, so both overloading, which leads to the stop against each other vibrating parts, as may also be underutilized. Are these applications known, so by modifying the vote, you can take these special cases into account. Based on the empty device Then there is a different swing width than the nominal swing width.

The Device can for the implementation of the be used method described above. It is, however possible, the actual value for the Total swing width or the RMS acquisition device omit the operating voltage and the device only in the operating voltage or only in total swing-controlled operation, if this for certain applications is sufficient.

Of Furthermore, a programming and / or diagnostic device for a controller for the regulated power supply of vibrating conveyor systems of the above Art proposed, wherein the programming and / or diagnostic device can be coupled with the electronic controller for data exchange.

Around flexible use and easy handling of the programming To achieve and / or diagnostic device, it is provided that the programming and / or diagnostic device as a handheld device with its own and / or external power supply is designed and that operating and display means are provided, on the one hand a setting of parameters of the electronic control or regulation and on the other hand a fault diagnosis by reading one in the electronic control allow integrated memory chip.

By training as a handheld device, especially in the form of a plug-in module is easy to use enabled by the operator. A Internal power supply has the advantage that electronic Controls can be programmed without causing this to operating voltage must be connected. Also a fault diagnosis is possible. The internal power supply is designed so that the Electronic components contained in the electronic control be supplied by the programming and / or diagnostic unit.

at a preferred embodiment the programming and / or diagnostic device is provided that these over a power strip (possibly with a cable connection) with a arranged in a front wall of the control unit terminal block can be coupled.

As a result, the programming and / or diagnostic module can be used flexibly. Also, an infrared interface may be provided. about the data between the programming and / or diagnostics unit and the control unit to be replaced.

Further Details and advantages of the invention are based on the claims and / or in combination with the following description of the drawings to be taken preferred embodiment explained.

It demonstrate:

1 a schematic representation of a resonant vibration system with a magnetic vibrator drive,

2 a block diagram of an apparatus for operating the resonant vibration system,

3 a programmable and / or diagnostic device which can be coupled to a control unit and

4 a block diagram of the programming and / or diagnostic unit.

In 1 is schematically a resonance vibration system 10 with a first main mass or free mass m _F and one of these vibrationally mounted, not necessarily a constant weight during operation main mass or working mass m _A and an electric drive device 12 shown for generating the oscillatory movements. The electric drive device 12 consists of an anchor 14 with its housing part of the free mass m _F and a swingable to the anchor 14 attached magnetic core 16 , which is arranged in the working mass m _A. The free mass m _F is about a spring 18 coupled with the working mass m _A , wherein the spring 18 has a spring constant c. Next to the magnetic core 16 the working mass m _A comprises a conveying trough not shown in detail, in the bulk material 20 to be transported.

The natural frequency f _{e of} the vibratory conveyor results from the formula f e = (c / m R ) ½ . where the resulting mass m _R according to the relationship m R = m F × m A / (M F + m A ) is determined.

The natural frequency f _e can be set to the desired value by changing the spring constant c or the free mass m _F. When idling, the maximum load of conveyed goods must be considered.

In 2 is a device 22 for operating the resonant vibration system 10 shown as a block diagram. A component of the device 22 is designed as a magnetic vibrator drive device 12 connected to an actuator 24 connected. In the embodiment shown here is the actuator 24 designed as a thyristor, for example, operates as a frequency converter, ie from the mains frequency for the operation of the vibrating conveyor 10 desired drive frequency generated, which may be 33 1/3 Hz, for example. The actuator 24 generates an adjustable by phase control of a supply voltage operating voltage U _{B of} the drive device 12 ,

The actuator 24 is a first regulator 26 upstream, the one control deviation of a summing 28 is supplied. The summing element 28 is acted upon by an actual value X _UB and a desired value W ' _UB . The desired value W ' _UB is an output of a summer 30 , on the one hand, a preset target value W _UB and on the other hand, a manipulated variable Y _SG for the total swing of the resonance vibration system 10 is supplied. The manipulated variable Y _SG is from a second controller 32 provided by a summator 34 a control deviation is supplied, wherein the summing element 34 of the preset target value W _UB and an actual value X _{SG of} the total swing width is applied.

For determining the actual value X _{SG of} the total oscillation range S _G between the magnetic core 16 and the anchor 14 of the magnetic vibrator 12 is an actual value transmitter 36 provided by a sampling circuit 38 with the summing element 34 connected is.

The following is the procedure of the device according to the invention 22 to be discribed:
The vibratory conveyor is set by the free mass m _F and the spring constant c at a certain drive frequency f _A for the subcritical operation. By means of the desired value W _UB a regulated operating voltage U _{B is} set, which has a large total swing width S _G , which, however, does not lead to a stacking of armatures 14 and magnetic core 16 leads. The desired value W _UB can in particular be set such that the nominal oscillation range is at a certain frequency, preferably close to the natural frequency f _e .

If no manipulated variable Y _SG is present, the controller is 26 fed the target size W _UB = W ' _UB . The vibrating conveyor operates in operation-voltage-controlled operation with automatic reinforcement with increasing load of conveyed material, so that a higher vibration output is produced. If the actual value X _{SG exceeds} the total vibratory mush te the predetermined target value W _UB , is the controller 32 supplied to a control deviation, so that a manipulated variable Y _SG generated and the summing 30 is supplied. The manipulated variable Y _SG is the desired value W _UB to form a further target value W ' _UB for the controller 26 subtracted. In other words, the controller limits 32 through setpoint control the controller 26 as soon as the total swing width S _{G is} greater than the set value W _UB . The manipulated variable Y _SG is adjustable, so that thus an upper limit of the total oscillation width S _{G is} adjustable. This control method occurs when the natural frequency is close to the operating frequency. It is thereby a striking anchor 14 and magnetic core 16 avoided, although an operation in case of resonance is possible.

The regulator 26 for the operating voltage U _B forms a fast control loop, while the controller 32 forms a slow control loop for the total swing width.

It is provided that the desired value W _{UB is} linearized, in particular as a function of the operating voltage U _B. It can also be provided that the controller 32 a non-linearized nominal value W _{UB is} supplied.

In 3 is a control device 40 shown in the example parts of the device 22 are integrated as a circuit unit. Here are the controllers 26 . 32 designed as digital controller, the internal Regelalgorythmen be changed by programming. It is also provided that extreme values of the total swing width S _G or of voltage fluctuations as well as further errors occurring in the control loop are stored in a memory element.

In control circuits according to the prior art, the control parameters are often set during commissioning of the control loop and can be set after commissioning only by trained personnel. It was also common, a considerable amount of control and display elements in a front of the control unit 40 to implement programming and diagnostics, but at a considerable cost.

It becomes a handy programming and / or diagnostic device 42 suggested that with the control device 40 can be coupled for data exchange. In the embodiment shown here, the connection device 40 a pin header 44 in, in which a arranged on the programming and / or diagnostic device connector module 46 is pluggable. This provides the advantage that programming and / or diagnosing the internal circuitry without opening the device 40 is possible. In particular, a programming or diagnosis on site, ie at the slot of the control device 40 respectively. As a further advantage, it should be noted that on a front page 48 of the control unit 40 fewer controls need to be arranged. The display and operating elements required for programming and diagnostics 50 . 52 are integrated uniformly in the portable and handy programming and / or diagnostic device.

An internal structure of the programming and / or diagnostic device 42 is in 4 shown. The circuit construction consists essentially of a programmable control unit 54 like microcomputer (consisting of CPU 63 and memory 64 ) connected to a power supply 56 connected. The power supply is either a rechargeable battery or an externally powered power supply. For input and output of data is the Mikrocontroler 54 furthermore with an interface 58 connected via the data communication between circuit units of the control device 40 and the microcomputer 54 via data lines 60 . 62 takes place.

Furthermore, the input device 52 and the display device 50 with the microcontroller 54 connected.

Claims (11)

A method for operating a vibration system, wherein a first main mass (m _F ) and a vibrationally arranged second main mass (m _A ) are vibrated by means of an electric drive means, wherein an actual value X _{SG of} a total vibration width is detected and wherein up to the Operating voltage control of the electric drive unit is achieved by a control variable Y _UB is controlled in response to a predetermined target value W _UB to a constant value, wherein the actual value X _{SG of} the total vibration width with the target value W _UB is compared and the total vibration width S _G via a _UB predetermined by the desired value W limit value, a deviation is generated when crossing of the actual value X _SG, characterized in that the control deviation is fed to a second controller and that the second controller al s total vibration width controller generates a manipulated variable Y _SG , which is subtracted from the predetermined desired value W _{UB for} reference value guidance of the first controller. Method according to Claim 1, characterized in that the first controller ( 26 ) compared to the second controller ( 32 ) shows a faster control behavior. Method according to one or more of the preceding claims, characterized in that the manipulated variable Y _SG to be subtracted from the setpoint value W _{UB can be set in} terms of its value by means of parameters. Method according to one or more of the preceding claims, characterized in that as electric drive device ( 12 ) A magnetic drive is used and that as the manipulated variable Y _UB the effective value of the magnetic drive supplying operating voltage UB is specified. Device having a vibration system with a first main mass (m _F ) and a second main mass (m _A ) which is mounted against oscillations during operation and not necessarily a constant weight, and a first regulator with a summing element and an actuator for operating voltage regulation of a drive device for Generation of the oscillatory movements as well as an actual value encoder for detecting an actual value X _{SG of} a total oscillation width S _{G of} the oscillating system, for performing a method according to one of claims 1 to 4, characterized in that the first controller ( 26 ) a second controller ( 32 ) is preceded by the setpoint value guidance of the setpoint value W _UB supplied to the first controller, that the second controller ( 32 ) a summing element ( 34 ) is connected upstream, on the one hand with the actual value encoder ( 38 . 36 ) for the total swing width S _G and on the other hand connected to a terminal for the desired value W _UB and that the second controller ( 32 ) a summing element ( 30 ) is followed at whose first input a manipulated variable Y _{SG of} the second controller ( 32 ) and at whose second input the desired value W _UB is present, and that an output of the summing element ( 30 ) to the desired value guide with the summing element ( 28 ) of the first controller is connected. Apparatus according to claim 5, characterized in that the values for the total swing width S _G and the manipulated variable Y _UB are digitized in constant repetition. Device according to at least one of the preceding claims, characterized in that the actuator is a thyristor ( 24 ), the electric drive means a magnetic drive ( 12 ) and the manipulated variable Y _UB the effective value of the magnetic drive ( 12 ) is feeding operating current. Device according to one of claims 5 to 7, characterized that the device in a vibrator, a vibrating conveyor or in a Rüttelsiebeinrichtung is used. Programming and / or diagnostic device for an electrical Control for the regulated power supply of vibrating conveyor systems according to one of the claims 5 to 7, wherein the programming and / or diagnostic device with the electronic controller for data exchange can be coupled, thereby in that the programming and / or diagnostic device as a handheld device is designed with its own and / or external power supply and that operating and display means are provided, on the one hand a setting of parameters of the electronic control or Control and on the other hand a fault diagnosis by reading a allow in the electronic control integrated memory module. Programming and / or diagnostic device according to claim 9, characterized in that in the electronic control contained electronic components of the programming and / or Diagnostic unit can be supplied. Programming and / or diagnostic device according to claim 9 or 10, characterized in that this via a connector strip (optionally with a cable connection) with a arranged in a front wall of the controller Terminal block (socket or plug) can be coupled.