DE3933266A1 - Controlling electromotor for folding roller shutter - sensing torque and and reversing before shut=off to prevent damage from obstruction or jamming - Google Patents

Abstract

The method for controlling a reversing electric motor (17) uses a drive (19,21) for a folding roller shutter (1). The system is protected against damage or overload arising from a jammed track or other obstruction to movement. A manually operated switch (29) determines the drive direction with inputs (E27,E25) to a reversing unit (27) and torque controller (25) respectively. Torque is measured as a function of motor current and compared with predetermined safe levels with allowance for gravitational differences between up and down travel. Further circuit refinements allow the travel to be automatically reversed during a preset time or turning angle before stopping. USE/ADVANTAGE - Frequently operated doors or screens. Prevents motor from overheating and shutter elements from damage due to track stiction or destructions during closing.

Description

The present invention relates to a method and a Control unit for controlling an electric motor for the Drive a roller shutter, primarily a folding roller shutter.

Electric motor-driven shutters are known. you will be usually with constant predetermined nominal values of electrical supply, especially with constant terminals voltage, operated, be it asynchronous small motors or also DC motors. To reverse the drive direction are, depending on the engine design, the specialist without further ado familiar, the necessary engine-specific order polarity or phase changes in the motor supply taken, while maintaining the mentioned nominal operating values.

Now a roller shutter is a load on the drive motor, which depending on the drive direction with a different Load moment affects the latter. Is the shutter  for example attached to a window at the top, then that it extends from top to bottom the engine load torque is lower than when it was retracted, because the roller shutter with its weight a the Driving torque of the motor provides supporting torque. Even if the roller shutters below are used in certain applications is mounted, works in this case when retracting the Roller shutter, supporting the weight of the roller shutter on that Drive torque. If the roller shutter, as has been customary up to now, in both drive directions with the same drive torque operated, arise in both operating modes disruptive different feed speeds.

The present invention has as its first object to the goal, a method for controlling an electric motor to create a shutter for the drive and a Control unit for this, which eliminates this disadvantage.

This object is achieved with a method according to claim 11 and solved with respect to the roller shutter according to claim 12.

A control unit connected to an electric motor for the An operated a roller shutter remedies the disadvantage mentioned above, is characterized by the features of claim 13, wherein it relates to a roller shutter according to claim 14 is designed.

The above object is therefore achieved in that each according to the drive direction of the electric motor to deliver a Different driving torque is controlled, with what the supportive effect caused by the store's own weight Torque in one drive direction is taken into account and the roller shutter feed in both drive directions same speed.  

However, the present invention relates in particular to the following:
As mentioned above, the present invention relates in particular to the drive control for a folding roller shutter drive. Folding roller shutters are understood to mean a certain type of roller shutter, which essentially comprises dimensionally stable slats which are connected to one another via hinge chains. The slats are stored in an accordion nika-like manner in a housing and are positively drawn out of the memory or fed back into the memory by a drive arrangement.

For this purpose, the drive arrangement also includes a conveyor shaft Conveying flanks on which the conveyed slats are located essentially form-fitting, so that in both Driving directions an essentially non-slip drive connection between shaft and lamellas.

If such a roller shutter is extended, hang for the time being the rigid slats on the coulters provided kidney chains spaced apart from each other until one, e.g. the lowest slat strikes a stop. After that, the distances mentioned are initially canceled, i.e. viewed from bottom to top, it lays down on slat. Is the drive path according to the distances pass between the slats, so all slats have len from the stop to the drive shaft, and another feed harbors the danger that Affect slats, e.g. to bend. That's why the feed movement should be when one of the slats hits a stop and the ones higher up get on each other, the movement is stopped, so as not to damage the roller shutters.  

One problem with this is determining when when the drive should be stopped in such cases. Becomes if he stops too late, they will stay on top of each other the slats overloaded if you take into account that usually between the drive and the shaft mentioned a gear is provided, which also when stopped the drive relieves the lamellae by reacting the lamellar pressing force on the stopped engine allows.

From CH-PS 6 62 868 is now a mechanical solution known problem by a torque limiting Coupling is proposed, which is between the drive and the drive shaft is inserted such that as soon as the load moment, which is about to stop Slats affect the drive and the drive thanks an intended mechanical riddle arrangement empty running.

For manual folding roller shutter drives is from the CH-PS 6 62 868 known coupling based on riddles quite ge suitable, it is readily apparent that a Immediately interrupt the manual drive when she notices that the drive is idling. This is, for example, by the known, then desired Riddling sound immediately noticeable.

But now such a folding roller shutter is electromotive driven, is based on the riddle principle, mechanical torque limitation constructive on the one hand complex, on the other hand problematic in that The clutch is triggered by an unintended An hit, for example, in the path of the roller shutter protruding piece of furniture probably an impairment of the Roller shutter is prevented, but the drive motor when  no additional measures are taken, running empty continues to shoot. On the one hand, this causes annoying puzzles noise and on the other hand leads to a long service life such a facility shortening overuse the clutch. The system further "loses" to it Motor specified stop angle.

The present invention therefore continues and primarily to the goal, a method for controlling a Electric motor for driving a roller shutter which will fix this problem.

This object is ge by the features of claim 1 solves. If the electric motor has passed an angle of rotation, it is fixed in different ways can, the drive direction is either inverted for a predeterminable period of time or for a given angle of rotation and then the motor stops set. That means that at the mentioned angle of rotation, at which shutdown of the roller shutter should take place the drive is not only stopped, but first a relieving movement is initiated by Inver sion of the drive direction for a predetermined time or for a given angle of rotation.

With the features of claim 2 is in a first Design variant proposed that the angle of rotation, at which this inversion should take place becomes. This one or more given turns angles can ent end stops of the roller shutter speak, and by the procedure according to the invention also problems regarding the exactness of the engine shutdown Fixed. For example, tolerance-related inaccuracies in fixing the angle of rotation / stop position  uncritical, since in each case only the relieving mentioned Reversal of movement takes place.

However, the proposed one is particularly advantageous Procedure regarding unforeseeable disturbance attacks, the for example due to icing in the slat guides, Obstacles in the path of movement of the slats or the like, may occur.

With the features of claim 3 is namely in a preferred embodiment provided, if necessary in addition to the possibility of predetermined rotation angles To trigger the inversion movement in advance, the Load moment of the engine and the minimum a rotation angle mentioned as that rotation angle increase in the case of a predetermined change in the load moment occurs or this moment a predetermined Value reached or exceeded.

This is because the folding roller blind is in both directions the at a stop, so there is in essence Lichen non-slip drive connection immediately one Increase the load torque that the drive motor charged. This increase in the load moment will registered, in which the inversion according to the invention takes place.

With the features of claim 4 is preferred the load in a very simple manner moment by measuring the motor current. Either with a DC motor as well as with an asynchronous motor it is well known to the expert that with Er an increase in the load torque is an engine-specific change can be registered with the motor feed current.

Since the problem mentioned at the beginning also with folding roller shutters  of different loads depending on the drive direction moment occurs, is further featured with claim 5 suggest the relief technique mentioned here, with the help the drive inversion according to the invention, with controls a drive direction-specific drive torque combine.

A control unit according to the invention, which be the above Problems discussed regarding the occurrence of attacks solves, is designed according to one of claims 7 or 8. Either there is a trigger signal during a preferably predeterminable time period, a relief signal generated which the drive direction of the motor during inverted this period of time and then stops the motor, or instead of a time specification according to claim 8 a relief stroke specification made.

Should the above mentioned type of malfunction be considered are, it is preferably carried out according to claim 8, i.e. by measuring the motor current, monitors when that Engine torque undergoes a predetermined change, then to generate the trigger signal mentioned.

In combination or alone, if only, or in combination, the drive inversion according to the invention is to be carried out in a predetermined rotational angle position, for example, proposed appropriate end stops, to proceed according to the features of claim 10, i.e. before save given rotation angle of the motor drive, too monitor whether the current angle of rotation is one of the corresponding rotation angle values, in order to then to generate the inversion triggering signal.

The invention is then based on, for example Figures explained.  

Show it:

Fig. 1 schematically based on a func tion block diagram, a first embodiment of a motor control for roller shutters according to the invention using the example of a folding roller shutter, in which the motor is driven to deliver a drive direction-specific drive torque.

Is automatically relieved Fig. 2 schematically with the aid of a radio tion block diagram of a further inventive control, in particular for a Faltrolladen- drive motor, by means of which the stackable shutter position in stop,

Fig. 3 on the basis of a function block diagram, analogous to Fig. 2, a further embodiment variant of the relief control, in which additional shutdown positions for the roller shutter drive can be stored from.

In Fig. 1, the principle of a folding roller shutter 1 is shown schematically, for driving the controls according to FIGS. 2 and 3 are designed, in connection with Fig. 1 and the control shown here, other types of roller shutters can be provided instead of a folding roller shutter.

The folding roller shutter 1 essentially comprises dimensionally stable slats 3 , which are connected to one another via flexible hinge chains 7 . The slats 3 are movably mounted with respect to the hinge chains 7 passing through all the slats, as shown in FIG. 5, stops being provided, as shown schematically in FIG. 9, which determine the spacing of freely hanging slats. The slats are driven via a drive shaft 11 with a polygonal, for example triangular, cross section. Due to the polygonal cross-sectional area, bearing surfaces 13 are formed, which correspond to the height of the slats 3 in such a way that the slats rest flat on the corresponding surfaces 13 .

With the drive shaft 11 can therefore be driven forced lamella on lamella or brought back into a housing 15 and stored there. The shaft 11 is by an electric motor 17 , a DC or asynchronous motor, via a gear 19 and the schematically shown. Shaft connection 21 driven. The electric motor 17 is fed electrically via connections 23 which are shown schematically, depending on the motor type, with direct current or with single-phase or multi-phase alternating current in an asynchronous motor.

In the electrical supply 23 , a torque control unit 25 is provided, which has a control input E ₂₅ . By applying a control signal to the control input E ₂₅ , two different amounts of torque for the electric motor 17 are switchably specified on the torque control unit 25 . In the case of a DC motor, this is done, for example, by setting the motor current, in the case of an asynchronous motor by setting the AC current amplitude.

Furthermore, a drive direction control 27 is easily seen, with a control input E ₂₇ , with the help of which the drive direction of the electric motor 17 , in a DC motor by appropriate polarity reversal in the supply, in an asynchronous motor, for example, by corresponding phase shift of the AC voltage, is controlled.

Furthermore, a switchover unit 29 is provided, on which the desired drive direction is entered, for example manually, at switch inputs UP and DOWN. By activating one of the two UP or DOWN control inputs, a corresponding control signal is applied to input E ₂₇ and input E ₂₅ by switching unit 29 . When the upward movement is actuated, the torque control unit 25 actuates the electric motor 17 with a greater drive torque than when actuating a downward movement.

This causes that by the weight G of the hanging slats on the drive shaft 11 on the elec tromotor 17 retroactive torque, which supports the drive torque in downward movement of the roller shutter, is taken into account in the dimensioning of the drive torque, so that the roller shutter with the same torque conditions and is therefore driven down the same feed speed as it is pulled up again.

In Fig. 2, a first embodiment of a control according to the invention is shown schematically, by means of which a folding roller shutter, as it was presented with reference to Fig. 1, is prevented when it encounters a stop in upward or downward movement because of the in essential slip-free drive between shaft 11 and 3 slats damage.

As stated, for example, the switchover unit 29 outputs corresponding signals UP or DOWN on the aisle side in accordance with its manual activation, for example, for driving the folding roller shutter up or down. These are performed via EXCLUSIVE-OR logic connections 31 to the control unit 27 for the drive direction in the electrical supply for the motor 17 .

Furthermore, a device for measuring the motor load torque is provided, as shown in Fig. 2, preferably in the form of a current measuring device 33 which measures the motor feed current. The output signal of the current measuring device 33 , possibly processed on a processing and amplification unit 35 , is connected to a diffusion unit 37 . The output signal of the differentiation unit 37 is supplied in accordance with the time differential of the loading torque of the motor 17 via a switch S to a comparison unit 39 , which, at a further input, is preferably supplied with an adjustable reference signal. On the output side, the comparison unit 39 is connected to a time setting unit 41 , for example in the form of a monostable multivibra, such that if the signals supplied to the comparison unit 39 match, an output signal of a predetermined time period τ is generated at the time setting unit 41 .

The output of the time setting unit 41 is routed to the EXCLUSIVE OR logic connections 31 . The two outputs associated with the respective operating states of the switchover unit 29 are further guided together with the output of the time setting unit 41 to a logical OR connection 43 , the output of which controls a time setting unit 45 , again for example a monostable multivibrator unit. The output of this unit 45 controls the switch S so that the switch S is open during the occurrence of the output signal of the time period T from the unit 45 .

The arrangement works as follows: If the signal OPEN is generated on the switching unit 29 on the output side, the EXCLUSIVE-OR logic connection 31 on the control 27 for the drive direction switches the electric motor 17 into the desired drive direction. If the folding roller shutter encounters an obstacle or a stop, one of the slats 3 is blocked, as can be seen in FIG. 1, and finally a blocking torque arises on the drive shaft 11 , an increase in the engine load torque. This is measured by the current measuring unit 33 and the differential unit 37 produces an output signal corresponding to this change in torque over time.

When switch S is closed, this output signal corresponding to an increase in load torque is compared with a value that can be set at reference unit 40 . If it is reached, the output signal of the time setting unit 41 is triggered. As a result, the control at the control unit 27 for the drive direction is inverted, in that now, in the case under consideration, the EXCLUSIVE-OR logic connections 31 on the drive direction control unit 27 are used to switch from UP to DOWN operation, specifically during the period τ. After the output signal of the unit 41 drops, as illustrated by way of example, the switching unit 29 switches to the STOP position and the drive is stopped. The switch S is always opened for a given period of time T when the drive is started via the switching control unit 29 in order to render ineffective current changes which occur during the connection of the supply and which do not correspond to a given change in torque with respect to the drive direction inversion according to the invention .

Likewise, the OR connections 43 prevent current transients caused by drive direction inversion from being switched to the comparison unit 39 .

It goes without saying that the expert has many options to implement the concept according to the invention, according to which the drive direction is only inverted at a given load torque increase on the drive motor to relieve the roller shutter lamellae len 3 before the drive is stopped .

On the one hand, FIG. 3 shows a further embodiment variant of the control system shown in FIG. 2, in which it is not current transients that are monitored, but rather the achievement of predetermined current values. In addition, the direction of rotation / drive torque control explained with reference to FIG. 1 is provided in the control shown here. Furthermore, the control is further developed here so that the angle of rotation for the motor 17 can be entered beforehand by hand, the given holding positions for the roller shutter 1 according to FIG. 1, to which the inversion process according to the invention should also be triggered without an obstacle or stop , correspond.

From the switching unit 29 operating according to FIG. 2, the two drive direction control signals are in turn connected via an EXCLUSIVE-OR link 31 of the drive direction control device 27 for the electric motor 17 , but in addition to the torque control unit 25 , which, as explained with reference to FIG. 1 was working, the drive torque determined depending on the drive direction.

The measured in the electrical supply of the electric motor 17 current 33 is in turn a preferred possibility of the load torque measurement, at most via a conditioning and amplification unit 35 , a comparison unit 39 , which also, as switching threshold values depending on the drive direction, an adjustable reference signal is applied by reference signal sources 47 .

Since the reaching of a torque limit value is monitored here and, because of the torque control, 25 different motor currents are set depending on the upward or downward movement of the folding roller shutters, it is necessary to specify two different limit values with the sources 47 . If the signals of the comparator unit 39 match, the time setting unit 41 is in turn triggered, which controls an inversion of the drive direction via the EXCLUSIVE-OR logic connections 31 and then (not shown here) stops the motor, for example with a falling signal edge.

For example, on the mechanical motor shaft is now a rotation angle 49 , for example in the form of a code disk with opto-electronic reader. The output signals of the rotation angle sensor 49 are connected to a storage unit 51 . The present at the input of the SpeI Chers 51 rotation angle values are loaded into the memory 51 cl by activating a control input. The values loaded in the memory 51 appear at the memory output and are connected to a comparator unit 53 , the output of which is connected via an OR connection 55 to the output of the comparison unit 39 and acts on the EXCLUSIVE-OR logic connection 31 .

If the timing unit 41 is triggered when an excessive load torque occurs, on the one hand the inversion process occurs via the EXCLUSIVE-OR logic connections 31 , but in addition the prevailing angle of rotation value is loaded into the memory 41 by activating its control input cl.

After a one-time "learning process" at which the storage unit 51 has been loaded at the positions or stops provided, the switch S _{U can be} opened. During a subsequent operation of the folding roller shutter, the instantaneous rotation angle values are compared at the comparator unit 53 with those stored in the memory unit 51 and the inversion process is triggered if the OR operation 55 matches. If interference stops occur, the device continues to operate via the OR gate 55 , as has been described. The loading of the memory 51 takes place here, for example by registering actual increases in torque in the lower and upper stops.

Another variant provided here is that during the “learning mode” manual instantaneous angular positions are loaded into the memory 51 manually, for example with the M button, via an OR link 57 . Is then found when comparing the current angle of rotation with the manually entered with the button M, at the comparator gate unit 53 , then again via the OR link 55, the default unit 41 , the EXCLUSIVE-OR links 31 , finally the drive direction of the Motor 17 inverted during the period τ.

It is clear to the person skilled in the art that instead of the default a relief time τ the relief also by default a relief rotation angle can be made, the is compared with the current angle of rotation until at Match the engine is stopped.  

Furthermore, it can be provided that when in a primarily controlled drive direction a relief inversion took place, a subsequent re-activation is impossible in the same drive direction as long as the other drive direction was not initially activated.

Claims (16)

1. A method for controlling an electric motor for driving a folding roller shutter ( 1 ), characterized in that after passing through at least one angle of rotation in one direction of rotation, the direction of rotation is inverted for a predetermined period of time (τ) or for a predetermined angle of rotation and then the motor is stopped becomes. 2. The method according to claim 1, characterized in that that at least one angle of rotation is specified. 3. The method according to claim 1 or 2, characterized in that the loading torque of the motor ( 17 ) is recorded and the at least one angle of rotation is defined as that angle of rotation at which a predetermined change in the loading torque occurs or the loading torque reaches a predetermined value. 4. The method according to claim 3, characterized in that the loading torque by measuring the motor current is recorded. 5. The method according to any one of claims 1 to 4, characterized characterized that the drive torque of the electric motors differ depending on the drive direction is given. 6. Application of the method according to one of the claims 1 to 5 on an electric motor for roller shutters Relief of the roller shutter on at least one front seen stop or a fault stop, e.g. an obstacle in the path of the folding roller blind dens. 7. Control unit on an electric motor ( 17 ) for driving a folding roller shutter ( 1 ), characterized in that a time-setting unit ( 41 ) which can be triggered in response to a trigger signal is provided, which triggers out during a preferably predeterminable period of time (τ) generates a relief signal, and that the relief signal inverts a respective drive direction and then stops the motor ( 17 ). 8. Control unit according to the preamble of claim 7 characterized in that one on a trip signal triggerable unit is provided which, triggered, a respective drive direction of the Elek tromotors inverted and that one by triggering signal triggered rotation angle registration unit, off solved, the motor rotation angle registered and the motor after passing through a preferably predeterminable Ent load rotation angle stops.   9. Control unit according to one of claims 7 or 8, characterized in that a measuring device ( 33 ), such as a current measuring device on the motor feed ( 23 ), is provided which detects the engine load torque that the measuring device is connected to a comparison unit ( 39 ) What the output signal of the measuring device is compared with a predetermined reference value ( 4 , 47 ), and that the comparison unit ( 39 ) triggers the trigger signal in the event of a predetermined deviation. 10. Control unit according to one of claims 7 to 9, characterized in that rotation angle values of the motor ( 17 ) can be stored in a storage unit ( 51 ), a measuring device ( 49 ) is provided for the rotation angle currently to be covered, the storage unit ( 51 ) and the measuring device ( 49 ) are guided to a comparator unit ( 53 ), which outputs the trigger signal when the angle of rotation currently covered corresponds to a stored angle of rotation value. 11. A method for controlling an electric motor for driving a roller shutter, characterized in that the drive torque (M) of the electric motor ( 17 ) is predetermined differently depending on the drive direction. 12. A method for control according to claim 11, characterized characterized in that the drive torque in the Rol load downward drive direction smaller is specified.   13. Control unit on an electric motor ( 17 ) for driving a roller shutter, characterized in that it comprises a drive direction-controlled specification unit ( 25 ) for the motor drive torque. 14. Roller shutter with a control unit according to claim 13, characterized in that the default unit ( 25 ), for example by varying the motor current, drives the motor ( 17 ) for delivering a smaller drive torque (M) than when driving the roller shutter ( 1 ) downwards Upward drive. 15. Control unit according to claim 13 with the features according to one of claims 7 to 10. 16. Shutters designed as folding shutters with drive motor and control unit with the characteristics according to min at least one of claims 7 to 10, 13.