DE20306134U1 - Electric motor regulating drive especially for furniture drives, has variable end switching positions for linear and rotational movement - Google Patents

Abstract

An electric motor regulating drive for low voltage uses, especially in furniture, comprises a motor (2) with an adjustable and/or rotatable drive element (4) having two end positions (19,20) with a hand-operated selector (6,13). There is a switch point (21,22) between the end positions to alter the operation.

Description

Dewert Drive and System Technology GmbH & Co. KG, Weststrasse 1, 32278 Kirchlengern
"Electromotor actuator with variable limit switches"

The invention relates to an electromotive actuator for low-voltage applications, in particular furniture drive, with at least one motor with an adjustable and/or rotatable output element, the adjustment path and/or angle of rotation of which has a first end position and a second end position, with a position sensor, with at least one manual control, with at least one control, and with a power supply which has at least one mains-dependent voltage source, or at least one mains-dependent and one mains-independent voltage source.

The electromotive actuator is preferably used for adjusting functional furniture. On the one hand, it is a linear drive in which the rotary movement of a motor is converted into a longitudinal movement of an output element. On the other hand,

-25./710/185-

Hollerallee 32 · D-28209 Bremen · P.O.B. 10 71 27 · D-28071 Bremen · Telephone+49-421-34090 · Fax+49-421-3491768

MUNICH - BREMEN - BERLIN - DÜSSELBORUSS · FRANKFURT- BIEDEFELB*- POTSD,*!MJ-«WIEL - PABERBOR]^ -J ₁ AJIpSHU^- H(JHENfIRCHEN - ALICANTE - PARIS

me»t*de'··* *··* '••*e-ma»l?po*stmaster*^boehrnwt.de···

BOEHMERT & BOEHMERT "

-2-

On the other hand, it can also be a rotary drive in which the output element performs a pivoting or rotating movement.

WO 01/70165 A1 discloses an electromotive drive unit which has a comprehensive control system. This control system is equipped with freely programmable limit switches. However, the large size and economic outlay of such a control system proves to be a disadvantage, and programming the limit switches using a suitable device is also cumbersome.

Furthermore, different drive concepts of the type described in more detail above are known, which also have limit switches, for example in the form of microswitches, which are fixed and have fixed switching points. In some designs, these limit switches are also adjustable from the outside. The disadvantage here is that the position and installation of the fixed limit switches is only possible during assembly of the drive units. Subsequently changing the switching point of movable limit switches is complex, as adjustment can only be carried out by specialist personnel and with special tools. Furthermore, this requires difficult cable routing inside the drive. In addition, a waterproof design is not possible, as the drive must be open to insert the adjustment tool. A further disadvantage is that external limit switches require their own housing with special cable routing, the switching command must be transmitted through the housing of the drive, which results in high costs both in the number of parts and in production and maintenance.

The object of the invention is to provide an electromotor actuator with limit switches which can be adjusted in the simplest way during production, whereby subsequent adjustment of the same is also possible in the simplest way.

BOEHMERT & BOEHMEUT "

-3-

This object is achieved according to the invention in that between the first end position and the second end position of the adjustment path and/or angle of rotation of the output element, at least one switching point is assigned to a position of the adjustment path and/or angle of rotation of the output element at or at any distance from the first end position and at or at any distance from the second end position, wherein this assignment is designed to be changeable.

Advantageous developments of the invention are contained in the subclaims.

In the preferred embodiment, the assignment of the switching points to the end positions is carried out in a specific operating state when setting up the drive. For this purpose, the drive has a position sensor, which is preferably arranged in the motor, coupled to it and consists of Hall sensors. The motor is moved to its end positions at a slow speed using a control and a manual control in this so-called process. The end positions have either mechanical stops that are located in the drive itself or on the part of the furniture to be adjusted. When the drive reaches these end positions, the current of the drive motor increases. This increase in current is detected by a current monitoring module in the control and passed on to a control module. At the same time, the associated position value from the motor's position sensor is made available to the control module via an evaluation circuit. The control module now assigns the position value to the end position by storing this position value in a memory module. At the same time, further information is stored that causes the control to switch off the motor when this position value is reached.

In a preferred embodiment, a percentage or predetermined value is advantageously added to the position value in the respective end position, which allows the motor to switch off before the position is reached, so that the motor does not have to reach the mechanical stop.

BOEHMERT & BOEHMERT "

-4-

The electromotive adjustment drive preferably has additional actuating elements on the manual control or on the control or on the motor or with which a switching point of the control can be entered when a certain position is reached. For example, the switching points for the end positions can also be entered using this actuating element. In one embodiment, an automatic setting of these switching points is then not necessary. In this case, it is advantageous if, when entering the switch-off points for the end positions, the safety values or safety distance between the end position and the switching point are added as a percentage using a previously defined value.

Using the actuating element, it is also advantageously possible to subsequently change the assigned switching points for the positions of the adjustment drive. To do this, either a limited number of additional switching points can be added, or existing switching points can be deleted or overwritten. The switching points can be deleted using a specific key combination on the manual control or on a special maintenance manual control. Other options are conceivable.

In a preferred embodiment, an actuating element, preferably a Hall sensor, is located within the hand control and can be actuated with a magnetic key that can be applied from the outside.

In a further embodiment, an actuating element is arranged on the control.

It is advantageous to arrange the actuating element on the motor. This can be a membrane button that is operated using a tool.

It is advantageous for the control system to have an optical and/or acoustic signalling module. This signalling module issues appropriate signals which inform the user about the operating status of the drive or its stored switching points.

BOEHMERT & BOEHMERt ^##

-5-

The acknowledgement signal can be, for example, a relay clicking several times. Other signal forms are known and can be used. The invention is not limited to the embodiment described. It is important that the switching points in the end positions and additional switching points can be entered and subsequently changed in an advantageously simple manner using an actuating element at the corresponding position of the drive. This advantageously means that extensive storage of drives in different lengths with different limit switches is no longer necessary. A drive can be adapted for a specific customer shortly before the customer order is placed.

It is thus possible in a particularly advantageous manner to be able to specifically adjust manufacturing tolerances of both the drive and the equipment to be driven by means of the invention by adjusting the switching points, in particular subsequently and also on site.

In a further embodiment, the controller has a connection interface at which a signal is made available in a suitable form for further processing when the switching points are reached.

Furthermore, it is possible that, for example, the limit switches of the retracted and extended positions and/or intermediate positions are provided as conventional, permanently installed elements, whereby additional end and/or intermediate positions can be entered.

The invention is explained in more detail in the following description with reference to the drawing. Here:

Fig. 1 is a schematic representation of an embodiment of an electromotor actuator with control, manual operation and various switching points.

·

BOEHMERT & BOEHMERt "
-6-

Figure 1 shows an exemplary embodiment of an electromotive actuator 1, which is shown here as a linear drive in a single version with a manual control 6 and a control 5. A motor 2 is connected to this, which is coupled to a gear 3. The gear 3 is, for example, a worm gear with a spindle and spindle nut gear for generating a linear movement from a rotary movement of the motor 2, with an output element 4 that is adjustable in the longitudinal direction.

The electrical connection of the motor 2 is made to the control 5 at a motor connection 26, to which a position sensor 13 is also connected. In the preferred embodiment, the position sensor 13 is located on/at the motor. The position sensor 13 consists, for example, of a Hall element unit which, depending on the number of revolutions of the motor 2, supplies electrical signals which are assigned to adjustment positions of the output element 4.

The representation of the electrical connection of the motor 2 and the electrical connection of the position sensor 13 are shown separately in the illustration in Figure 1, but in a preferred embodiment are laid within one cable.

The electric motor actuator 1 is supplied with power via a power supply cable 27. This can be provided in a design with an external power supply 29 via a power supply connection 30 on the control 5, or by the power supply cable 27 being connected directly (not shown) to the power supply connection 30 of the control 5, in which case an internal power supply 28 is arranged in the control 5.

The manual control 6 is connected to the control 5 via an operating connection 25. The manual control 6 has first actuating elements 7 and 7' for each adjustment direction of the motor 2. When a first actuating element 7, 7' is actuated, the signal is forwarded to a control module 16 via the operating connection 25 in the control 5.

BOEHMERT & BOEHMOKT * * *

-7-

which switches the motor 2 on or off in the respective adjustment direction via a current monitoring module 17 and the motor connection 26.

The current monitoring module 17 switches off the motor in a known manner if it consumes too much current due to overloads or blockages. The current values of the running motor 2 determined in this way are fed into the control module 16 for further processing via a feedback 31.

An evaluation module 14 receives and processes the signals from the position sensor 13. The evaluation module 14 can also simultaneously evaluate and process the signals from the position sensor 13 in such a way as to relieve the function of the control module 16.

Furthermore, a fourth actuating element 11 is provided within the control system 5 for input into the control module 16. A signaling module 18 can be activated by the control module 16 in such a way that optical and/or acoustic signaling signals are generated in certain situations and operating states of the drive 1.

A memory module 15 is also arranged within the control unit 5. It is used to store operating states of the motor 2, default values for the current monitoring module 17, and to store certain adjustment positions of the drive 1. A detailed explanation of this is given below.

The adjustment path of the output element 4 is limited by a first end position 19, which is located in the lower area in the embodiment shown here. In the upper area of the adjustment path of the output element 4, its adjustment path is limited by a second end position 20. These limits are designed as mechanical end stops that are suitable for the forces that occur. Before the output element reaches these first and second end positions 19, 20 and is thus blocked, the motor is

BOEHMERT & BOEHMERT

-8th-

reaching the end positions 19, 20 in a first switching point 21 before the first end position

19 and switched off at a second switching point 22 before the second end position 20.

The first switching position 21 and the second switching position 22, as well as the first position 19 and the second end position 20 are clearly defined by the geometric relationships of the gear 3 and the motor 2 and are clearly assigned to the respective positions and switching points via the position sensor 13. On the one hand, this assignment can take place automatically when the drive 1 is first put into operation in production. On the other hand, it is possible to define the first switching point 21 and the second switching point 22 as well as a third switching point 23 and/or a fourth switching point 24 as well as any other switching points at any position of the adjustment path of the output element 4.

This makes it very easy to adapt the electric actuator to a device that is subject to manufacturing tolerances.

The automatic determination of the first switching point 21 and the second switching point 22 takes place in that the motor 2 of the drive 1 is preferably slowly moved in the direction of the respective end position.

When the respective mechanical end stop is reached in the end positions 19 or

20, the motor current increases in a specific manner, is detected by the current monitoring module 17 and communicated to the control module 16 via the feedback 31. The control module 16 stores the position value received from the position sensor 13 via the evaluation module 14 at the moment of the current increase of the motor 2 in the memory module 15, assigned to the respective end position of the adjustment path of the output element 4. The control 5 thus automatically recognizes the first end position 19 and the second end position 20 of the adjustment path of the output element 4. For the automatic determination of the first switching point 21 and the second switching point 22, the position value assigned to the respective end position in the memory module 15 is increased by a certain previously determined or determined value.

·· t

BOEHMERT & B0EHMÖRT * * *
-9-

calculated value is increased or decreased. This automatic setting of the switching points takes place during the production of the drive via a special operating element (not shown). During normal operation with the manual control 6, the motor is switched off at the automatically set switching points 21, 22 before the respective mechanical end stop is reached. This takes place because the control module 16 constantly compares the current actual value of the position sensor 13 with the stored position value for the respective switching points 21, 22 and switches the motor off if they are the same.

The manual setting of the switching points 21, 22 can be carried out by operating a second actuating element 8 in the manual control 6 or a third actuating element 9 via an actuator 10, also in the manual control 6, or a fourth actuating element 11 on the control 5 when the respective positions of the locking path of the output element 4 are reached. By operating one or more of these actuating elements 8, 9, 11, the respective actual value of the position sensor 13 in the control module 16 is linked to the first switching point 21 and the second switching point 22, with this link being stored in the memory module 15.

Instead of the second actuating element 8 or the third actuating element 9, a certain predetermined actuating sequence of the first actuating elements 7, 7' can also be used.

In a preferred embodiment, the third actuating element 9 is a magnetic field-sensitive switching element which is activated by a magnet applied from the outside, referred to here as actuator 10.

A further exemplary embodiment provides for arranging a fifth actuating element 12 for determining the switching points on the motor 2.

¹ &igr;

BOEHMERT & BOEHMOERT ' * *

-10-

The signal transmission of this fifth actuating element 12 takes place via the evaluation module 14 to the control module 16.

An acknowledgement tone or an acknowledgement signal for the successfully stored switching points in the memory module 15 is sent via the signaling module 18. The signaling module 18 can be designed, for example, as a light indicator on the control unit 5 and/or on the manual control unit 6. The signaling module 18 can also be an acoustic signaling device that signals the corresponding acknowledgement message, for example, by means of a specific tone sequence or just by a click, for example of a motor relay.

The position sensor 13 can be, for example, an incremental rotary encoder. However, the invention is not limited to the embodiment described. Both incremental and absolute rotary and displacement sensors are conceivable.

Furthermore, drives with a linearly adjustable drive element 4, as described here, as well as with a rotatingly adjustable output element can be used. In this case, the mechanical end stops are determined, for example, by the mechanics of the furniture being driven.

In the case of a rotary adjustable drive element, position sensors 13 in the form of multi-turn potentiometers can also be used. This creates an electromotive adjustment drive for furniture which can be easily and advantageously equipped with variable end stop points, regardless of the length of the adjustment path or the size of the angle of rotation and regardless of manufacturing tolerances, by entering a control switching point at the respective positions of the adjustment path or the angle of rotation of the output element at the push of a button.

j. &igr; -5JW..{ j,·:

BOEHMERT & BOEHMEKT * * *

-11-

The controller 5 can be equipped with a control module 16 which is designed as a microprocessor. Known non-volatile memory modules can be used as the memory module 15.

Furthermore, it is possible for the hand control 6 to communicate with the control 5 wirelessly, for example via an infrared or radio link.

The external power supply 29 can also be equipped with a switching device with an auxiliary voltage source for separation from a mains connection.

A further embodiment provides that the control module 16 does not immediately switch off the motor 2 when the first switching point 21 is reached before the first end position 19 and when the second switching point 22 is reached before the second end position 20, but reduces its rotational speed until it has come to a standstill in a short time (soft stop function).

The same function can be carried out when further switching points 23, 24 are reached. It is also conceivable that when additional switching points are reached the motor is not only stopped, but that this switching signal is also used for further control purposes. It is also possible that the motor is not stopped at such switching points, but only a signal is passed on.

In a further embodiment, it is provided that the assignment of the first switching point 21 to the first end position 19 and the assignment of the second switching point 22 to the second end position 20 is not carried out automatically with the help of the current monitoring module 17, but that when the end position 19, 20 is reached, the respective switching point 21, 22 is set at these points by means of an actuating element 8, 9, 11, 12. This is then manually entered by the control module 16.

BOEHMERT & BO'eHMERT* *

A switching point with a predetermined safety distance to the respective end positions 19, 20 is stored in the memory module 15.

Another embodiment provides that the end positions 19, 20 are detected by conventional switches in a known manner. Additional switching points 21, 22 are assigned to these end positions 19, 20. The control module 16 monitors the switching point of the end position 19 and its associated switching point 21 or the switching point of the end position 20 and its associated switching point 22. This makes it very easy to generate several switching signals per end position. In the interests of first-error protection, both switching signals are monitored by the control module 16 and if an error occurs, e.g. a defect in the evaluation module 14 or a defect in a switch assigned to the end positions 19, 20, it is detected in the form of the absence of one of the signals and displayed to the operator.

1 J · ' - ? ^&iacgr;# :· ■ I I. "· drive - 2 List of reference symbols engine 3 transmission 4 Output element 5 steering 6 Manual operation 7.7' first actuating element 8th second actuating element 9 third actuating element 10 Actuator 11 fourth actuating element 12 fifth actuating element 13 Position sensor 14 Evaluation module 15 Memory module 16 Control module 17 Current monitoring module 18 Reporting module 19 first end position 20 second end position 21 first switching point 22 second switching point 23 third switching point 24 fourth switching point 25 Operating connection 26 Motor connection 27 Power supply cable 28 internal power supply 29 external power supply 30 Power supply connection 31 Feedback current monitoring

D10217(H)

Claims (22)

1. Electromotive actuator for low-voltage applications, in particular furniture drive, with at least one motor ( 2 ) with an adjustable and/or rotatable output element ( 4 ), the adjustment path and/or angle of rotation of which has a first end position ( 19 ) and a second end position ( 20 ), with a position sensor ( 13 ), with at least one manual control ( 6 ), with at least one control ( 5 ) and with a power supply ( 28 , 29 ) which has at least one mains-dependent voltage source, or at least one mains-dependent and one mains-independent voltage source, characterized in that between the first end position ( 19 ) and the second end position ( 20 ) of the adjustment path and/or angle of rotation of the output element ( 4 ), a position of the adjustment path and/or angle of rotation of the output element ( 4 ) at or at any desired distance from the first end position ( 19 ) and at least one switching point ( 21 , 22 ) is assigned to each of the two end positions ( 20 ) or at any distance from the second end position ( 20 ), wherein this assignment is designed to be variable. 2. Electromotor actuator according to claim 1, characterized in that the assignment of the switching points ( 21 , 22 ) to the end positions ( 19 , 20 ) in a specific operating state for setting up the drive ( 1 ) takes place automatically. 3. Electromotor actuator according to claim 2, characterized in that for the automatic assignment of the switching points ( 21 , 22 ), a current monitoring module ( 17 ) for detecting the end positions ( 19 , 20 ) by an increase in the motor current when mechanical end stops are reached in the end positions ( 19 , 20 ) of the adjustment path and/or angle of rotation of the output element ( 4 ), an evaluation module ( 14 ) for evaluating the signal of the position sensor ( 13 ), a memory module ( 15 ) for storage and a control module ( 16 ) for controlling the motor ( 2 ) and for assigning the switching points ( 21 , 22 ) to the respective position values and storing them in the memory module ( 15 ) are provided. 4. Electromotive actuator according to claim 1, characterized in that at least one second ( 8 ), third ( 9 ), fourth ( 11 ) or fifth actuating element ( 12 ) is provided for assigning the switching points ( 21 , 22 ) and further switching points ( 23 , 24 ). 5. Electromotor actuator according to claim 4, characterized in that for the assignment of the switching points ( 21 , 22 , 23 , 24 ) an evaluation module ( 14 ) for evaluating the signal of the position sensor ( 13 ), a memory module ( 15 ) for storage and a control module ( 16 ) for controlling the motor ( 2 ) and for assigning the switching points ( 21 , 22 , 23 , 24 ) entered by means of the actuating element ( 8 , 9 , 11 l, 12 ) to the respective position values and storing them in the memory module ( 15 ) are provided. 6. Electromotor actuator according to claim 5, characterized in that when assigning the switching points ( 21 , 22 ) a safety value is automatically checked by the control module ( 16 ) to maintain the distance between the respective switching point ( 21 , 22 ) and the associated end position ( 19 , 20 ) and is added if necessary. 7. Electromotive actuator according to one of claims 1 to 6, characterized in that the second, third, fourth and/or fifth actuating element ( 8 , 9 , 11 , 12 ) is provided for subsequent changes in the assignments of the switching points ( 21 , 22 ) and further switching points ( 23 , 24 ). 8. Electromotive actuator according to one of claims 1 to 7, characterized in that the second ( 8 ) and/or the third actuating element ( 9 ) is arranged in the manual control ( 6 ). 9. Electromotive actuator according to one of claims 1 to 7, characterized in that the fourth actuating element ( 11 ) is arranged on the control ( 5 ) and/or the fifth actuating element ( 12 ) is arranged on the motor ( 2 ). 10. Electromotive actuator according to claim 8, characterized in that the second actuating element ( 8 ) is designed as a button or as a specific button sequence of the first actuating elements ( 7 , 7 '). 11. Electromotive actuator according to claim 8, characterized in that the third actuating element ( 9 ) is a sensor that can be activated by an externally applicable actuator ( 10 ). 12. Electromotive actuator according to claim 11, characterized in that the third actuating element ( 9 ) is a Hall sensor and the actuator ( 10 ) is a magnetic field. 13. Electromotor actuator according to one of claims 1 to 12, characterized in that the control module ( 16 ) provides a signal for further processing at an interface in a suitable form when the switching points ( 21 , 22 , 23 , 24 ) are reached. 14. Electromotor actuator according to claim 13, characterized in that the signal influences the motor ( 2 ) for further processing. 15. Electromotor actuator according to claim 14, characterized in that the control module ( 16 ) switches off the motor ( 2 ) by means of a soft stop function when the switching points ( 21 , 22 , 23 , 24 ) are reached. 16. Electromotive actuator according to one of claims 1 to 15, characterized in that in the event of a subsequent change in the switching points ( 21 , 22 , 23 , 24 ), these are deleted by means of an additional actuating element and/or a manual maintenance control. 17. Electromotor actuator according to one of claims 1 to 16, characterized in that the control ( 5 ) has a signaling module ( 18 ). 18. Electromotor actuator according to claim 17, characterized in that the signaling module ( 18 ) is an optical display and/or an acoustic detector. 19. Electromotor actuator according to claim 18, characterized in that the acoustic signal of the signaling module ( 18 ) is formed by the clicking of a relay. 20. Electromotive actuator according to one or more of claims 1 to 19, characterized in that the end position ( 19 , 20 ) and/or further intermediate positions are detected by conventional switching means and additional switching points are assigned to these and other positions. 21. Electromotor actuator according to claim 20, characterized in that several switching signals per switching point are supplied by the control unit ( 16 ). 22. Electromotive actuator according to one or more of claims 1 to 21, characterized in that the power supply ( 28 , 29 ) is connected to a switching device for isolating the power supply ( 28 , 29 ) from a mains connection.