DE20314216U1 - Electromotive actuator with control unit for intermediate position - Google Patents

Abstract

Electromotive Adjusting drive, especially for Furniture, with an output element (12), the end and intermediate layers by the adjusting drive influencing limit switch (13, 14) and at least an intermediate switch (15) are fixed, and with a control unit (1) with intermediate position control, characterized in that the intermediate switch (15) has a changeover contact, and in that the control unit (1) for the intermediate position control at least one bridge switch (22) and at least one control block (23).

Description

The The invention relates to an electromotive adjusting drive, in particular for furniture, with an output element whose end and intermediate layers by the adjustment determining limit switch and at least one intermediate switch are, as well as with a control unit with intermediate position control.

electromotive Adjustment drives for Furniture is in many different versions known. They are used, for example, to backrests and foot parts of armchairs in their inclination to disguise. Come for this Both linear drives and rotary drives are used. Both is common that theirs Travel distances or angles are limited by limit switches. These Limit switches are controlled by actuators, which are arranged on the respec gene output members, upon reaching pressed the respective end position and can so the power supply to the respective motor directly or indirectly interrupt.

The Operation of such drives via operating buttons, which for example, are arranged on a so-called manual control. Has the drive reaches an end position, so it is no longer possible with push the motor in the same direction to the respective operating button to proceed. There is only one procedure in the opposite Direction possible.

It is known for certain furniture, such as B. in a stand-up chair, an additional limit between to arrange the two end positions. This is useful because a stand-up chair in the one end position like a couch extended is and in the other end position a high-driven oblique seat as Stand up assistance forms. The intermediate position is the normal one in this case Sitting position, which is a reproducible position of the chair should. Now, such an adjustment with intermediate position from the direction of one of the two end positions towards the Move seat position, so holds the drive automatically in the sitting position, even if the operating button continue pressed remains. After releasing this control button, it is possible to adjust the adjustment to move in any direction.

This function is realized in a known embodiment by means of a relay circuit in which special relays, so-called bistable relays, are used. Another solution describes DE 298 20 233 U1 in which an additional operating button on the manual control is arranged for the intermediate position. A disadvantage of both versions, that due to the necessary relay control additional and expensive components are used, which additionally also disadvantageously occupy space. Since the field of application of such drives comprises furniture, in particular seating furniture, in which primarily a low installation space and a low price are required, the use of the known solutions is not possible or uneconomical. In the known embodiments described above, another disadvantage is that the control of the Verstellan drive, which is often designed as a relay control, requires its own housing. To eliminate this extra space, there are known solutions without relay control, in which the motor current is switched directly from the manual control. A disadvantage of these solutions, however, is that they have no intermediate switch.

The The object of the invention is therefore an electromotive Adjusting drive, especially for Furniture, to create, which no longer has the disadvantages mentioned above and other advantages over the state of the art offers.

These Task is inventively characterized solved, that the Intermediate switch has a changeover contact, and that the control unit for the intermediate position control at least one bridge switch and at least one control block.

advantageous Further developments of the invention are contained in the subclaims.

A preferred embodiment the invention provides that the Intermediate position control on a control unit within the drive housing the electromotive adjusting drive is arranged. At this Control unit are the connections for the motor, the limit switches and the intermediate switch. Also can be plugged in from the outside: a control unit, a power supply and optionally at least one additional auxiliary drive.

The intermediate position control consists of a bridge switch and a control block, which advantageously affects the bridge switch so that it is possible in the simplest advantageous manner to approach the intermediate position with the elecromotor adjustment drive from each direction. In this case, the operating button for the adjusting motor remain depressed, the adjusting motor is automatically switched off in the intermediate position. An additional operating button for the intermediate position is advantageously not required. The intermediate switch is a changeover switch whose one contact path, which is closed during normal operation of the drive, is electrically bridged by the bridge switch. The bridge switch is in egg ner preferred embodiment, a semiconductor device, preferably, a transistor. In the bridge switch can continue to be arranged a current limiting element.

In a further embodiment The invention is in the bridge switch arranged a sensor element, which, for example, a temperature-sensitive Resistance, a so-called PTC type can be. Thus is in easier Way a monitoring of the bridge switch for example, in terms of overload allows.

Of the bridge switch has a control input connected to an output of the control block is. About here can the bridge switch dependent on from the operating conditions of the electromotive adjusting drive Advantageously be influenced by the control block specifically.

This is thereby possible that the Control block a first Schalälälleiter and a second Schalthalbleitleiter and at least one input for a first polling connection and an entrance for has a second query connection. The two Schalthalbleiter are in a known manner to a so-called flip-flop, a electronic switching arrangement, formed. The influence of this electronic switch is realized on the one hand by the first query connection, which the switching state of the controls of the manual control signaled to the control block, and on the other hand through the second Polling connection, which the state of the intermediate switch the Control block signals. This makes it possible that when operated manual operation of the engine is switched off when reaching the intermediate switch, wherein the bridge switch through the control block is locked due to these operating conditions. If now the operating button is released, the operating conditions change, which are signaled to the control block and the control block gives an output signal to the bridge switch, which thereby is turned on. Because the bridge switch parallel to the in this situation switched off intermediate switch is, can now by another operation of any operating button the adjusting drive in a desired Move adjustment direction.

In the embodiment, in which the sensor element is a temperature sensor, for example this temperature sensor, which is preferably a PTC resistor, in the circuit of Control blocks are included, the output signal of the Control block advantageously can be additionally influenced. For example, if the variable displacement motor is blocked in the intermediate position or overloaded by too high a load, this recognizes the Control block over the sensor element and thus the bridge switch back in one open further execution, so that the Engine is stopped again.

In a further embodiment is in the direction of travel the adjusting drive another change-over switch in front of the intermediate switch, which before reaching the intermediate switch of the output element the adjusting drive is actuated. This changeover switch switches in this situation, a current limiting resistor in the motor line, which is advantageously achieved that the adjustment drive is decelerated before reaching the intermediate switch and slowly continues until it is switched off by the intermediate switch. This can be in one direction as well as in both directions respectively. Preferably, this so-called braking resistor is through the already existing current limiting element of the bridge switch educated.

By the use of transistors or suitable Schalälbleitern for the bridge switch and the control block as well as a minimum amount of electronic Components, it is possible a particularly compact and economical adjustment to create. By using the above-described current limiting element is, for example, an advantageous monitoring of the motor starting current possible in conjunction with a suitable sensor element.

The Control unit within the motor housing of the electro-motor Adjustment drive also includes known protective elements, for example against surges, which thus the use of semiconductor devices for these Make application unproblematic.

The Intermediate position control with bridge switch and control block can for a variety of drives are used, not just for the execution, the described here.

It is still possible several intermediate positions by a respective intermediate switch with bridge switch and control block to arrange. Also, the number of auxiliary drives not limited to one.

The switching semiconductors of the control block are charged only with a low switching current. Therefore, they can be used in a particularly small design. Since the switching semiconductor of the bridge switch conducts the motor current only for a short time, this semiconductor can also be correspondingly small in its dimensioning. It can also be an integrated protection element as a standalone ge include temperature protection circuit.

So is an electromotive actuator for use in furniture with special restrictive Conditions for created the installation space and cost-effectiveness.

Of course, the application of the invention in connection with a double intermediate switch, as in
DE 295 04 987 U1 described, possible to eliminate a switching hysteresis due to a correspondingly long actuator.

Further Details of the invention are described in the drawings with reference to a embodiment described. It shows:

1 a schematic representation of an exemplary electric motor drive system with an intermediate position;

2 a switching example, partially in block diagram, an intermediate position control; and

3 the switching example according to 2 in an exemplary embodiment.

In the 1 is an exemplary electric motor drive system with two variable displacement drives shown schematically. A drive 2 , a so-called linear drive, includes a motor 11 , which via known transmission types an output element 12 moved back and forth in the direction of its longitudinal axis. The output element 12 has actuating means in a known manner 30 , z. As a switching cam on, with which limit switch 13 . 14 . 15 in the extended and in the retracted position of the output element 12 be operated. In the illustrated example forms a first limit switch 13 the extended end position and a second limit switch 14 the retracted end position. An intermediate switch 15 is at the position of an intermediate position.

Furthermore, the drive includes 2 a control unit 1 , on which a service 8th , a supply connection 9 and in this embodiment, an auxiliary terminal 10 are arranged. With the operation manual 8th is a control unit 4 with controls 16 . 17 . 18 . 19 connected. A power supply 5 on one side with a power cord 6 is connected to the electrical supply network is via another connection cable to the supply connection 9 the control unit 1 connected. At the additional connection 10 is via a connection cable 7 an auxiliary drive 3 connected, whose construction except for a connection unit 31 the drive 2 equivalent.

The operating instructions 8th , Supply connection 9 and the auxiliary connection 10 are usually designed as connectors, but may also be all or even partially designed as a fixed connection.

The control unit 1 preferably comprises a printed circuit board on which the terminals 8th . 9 . 10 with the engine 11 and the limit switches 13 . 14 . 15 electrically connected via conductor tracks. Furthermore, on the control unit 1 an intermediate position control and further known electrical and / or electronic components arranged, which are explained in more detail below.

The power supply 5 For example, is provided with a transformer, a rectification and a filter capacitor, so that the connection line between the power supply 5 and supply connection 9 at the drive 2 a harmless low DC voltage leads.

Applying the motor 11 with the supply voltage of the power supply 5 takes place in that by pressing a first control element 16 its switching contacts 32 on the control unit 4 the motor 11 in a certain polarity with the DC voltage of the power supply 5 is applied and rotates in a certain direction, wherein the output element 12 of the drive 2 retracts or retracts. By releasing the first operating element 16 the power supply to the engine 11 interrupted and the engine 11 stops. By pressing a second control element 17 on the control unit 4 , becomes the engine 11 with reverse polarity of the DC voltage of the power supply 5 applied, wherein it changes its direction of rotation, and the output element 12 in the opposite direction.

The switching contacts 32 can also be contacts of a relay.

A third operating element 18 and a fourth operating element 19 on the control unit are the auxiliary drive 3 assigned. Because the auxiliary drive 3 in its function to the drive 2 corresponds, the same reference numerals apply to identical components.

When operating a control element 16 . 17 (This also applies to the auxiliary drive 3 ) the motor moves 11 the output element 12 of the drive 2 in a certain direction until the actuating means 30 which is z. B. on the output element 12 is one of the limit switches 13 . 14 . 15 actuated. By pressing the first limit switch 13 or the second limit switch 14 is determined by the respective limit switch 13 . 14 the power supply to the engine 11 interrupted. The engine can only after reaching such an end position in the entgegenge set course, as is known.

Will the intermediate switch 15 from the actuating means 30 pressed, then the engine 11 also stopped. This is necessary, for example, in adjustable rest chairs to achieve a certain seat position to be reproduced. After releasing the previously operated control element 16 or 17 it is possible by pressing any control element 16 . 17 drive the drive in any direction. This function of the intermediate position control will be described below with reference to 2 explained in more detail.

2 shows a switching example of the control unit 1 with intermediate position control partly in block representation and with usual electrical / electronic switching symbols. Here, the same reference numerals of 1 for the same components.

The symbols for the controls 16 . 17 , the limit switch 13 . 14 and for the intermediate switch 15 are all shown in a non-actuated position.

On the control unit 1 is the supply connection 9 , which is shown here with the poles plus and minus. The supply connection 9 is with the operating instructions 8th connected to which the operator unit 4 with the controls 16 and 17 and their switch contacts 32 connected in a known manner and interconnected. Also, the port configuration of the engine 11 with the limit switches 13 and 14 and bridge diodes 20 known.

The bridge diodes 20 in a likewise known manner ensure that at an actuated limit switch 13 . 14 An actuation of the engine is only possible in the opposite direction.

The intermediate position controller consists of the intermediate switch 15 , a bridge switch 22 and a control block 23 ,

In the current path of the positive lead of the supply connection 9 is the intermediate switch 15 arranged. The intermediate switch 15 is a so-called changeover switch with a common terminal g, a normally closed contact nc and a normally open contact no.

The intermediate switch 15 is through the bridge switch 22 bridged with the terminals x, y. The bridge switch 22 has a control terminal z, which with the control block 23 via a control connection 29 is connected to the connection point b. The control block 23 is to the supply connection 9 connected, he is still standing with the switch contacts 32 via at least one first query connection 27 at its connection point a in electrical connection, and with the no contact of the intermediate switch 15 via a second query connection 28 with its connection c in electrical connection.

When operating the intermediate switch 15 the normally closed contact opens nc and cuts the circuit to the motor 11 , which is thus stopped. At the same time the normally open contact no of the intermediate switch 15 closed and stands over the second query connection 28 with the control block 23 now in electrical connection. The electrical boundary conditions at the switch contacts 32 be through the first query connection 27 the control block 23 communicated. The control block prepares the processing of this information 23 a control signal which at its terminal b via the control connection 29 the bridge switch 22 is transmitted electrically at its connection point z.

As long as the previously operated control element 16 . 17 is still pressed, causes the signal at the connection point b of the control block, a blockage of the bridge switch 22 , so that the motor is still not supplied with supply voltage. When you release the previously operated control element 16 . 17 The electrical boundary conditions at the switch contacts change 32 which is via the first query connection 27 the control block 23 is communicated. The control block 23 now changes its signal at its terminal b, causing the bridge switch 22 over the control connection 29 is turned on to its control input z. When re-pressing a control element 16 . 17 bridges the now conductive bridge switch 22 the open, normally closed contact nc of the intermediate switch 15 and thus leaves the engine 11 start. Once the engine is running, the output element 12 Continue, so that the intermediate switch 15 is no longer actuated and closes the normally closed contact nc again. At this moment, the normally open contact is no of the intermediate switch 15 opened again and signals this state via the second query connection 28 the control block 23 over the connection c.

Only in this time of engine startup, until the intermediate switch 15 is no longer actuated, the motor starting current flows through the bridge switch 22 , whereby this can be advantageously sized small.

It is particularly advantageous that the bridge switch 22 and the control block 23 work together on the control unit 1 and thus within the drive 2 are located. An additional control unit with a separate external control housing is not required.

In this switching example the 2 the entire motor current is directly via the operating unit 4 directed. It is of course possible that the switching contacts 32 the controls 16 . 17 which are shown here as a change contacts in a known manner, can be replaced by relay contacts. This is provided for example in another embodiment.

The switching example of 2 will be in the 3 explained in more detail with reference to an exemplary circuit.

In 3 there is the bridge switch 22 from a bridge semiconductor 24 , which in this case may be a transistor. Its connection x, is with the plus line of the supply connection 9 connected. Another terminal of the transistor is connected via a current limiting element R1, via the terminal y to the normally closed contact nc of the intermediate switch 15 connected. The connection z of the bridge switch 22 is a control input of the transistor.

The control block 23 becomes from a first Schalthalbbleiter 25 and a second switching semiconductor 26 formed, in this embodiment, the Schalthalbleiter 25 . 26 Transistors are. These two transistors are interconnected in a known manner so that, for example, results in a so-called flip-flop. This flip-flop has a control input c, which the second query connection 28 to the normally open contact no of the intermediate switch 15 forms. The first query connection 27 consists in this embodiment of two lines connected to the switch contacts 32 are connected. These first two query connections 27 are via connection points a, a 'with the control block 23 connected.

Furthermore, the control block 23 a connection point d, which is in communication with a sensor element R2, which may be a PTC resistor, for example, in direct thermal operative connection with the current limiting element R1 or the bridge semiconductor 24 stands. Thus, a particularly advantageous monitoring of the motor current, and / or the bridge semiconductor 24 when starting the engine 11 possible from the intermediate position. This will cause the control block 23 influenced so that, for example, at a high motor current of the bridge semiconductor 24 over the control connection 29 is locked again and thus interrupts the motor current.

The function of the control block 23 is described below. An actuation of the first operating element 16 turns off the engine 11 by means of the switching contact 32 one. When reaching the intermediate switch 15 through the actuator 30 this is switched by this. As a result, the closed contact nc of the intermediate switch 15 open, with the engine 11 is turned off. At the same time, the open contact no of the intermediate switch 15 closed. This preserves the second query connection 28 positive potential from the supply connection 9 , which now at the connection point c of the control block 23 pending. As long as the first control element 16 is actuated, lies at the switch contact 32 negative potential, at the switching contact 32 of the second operating element 17 on the other hand lies positive potential of the supply connection 9 as is known. The two-wire first polling connection 27 sets the potential occurring at the respective switching contact to the control block 23 via its connection points a, a '. While the engine is running 11 is the second switching semiconductor 26 switched through and the first Schalthalhalbleitleiter 25 blocked. It follows that the control connection 29 a potential across the connection point z to the base of the bridge semiconductor 24 sets, which locks it, and thus the engine 11 when reaching the intermediate switch 15 is switched off when switching.

The two Schalthalbleiter 25 and 26 of the control block 23 lock each other. Thus, the first Schalälbleiter 25 not be switched through.

Only when the previously operated first control element 16 is released again, and thus to the connection points a, a 'of the control block 23 this state is transmitted, locks the second Schalälbleiter 26 , and the first switching semiconductor 25 is switched through, because at this time the intermediate switch 15 is still switched and via its closed no-contact positive potential on the second query connection 28 located at the connection point c. The switching through of the first Schalthalhalbbleiters 25 causes the potential on the control link 29 changes so that the bridge semiconductor 24 is switched through. Because the bridge switch 22 represents a conductive connection and the intermediate switch 15 bridged, can now by pressing a control element 16 . 17 the motor 11 restart in the desired direction of rotation.

In the event that the actuating means 30 no short switching cam, but a longer switching nose is how out DE 295 04 987 U1 is known, two intermediate switches 15 provided, which are interconnected in parallel. In this case, the actuating means must both intermediate switch 15 Press for the drive to move to the intermediate position tion stops.

In a further embodiment, the adjustment speed of the engine 11 reduced shortly before reaching the intermediate position. This is achieved in an advantageous manner in that between the nc contact of the intermediate switch 15 and the operating instructions 8th another changeover switch like the intermediate switch 15 is used. This changeover switch is before reaching the intermediate switch 15 from the actuating means 30 actuates and switches via its normally open contact a series resistor or current limiting element, which may advantageously be the already existing current limiting element R1, in the motor current path. This ensures that the engine 11 advantageously before reaching the intermediate position runs at a lower speed.

In the presence of an additional drive 3 this is about the additional connection 10 to the control unit 1 connected, the control unit 1 for the auxiliary drive 3 a second bridge switch 22 and a second control block 23 may have, if the auxiliary drive 3 also has an intermediate switch.

The bridge switch 22 and the control block 23 can also be used for other drive configurations, their use is not limited to the case described here. Furthermore, the embodiment described here with transistors as a bridge semiconductor 24 and switching semiconductors 25 . 26 consist of other components. It is understood that the circuit design further protection components against high voltage pulses of the motor 11 etc. has.

The Embodiment described here is not limited to linear drives, the application can, of course, as is easy to understand, for example, for rotary drives with Limit switches are used.

1

control unit

2

drive

3

accessory drive

4

operating unit

5

power supply

6

power cable

7

connection cable

8th

operation connection

9

supply terminal

10

Second line

11

engine

12

output element

13

first limit switch

14

second limit switch

15

between switch

16

first operating element

17

second operating element

18

third operating element

19

fourth operating element

20

bridge diode

22

bridge switch

23

control block

24

Bridge Semiconductor

25

first Switching semiconductor

26

second Switching semiconductor

27

first Prompt Circuit

28

second Prompt Circuit

29

control connection

30

actuating means

31

connection unit

32

switch contacts

a-d, x-z

connection points

G, nc, no

contacts

0, I

switch positions

R1

Current limiting element

R2

sensor element

Claims (11)

Electromotive adjusting drive, in particular for furniture, with an output element ( 12 ), whose end and intermediate layers by the adjusting drive-influencing limit switch ( 13 . 14 ) and at least one intermediate switch ( 15 ) and a control unit ( 1 ) with intermediate position control, characterized in that the intermediate switch ( 15 ) has a changeover contact, and that the control unit ( 1 ) for the intermediate position control at least one bridge switch ( 22 ) and at least one control block ( 23 ) having. Electromotive adjusting drive according to claim 1, characterized in that the bridge switch ( 22 ) to at least one contact path of the intermediate switch ( 15 ) is electrically connected in parallel. Electromotive adjusting drive according to claim 2, characterized in that the bridge switch ( 22 ) has a control input (z), which with an output (b) of the control block ( 23 ) is electrically connected, Electromotive adjusting drive according to Claim 3, characterized in that the bridge switch ( 22 ) a bridge semiconductor ( 24 ) having. Electromotive adjusting drive according to claim 3 or 4, characterized in that the bridge switch ( 22 ) has at least one current limiting element (R1). Electromotive adjusting drive according to one or more of claims 1 to 5, characterized in that the control block ( 23 ) a first Schalthalhalbbleiter ( 25 ) and a second switching semiconductor ( 26 ), at least one input (a) for at least one first polling connection ( 27 ) and an input (c) for a second query connection ( 28 ) having. Electromotive adjusting drive according to Claim 6, characterized in that the switching semiconductors ( 25 . 26 ) Are transistors, and that the first query connection ( 27 ) with switch contacts ( 32 ) of operating elements ( 16 . 17 ) or is electrically connected by other switching means, and that the second query connection ( 28 ) with a contact path of the intermediate switch ( 15 ) is electrically connected. Electromotive adjusting drive according to claim 6 or 7, characterized in that the bridge switch ( 22 ) has a sensor element (R2) which detects the output signal of the control block (R2) 23 ). Electromotive adjusting drive according to one or more of claims 1 to 8, characterized in that in the adjustment direction of the drive ( 2 . 3 ) in front of the intermediate switch ( 15 ) at least one further switch with changeover contact is arranged at a distance which, when actuated, forms a braking resistor in the current-carrying line of the motor ( 11 ) switches. Electromotive adjusting drive according to claim 9, characterized in that the Braking resistor formed by the current limiting element (R1) becomes. Electromotive adjusting drive according to one or more of claims 1 to 10, characterized in that when using two intermediate switches ( 15 ) for hysteresis influencing of an actuating means ( 30 ) these two intermediate switches ( 15 ) are connected in parallel to each other.