Positioning arrangement for moving an object that is to be positioned

Abstract

A positioning arrangement is provided for moving an object that is to be positioned (9) with at least one positioning axis (11), wherein at least two electric motors (6) for moving the object that is to be positioned (9) are assigned to at least one positioning axis (11). Each electric motor (6) has its own separate control circuit (2), wherein the control circuits (2) are designed in each case to receive adjustment requests for a positioning direction. The control circuits (2) are furthermore designed in each case to evaluate the adjustment request and the electric motors (6) are interconnected via a communication interface (13). The adjustment requests and the movement commands to control the electric motors (6) can be exchanged via this communication interface (13).

Claims

1. A positioning arrangement for moving an object that is to be positioned (9) with at least one positioning axis (11), comprising at least two electric motors (6) for moving the object that is to be positioned (9), which are assigned to the at least one positioning axis (11), each said electric motor (6) has a separate control circuit (2) of its own, the control circuits (2) are configured in each case to: (A) receive adjustment requests for a positioning direction, and (B) evaluate the adjustment request, and the electric motors (6) are interconnected via a communication interface (13) via which the adjustment requests and movement commands to control the electric motors (6) are exchangeable.

2. The positioning arrangement according to claim 1, wherein the control circuits (2) are connected to a common switch control circuit (17) and a switch control circuit (17) transmits the adjustment requests to the control circuits (2) of the electric motors (6).

3. The positioning arrangement according to claim 2, wherein the switch control circuit (17) is connected to one or more actuation elements (3), the switch control circuit (17) transmits an adjustment request to the respective control circuit (2) following actuation of one of the actuation elements (3).

4. The positioning arrangement according to claim 1, wherein the control circuits (2) are connected in each case directly to an actuation element (3), and the actuation element (3) transmits the adjustment request to the respective control circuit (2).

5. The positioning arrangement according to claim 4, wherein exactly one actuation element (3) is assigned to each positioning direction.

6. The positioning arrangement according to claim 1, wherein the communication interface (13) is a bus interface or a PWM interface.

7. The positioning arrangement according to claim 6, wherein the communication interface (13) is a bus interface and the first electric motor (6, M1) is configured as a master which can poll and receive the adjustment requests from actuation elements (3) of a second electric motor (6, M2) and transmits movement commands via the communication interface (13).

8. A method for operating a positioning arrangement according to claim 6, wherein the communication interface (13) is a bus interface, and a first one of the electric motors (6; M1, M2) is configured as a master, the method, following an actuation of the actuation elements, comprises the following steps: determining the adjustment requests present on all of the electric motors (6; M1, M2) by the first electric motor (6; M1) configured as the master, and checking of a validity of the determined adjustment requests by the first electric motor (6; M1) configured as the master, and transmitting at least one movement command from the first electric motor (6; M1) configured as the master to all other ones of the electric motors (6; M2) connected via the communication interface (13) if a valid adjustment request is present.

9. The method according to claim 8, wherein, following reception of the at least one movement command, all of the electric motors (6; M1, M2) in the group move simultaneously and synchronously in a positioning direction requested by the actuation element (3).

10. The method according to claim 8, wherein a determination of all of the adjustment requests present on the electric motors (6; M1, M2) by the first electric motor (6; M1) configured as the master comprises the following steps: transmitting a query to determine whether an adjustment request is present, from the control circuit (2) of the first electric motor (6; M1) configured as the master to all control circuits the other electric motors (6; M2), and forwarding of the adjustment requests registered by the control circuits (2) of the other electric motors (6; M2) to the control circuit (2) of the electric motor (6; M1) configured as the master.

11. The positioning arrangement according to claim 1, wherein the communication interface (13) is designed as a PWM interface.

12. The positioning arrangement according to claim 1, wherein status information of the electric motors (6) is exchanged between the control circuits (2) via the communication interface (13).

13. The positioning arrangement according to claim 12, wherein the status information comprises at least one of the following information elements: a fault message, a position datum, an adjustment path travelled, a phase current of an electric motor (6), a temperature, an adjustment speed or a supply voltage of an electric motor (6).

14. The positioning arrangement according to claim 1, wherein the electric motors (6) are brushless DC motors.

15. A positioning arrangement for opening and closing a convertible top (9), comprising an electric motor (6) on each side of the top, with a first actuation element (4) for opening (10) the top (9) which is connected to a first one of the electric motors (6; M1) and a second actuation element (5) for closing (12) the top (9) which is connected to a second one of the electric motors (6; M2), wherein the two electric motors (6; M1, M2) are interconnected via a LIN connection (14) via which switching positions of the two actuation elements (4, 5) for a validity check and movement commands are exchanged between the electric motors (6; M1, M2).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention is explained in detail below on the basis of a preferred design with reference to the attached drawings.

(2) In the drawings:

(3) FIG. 1: shows a block diagram of a positioning arrangement according to the prior art,

(4) FIG. 2: shows a positioning arrangement according to the invention, and

(5) FIG. 3: shows a block diagram of the positioning arrangement shown in FIG. 2, and

(6) FIG. 4: shows a block diagram of an alternative design of the positioning arrangement from FIG. 2.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

(7) FIG. 1 shows a block diagram of a positioning arrangement 1 according to the prior art with a central control circuit 2 to which two actuation elements 3 are connected. Each actuation element 3 generates an adjustment request for a movement direction of the positioning arrangement 1. In the example, the positioning arrangement 1 is a top drive for the opening and closing of a convertible top (not shown) by means of an electric motor. The first actuation element 4 is therefore for opening the top, the second actuation element 5 for closing it.

(8) For this purpose, the positioning arrangement 1 has two electric motors 6 which, in the example, are designed in each case as single-phase brushless DC motors. Arrangements are similarly known in which the electric motors 6 are designed as three-phase brushless DC motors (BLDC motors). The control circuit 2 also has the motor drivers 7 to control the DC motors or the three motor phases U, V, W of a BLDC motor. The motor windings of the two DC motors shown are connected to the voltage signals P and M provided in each case by the motor drivers 7. Similarly, in the case of three-phase BLDC motors, the phase windings are connected in each case to the corresponding motor driver 7.

(9) The electric motors 6 additionally have position sensors 8 via which the control circuit 2 can define the absolute position of the electric motors.

(10) The adjustment requests from the actuation element 3 are checked for validity in the control circuit 2 and are converted into movement commands to control the two electric motors 6.

(11) An adjustment request is valid only if only one actuation element 3 is actuated in each case. In the example, this means that the top cannot be simultaneously opened and closed. If the two actuation elements 4 and 5 are actuated simultaneously, either no movement command can be generated, or one positioning direction can be preferred. The top can, for example, then be closed.

(12) In the case of a valid adjustment request, the two electric motors 6 are controlled synchronously, which is also guaranteed via the position data of the position sensors. It can be ensured by a synchronous control that the object that is to be positioned is not tilted and damaged.

(13) On the whole, an elaborate cabling is required in this positioning arrangement, as a result of which the arrangement is expensive and prone to faults.

(14) FIG. 2 shows an example of a positioning arrangement 1 according to the invention for moving an object that is to be positioned 9. The object that is to be positioned 9 is a convertible top in this example also. For this purpose, the positioning arrangement 1 has two electric motors 6 which are similarly designed as BLDC motors. Each control circuit 2 has a motor driver 7 which is connected to the motor phases U, V, W and generates the AC voltages required for operation. The motor driver 7 may, for example, have an inverter with a full-bridge circuit for this purpose. The electric motors 6 can move the object that is to be positioned 9 in two positioning directions 10 and 12 along a positioning axis 11.

(15) A block diagram of the positioning arrangement is shown in FIG. 3. According to the invention, each electric motor 6 now has a control circuit 2 which also contains the motor driver 7 to control the motor phases. Each electric motor 6 is furthermore connected via a control line 18 to an actuation element 3. The first electric motor M1 is connected to the first actuation element 4 to open 10 the top 9, the second electric motor M2 is connected to the second actuation element 5 to close 12 the top 9.

(16) The two electric motors 6 are furthermore connected to an operating voltage source 16 which is not specified in detail and is irrelevant to the invention.

(17) So that the two electric motors 6 can be controlled synchronously with an adjustment request from one of the actuation elements 3, the two electric motors 6 additionally have a LIN interface 13. The LIN interfaces 13 of the two electric motors 6 are interconnected via a LIN connection 14.

(18) The figure furthermore shows a PC 15 which is similarly connected via the LIN connection 14 to the LIN interfaces 13 of the two electric motors 6. However, the PC 15 is required only for the one-off configuration of the LIN interfaces 13 of the two electric motors 6. In normal operation, it is not necessary. A different suitable configuration device can also be used instead of the PC 15.

(19) In the example, the first electric motor M1 is configured as the master. This means that only the motor M1 can transmit movement commands. The second electric motor M2 is configured as a receiver.

(20) The positioning arrangement 1 is operated, for example, according to the following method.

(21) If the first actuation element 4 is actuated to open 10 the top 9, the corresponding adjustment request is registered in the control circuit 2 of the first motor M1. The motor M1 then polls the motor M2 via the LIN interface 13 for the presence of an adjustment request by actuating the second actuation element 5. From the two adjustment requests, it is determined in the control circuit 2 of the first motor M1 whether the top 9 is allowed to be opened. Further sensor values, for example position sensors of the top or other sensor values which do not, however, play an essential role in the invention, can be taken into account for this decision.

(22) If the second actuation element 5 is not actuated in this case and all other possible conditions are also fulfilled, the adjustment request is valid and the top 9 can be opened. To do this, a movement command is transmitted via the LIN interface 13 to the motor M2 so that the two motors M1 and M2 are moved synchronously in the open positioning direction 10.

(23) If the second actuation element 5 is actuated, the second motor M2 transmits the adjustment request to the master M1. The master M1 then also checks the adjustment request from the first switch 4 and again determines the validity of the adjustment request here also and transmits the movement command accordingly to close 12 the top 9.

(24) However, following the reception of a movement command, the electric motors 6 are controlled autonomously by the control circuit 2 of the respective electric motor 6. No position information is exchanged between the two electric motors 6 via the LIN interface 13. The position data may, for example, comprise the signals of one or more all sensors or may be derived therefrom. It can similarly be provided that the position data are determined without sensors. In order to guarantee a synchronous movement of the electric motors 6, the movement command may, for example, contain a final position and a speed or a speed and a movement duration. A speed may also be predefined, so that the electric motor is started simply by a start movement command and is operated until a stop movement command. There are numerous other operating modes which may be advantageous according to the application. The invention is therefore in no way restricted to one of the aforementioned operating modes.

(25) As an alternative to the second electric motor M2 transmitting its present adjustment requests, the master M1 can also poll the second motor M2 for the presence of an adjustment request generated by the second actuation element 5 (polling). The control circuit 2 of the second electric motor M2 becomes simpler as a result, since it only has to respond to queries and does not have to actively transmit. However, depending on the polling interval, the response time may be long after which an actuation of the second actuation element 5 is detected.

(26) In a further design of the invention, it may be provided, for example, that the adjustment request from the second actuation element 5 is mapped at regular intervals on the LIN interface 13 so that the query can be dispensed with and the LIN interface 13 can be directly read in the master. Movement commands can then be transmitted only in the gaps between these intervals.

(27) Numerous further variants are conceivable here also, and for this reason the invention is not intended to be restricted here either to one of the aforementioned options. In particular, it may also be provided in other designs of the invention that the adjustment requests from the actuation element 3 are received by a switch control circuit and the switch control circuit 17 forwards corresponding adjustment requests to the control circuits 2 of the electric motors.

(28) FIG. 4 shows an example of an alternative design of a positioning arrangement 1 according to the invention for moving an object that is to be positioned 9. In comparison with the positioning arrangement shown in FIG. 3, an additional switch control circuit 17 is provided here which is connected via control lines 19 to the actuation element 3. An adjustment request triggered through actuation of an actuation element 3 is then registered by the switch control circuit 17. The switch control circuit 17 is in turn connected via control lines 18 to the control circuits 2 of the electric motors 6 and is designed to transmit a corresponding adjustment request to the respective control circuit 2 or to forward the switching command received from the actuation element 3. An additional switch control circuit 17 which is designed to process and/or forward the adjustment requests from the actuation element 3 is therefore interposed between the control circuits 2 of the electric motors 6 and the actuation elements 3. The two actuation elements 3 can obviously also be combined in all embodiments into a single actuation element. For example, a switch or controller with a plurality of switching positions can be used.

(29) The advantage of the invention now also lies in that the two electric motors can be manufactured identically, as a result of which production costs are reduced. The configuration as the master or receiver is then not implemented until later, for example during installation. However, a pre-configuration can also be performed immediately following production. Furthermore, there is no need for a separate control circuit which similarly incurs additional costs and cabling outlay. On the whole, the positioning arrangement according to the invention is therefore usable in a highly flexible manner and at low cost for a variety of applications.

REFERENCE NUMBER LIST

(30) 1 Positioning arrangement 2 Control circuit 3 Actuation element 4 First actuation element 5 Second actuation element 6 Electric motor 7 Motor driver 8 Position sensor 9 Object that is to be positioned (convertible top) 10 Positioning direction (open) 11 Positioning axis 12 Positioning direction (close) 13 Communication interface LIN interface) 14 Communication connection (LIN connection) 15 PC 16 Voltage source 17 Switch control circuit 18 Control line 19 Control line P, M Voltage signals