Actuator with electric motor and motor controller

• US 9,548,682 B2
• Filed: 03/02/2011
• Issued: 01/17/2017
• Est. Priority Date: 03/02/2011
• Status: Active Grant

• Current Assignee: Belimo Holding AG
• Original Assignee: Belimo Holding AG
• Inventors: Guyer, Paul F., Weber, Beat, Beker, Atilla
• Primary Examiner(s): COLON SANTANA, EDUARDO
• Assistant Examiner(s): Agared, Gabriel
• Application Number:
  US14/001,416
• Publication Number:
  US 20140009087A1
• Time in Patent Office: 2,148 Days
• Field of Search: 318/53, 318/568.1, 318/568.11
• US Class Current: 1/1
• CPC Class Codes: G05B 19/414 Structure of the control system, e.g. common controller or multiprocessor systems, interface to servo, programmable interface controller
• CPC Class Codes: G05B 2219/42186 Master slave, motion proportional to axis
• CPC Class Codes: G05B 2219/42188 Slave controlled as function of reference and actual position and derived speed of master
• CPC Class Codes: H02P 5/46 for speed regulation of two or more dynamo-electric motors in relation to one another

Abstract

An actuator (1M, 1S) with a motor (12) and a motor controller (11) is configurable to operate as a master or a slave to another actuator which is coupled mechanically for driving a common load. For the case where the actuator (1M) is set as the master, the motor controller (11) receives on an input terminal (Y3) an external position control signal (pC), generates a motor control signal (sC) for controlling the motor (12) based on the position control signal (pC), and supplies the motor control signal (sC) to an output terminal (U5) for controlling a slave. For the case where the actuator (1S) is set as the slave, the motor controller (11) controls the motor (12) by supplying to the motor (12) the motor control signal (sC) received from the master. Controlling the actuators with a master improves workload balancing and reduces damages to transmission mechanics of the actuators.

Claims

1. An actuator (1, 1M, 1S, 1S′

) comprising,

an electric motor (12), and

a motor controller (11), wherein

the actuator (1, 1M, 1S, 1S′

) is switchably configurable by being dynamically and automatically set to operate as either a master or a slave to another actuator (1, 1M, 1S, 1S′

) which is coupled mechanically to the actuator (1, 1M, 1S, 1S′

) for driving a common load (L);

the motor controller (11) is configured, for the case where the actuator (1M) is dynamically and automatically set as the master, to receive on an input terminal (Y3) an external position control signal (pC), to generate based on the position control signal (pC) a motor control signal (sC), to control the motor (12) by supplying the motor control signal (sC) to the motor (12), and to control a slave by supplying the motor control signal (sC) to an output terminal (U5); and

the motor controller (11) is further configured, for the case where the actuator (1S, 1S′

) is dynamically and automatically set as the slave, to receive on the input terminal (Y3) the motor control signal (sC) supplied by the master, and to control the motor (12) by supplying the motor control signal (sC) from the master to the motor (12),

wherein the motor controller (11) is further configured to measure, at start-up time, voltage levels at the input terminal (Y3), and to set the actuator (1S, 1S′

) as a slave depending on the voltage levels measured at the input terminal (Y3), and

wherein the motor controller (11) is further configured to reduce the impedance of the input terminal (Y3), to detect at the output terminal (U5) a voltage reduction caused by a lowered impedance of another actuator (1S, 1S′

) connected to the output terminal (U5), and to set the actuator (1M) as the master upon detecting the voltage reduction at the output terminal (U5).

2. The actuator (1, 1M, 1S, 1S′

) of claim 1, wherein the motor controller (11) is further configured to set, at start-up time, a defined first voltage level at the output terminal (U5), and to set a defined second voltage level at the output terminal (U5), upon having been set as the master, the defined second voltage level being different from the first voltage level.

3. The actuator (1, 1M, 1S, 1S′

) of claim 1, wherein the motor controller (11) is further configured, for the case where the actuator (1S, 1S′

) is set as a slave, to provide on the output terminal (U5) a position signal (pN) indicating an actuator motor position.

4. The actuator (1, 1M, 1S, 1S′

) of claim 1, wherein the actuator (1, 1M, 1S, 1S′

) further comprises one or more stored actuator parameters; and

the motor controller (11) is further configured to generate the motor control signal (sC) based on the actuator parameters and the position control signal (pC).

5. The actuator (1, 1M, 1S, 1S′

) of claim 1, wherein the actuator (1) is further configurable to operate as a stand-alone actuator (1); and

the motor controller (11) is further configured, for the case where the actuator (1) is set as a stand-alone actuator (1), to receive on the input terminal (Y3) the external position control signal (pC), to generate based on the position control signal (pC) the motor control signal (sC), to control the motor (12) by supplying the motor control signal (sC) to the motor (12), and to provide on the output terminal (U5) a position signal (pN) indicating a current actuator position.

6. The actuator (1, 1M, 1S, 1S′

) of claim 1, further comprising a terminal box (6), the terminal box (6) housing electrical terminals (7a) of the actuator (1, 1M, 1S, 1S′

) and having breakthrough areas (61) for feeding electrical wires (7) through the terminal box (6) to the electrical terminals (7a).

7. The actuator (1, 1M, 1S, 1S′

) of claim 6, wherein the actuator (1, 1M, 1S, 1S′

) further comprises manual control elements (8) enclosed by the terminal box (6) terminal.

8. The actuator (1, 1M, 1S, 1S′

) of claim 6, wherein the terminal box (6) has a removable lid (60), the removable lid (60), in a closed position, protecting the electrical terminals (7a) from splash liquid, and, in an open position, enabling access to at least one of;

electrical terminals (7a) and manual control elements (8).

9. The actuator (1, 1M, 1S, 1S′

) of claim 1, further comprising a mechanical interface (4) with two openings on opposite sides for receiving a drive shaft (3), the mechanical interface (4) having arranged at one of the openings a fastener (40) for coupling the drive shaft (3) to the electric motor (12), and having inserted into the opposite one of the openings one or more support rings (2, 2′

) configured to receive the drive shaft (3) and reduce lateral movement of the drive shaft (3) with respect to a drive axis (z) running through the two openings.

10. The actuator (1, 1M, 1S, 1S′

) of claim 9, wherein the actuator (1, 1M, 1S, 1S′

) further comprises an anti-rotation member (5) arranged on a face (100) of the actuator (1, 1M, 1S, 1S′

), and the support rings (2, 2′

) are inserted in the one of the openings that is arranged on the face (100) of the actuator (1, 1M, 1S, 1S′

) having the anti-rotation member (5) arranged thereon.

11. A computer program product comprising a non-transitory computer readable medium having stored therein computer program code which directs a processor of an actuator (1, 1M, 1S, 1S′

) to;

control the actuator (1, 1M, 1S, 1S′

) to be switchably configurable by being dynamically and automatically set between being a master or a slave to another actuator (1, 1M, 1S, 1S′

) which is coupled mechanically to the actuator (1, 1M, 1S, 1S′

) for driving a common load (L),

whereby, for the case where the actuator (1M) is dynamically and automatically set as the master, the processor receives on an input terminal (Y3) of the actuator (1M) an external position control signal (pC), generates based on the position control signal (pC) a motor control signal (sC), controls a motor (12) of the actuator (1M) by supplying the motor control signal (sC) to the motor (12), and controls the slave by supplying the motor control signal (sC) to an output terminal (U5) of the actuator (1M); and

whereby, for the case where the actuator (1, 1S, 1S′

) is dynamically and automatically set as the slave, the processor receives on the input terminal (Y3) the motor control signal (sC) supplied by the master, and controls the motor (12) by supplying the motor control signal (sC) from the master to the motor (12),

wherein the motor controller (11) is further configured to measure, at start-up time, voltage levels at the input terminal (Y3), and to set the actuator (1S, 1S′

) as a slave depending on the voltage levels measured at the input terminal (Y3), and

wherein the motor controller (11) is further configured to reduce the impedance of the input terminal (Y3), to detect at the output terminal (U5) a voltage reduction caused by a lowered impedance of another actuator (1S, 1S′

) connected to the output terminal (U5), and to set the actuator (1M) as the master upon detecting the voltage reduction at the output terminal (U5).

12. A method for operating an actuator (1, 1M, 1S, 1S′

) which comprises an electric motor (12) and a motor controller (11), the method comprising;

controlling the actuator (1, 1M, 1S, 1S′

) to be switchably configurable by being dynamically and automatically set between being a master or a slave to another actuator (1, 1M, 1S, 1S′

) which is coupled mechanically to the actuator (1, 1M, 1S, 1S′

) for driving a common load (L);

whereby, for the case where the actuator (1M) is dynamically and automatically set as the master;

receiving on an input terminal (Y3) of the actuator (1M) an external position control signal (pC),

generating based on the position control signal (pC) a motor control signal (sC),

controlling a motor (12) of the actuator (1M) by supplying the motor control signal (sC) to the motor (12), and

controlling the slave by supplying the motor control signal (sC) to an output terminal (U5) of the actuator (1M); and

whereby, for the case where the actuator (1, 1S, 1S′

) is dynamically and automatically set as the slave;

receiving on the input terminal (Y3) the motor control signal (sC) supplied by the master, and

controlling the motor (12) by supplying the motor control signal (sC) from the master to the motor (12),

wherein the motor controller (11) is further configured to measure, at start-up time, voltage levels at the input terminal (Y3), and to set the actuator (1S, 1S′

) as a slave depending on the voltage levels measured at the input terminal (Y3), and

wherein the motor controller (11) is further configured to reduce the impedance of the input terminal (Y3), to detect at the output terminal (U5) a voltage reduction caused by a lowered impedance of another actuator (1S, 1S′

) connected to the output terminal (U5), and to set the actuator (1M) as the master upon detecting the voltage reduction at the output terminal (U5).