In one aspect, a control circuit to control a speed of a motor includes a control logic circuit connected to a multifunction port. The control logic circuit is configured to receive a control signal provided at the multifunction port and to provide response signals based on the control signal to place the motor in at least two of a sleep mode, a brake mode and a pulse-width modulation (PWM) mode. The motor control circuit also includes an H-bridge circuit configured to control the motor based on the response signals.

Motor controller having a multifunction port

An electric bending endoscope includes a temperature sensor that detects the temperature of a motor as a state value indicating the driving state of a bending drive unit. A bending control device comprises: a temperature detection unit that receives the data of the temperature detected by the temperature sensor; a record unit in which the limits of motor temperature inputted in advance are recorded; a comparison unit that compares the data of the temperature sent from the temperature detection unit with the limits of motor temperature recorded in the record unit; and a notification unit that notifies that the driving state of a motor is approaching the limit.

Electric bending endoscope

A cooling module includes, for certain embodiments, a brushless DC fan and integral fan control circuitry which independently implements a self-contained start and run motor control loop and also includes a communications port to accept commands from a host processor and to provide status and other data in response to queries from the host processor. In one embodiment, a fan module interfaces with a two-wire serial bus, such as an I2C bus or SMbus, and accepts commands and provides status and data in a serial digital format. A variety of commands such as on/off, and various speed control settings may be received from the host system, and the actual speed of the fan may be reported back when queried by the host system. In some embodiments a temperature within or near the fan housing or of the air flow through the fan may be reported back when queried. The entire fan control circuit may preferably be incorporated within the fan housing, including a serial interface and power terminals for the fan, resulting in a compact four-wire interface for the fan module.

Cooling module and related control circuits useful therefor incorporating a communication port for receiving digital command signals to control module

An apparatus including a controller, a workpiece transport in communication with the controller having a movable portion and a transport path, and a multi-dimensional position measurement device including at least one field generating platen attached to the movable portion and at least one sensor group positioned along the transport path and in communication with the controller, the field generating platen is configured for position measurement and propelling the movable portion, each sensor in the at least one sensor group is configured to provide but one output signal along a single axis corresponding to a sensed field generated by the at least one field generating platen and the controller is configured calculate a multi-dimensional position of the movable portion based on the but one output signal of at least one of the sensors in the at least one sensor group, the multi-dimensional position including a planar position and a gap measurement.

Multiple dimension position sensor

A method of controlling a motor speed for a fan assembly includes receiving a duty cycle value at a microcontroller. The microcontroller receives a measured fan speed from a speed sensor. An expected fan speed is determined, where the expected fan speed corresponds to the duty cycle value. The measured fan speed is compared with the expected fan speed. A duty cycle of a motor driving signal is reduced if the measured fan speed is less than a predetermined fraction of the expected fan speed.

Microcontroller methods of improving reliability in DC brushless motors and cooling fans

This work is on deriving precise lumped parameter thermal networks for modeling the transient thermal characteristics of electric machines under variable load conditions. The goal is to facilitate an accurate estimation of the temperatures of critical machines' components and to allow for running the derived model in real time to adapt the motor control based on the load history and maximum permissible temperatures. Consequently, the machine's capabilities can be exhausted at best considering a highly-utilized drive. The model shall be as simple as possible without sacrificing the exactness of the predicted temperatures. Accordingly, a specific lumped parameter thermal network topology was selected and its characteristics are explained in detail. The measurement data based optimization of its critical parameters through an evolutionary optimization strategy, and the therefore utilized experimental setup will be described in detail here. Measurement cycles were recorded for modeling and verification purposes including both static and dynamic test cycles with changing load torque and speed requirements. Applying the proposed hybrid approach for determining the model's parameters through involving physics-based equations as well as numerical optimization followed a significant improvement of the preciseness of the predicted motor temperatures compared to solely determining the networks's coefficients based on expert knowledge. Thereby, the validation included both the original measurement data as well as extra measurement runs. The proposed and applied strategy provides an excellent basis for future thermal modeling of electric machines.

Measurement-Based Identification of Lumped Parameter Thermal Networks for sub-Kw Outer Rotor PM Machines

Die Drehzahl eines Elektromotors (9) wird durch einen Regler (6) geregelt, der seinen Sollwert von einer Kennlinienfunktion (23) erhalt. Die Kennlinienfunktion (23) berechnet, ausgehend von einer durch einen A/D-Wandler AD (10) digital gewandelten, ursprunglich analogen Grose A (2) einen Sollwert fur den Regler (6) mit Hilfe von in einem Speicher (4) gespeicherten Stutzwerten einer Kennlinie 'MEM + DATA', wobei die nicht durch die Stutzwerte vorgegebenen Werte durch Interpolation berechnet werden.

Frank Jeske

Papers

Measurement-Based Identification of Lumped Parameter Thermal Networks for sub-Kw Outer Rotor PM Machines

Temperaturabhängige drehzahlregelung eines elektromotors mit einem mikroprozessor