Abstract: An overload current control circuit for a DC motor comprises: a DC motor, a DC power source, a power semiconductor assembly, and a sampling resistor that are connected in series. The overload current control circuit further comprises a voltage polarity switching circuit that is connected to a circuit between the sampling resistor and the overload protection and detection circuit to control the single polarity of the sampling voltage of the first and second terminals of the sampling resistor, so as to provide constant voltage potential to the overload protection and detection circuit, thus providing overload protection to the DC motor.

Abstract: A positioning structure of a magnetic induction ruler comprises a base, an induction ruler and a fixing assembly. In one end of the base is formed a first positioning portion, one end of the fixing assembly is formed with a second positioning portion, and the other end of the fixing assembly is formed with a restriction portion. The positioning member of the second positioning portion of the fixing assembly is inserted in the positioning hole of the first positioning portion, enabling both ends of the induction ruler to be fixed to the base by the pressure of the restriction portion of the fixing assembly. Thereby, the magnetic member and the metal members of the induction ruler can be stuck to each other firmly.

Abstract: A clearance eliminating structure for a shaft of a direct drive torque motor comprises: a body, a direct drive torque motor, a bearing assembly and an adjustment nut. The main shaft includes a plurality of stages which are used to positioning the torque motor and the bearing assembly, and then torque motor and the bearing assembly are used to position the body. The main shaft is formed at the end with threads for enabling the adjustment nut to press tightly against the respective components on the main shaft. When the present invention is used on the assembly of the direct drive torque motor, which can not only simplify the assembly operation, improve the reliability, but also eliminate the clearance of the main shaft to increase the service life of the product.

Abstract: A method of arranging a resolver comprises the steps of: a, setting stator magnetic poles number of the resolver Ns as a number being in integral multiples (t) of a phase number q; b, figuring out rotor magnetic pole number Nr based on a formula; c, arranging the stator and the rotor based on the stator magnetic poles number of the resolver Ns and the rotor magnetic pole number Nr, and producing signals with phase differences.

Abstract: An extendible and retractable actuator comprises a motor, two screws and an extendible and retractable sleeve assembly. The motor cooperates with the screws to drive the extendible and retractable sleeve assembly to extend and retract simultaneously, so as to reduce the extending and retracting time and to simplify the structure of the extendible and retractable actuator.

Abstract: A locking structure for an upper cover and an outer housing of a motor, the motor comprises an outer housing, an upper cover and at least two locking members. The upper cover is mounted on one end of the outer housing, and the locking members are locked in the outer housing by screws that pass through the upper cover, such that the upper cover and the outer housing are locked with each other stably and easily.

Abstract: A power-generating magnetic sensing equipment comprises a magnetic sensing read head and a magnetic scale. The magnetic sensing read head includes a power-generating device and a signal sensing control device. The magnetic sensing read head moves with respect to the magnetic scale to make the power-generating device produce changes of magnetic field to induce the electric current, so that the power-generating device is able to continuously supply the power to the signal sensing control device, thus keeping the signal transmission uninterrupted.