Abstract: A stepping motor control apparatus that is able to electrically detect the load of the stepping motor and effectively prevent step-outs by means of an inexpensive configuration. The stepping motor control apparatus is equipped with a microcomputer (10) that outputs a command pulse, a chopper-type constant current driver (20) that outputs a drive current that corresponds to the input command pulse to the stepping motor (5) and outputs a chopper signal to keep the output drive current fixed, and a load detection circuit (30) that detects the chopper signal to detect the load of the stepping motor (5). The load detection circuit (30) is equipped with a waveform shaping circuit (50) that makes the chopper signal waveform continuous to convert it to a pulse or voltage, and it detects the load of the stepping motor by means of the width of the pulse or the voltage value.

Abstract: A shutter mechanism includes a drum (2), a stepping motor (5), a driver (20), a microcomputer (10), a memory (16), and a load magnitude detection circuit (30) that detects the magnitude of the load on the stepping motor (5) when an object such as a shutter (3) is either wound or unwound from the drum (2). The microcomputer (10) can set the upper and lower limit stopping positions of the shutter (3) by resetting the number of command pulses stored in the memory (16) when the load magnitude detection circuit (30) detects an increase in the load at the stepping motor (5), and storing the number of command pulses output to that point from the memory (16) when the load magnitude detection circuit (30) next detects an increase in the load at the stepping motor (5) after the outputting of the command pulses is next restarted.

Abstract: A stepping motor comprises a permanent magnet type rotor with a plurality of poles secured to a rotating shaft and a stator having stator magnetic poles with stator magnetic pole teeth in which excitation windings are wound on a plurality of magnetic poles in a star or delta connection, wherein the rotor is magnetized in different directions alternately circumferentially to satisfy the following equation: M=4F/3 where M is the number of poles of the rotor and F is the number of the stator magnetic poles, the rotor is cylindrical in shape with the stator rotatably disposed inside, disposed opposing the surfaces of the stator magnetic pole teeth through an air gap which is of a uniform dimension throughout the circumference between the surfaces of the stator magnetic pole teeth of the stator and the rotor, and the surface magnetic flux distribution thereof has a substantially sinusoidal wave form circumferentially. The stepping motor realizes smooth rotation and simplification in the structure of the rotor.

Abstract: A stepping motor control apparatus that is able to electrically detect the load of the stepping motor and effectively prevent step-outs by means of an inexpensive configuration. The stepping motor control apparatus is equipped with a microcomputer (10) that outputs a command pulse, a chopper-type constant current driver (20) that outputs a drive current that corresponds to the input command pulse to the stepping motor (5) and outputs a chopper signal to keep the output drive current fixed, and a load detection circuit (30) that detects the chopper signal to detect the load of the stepping motor (5). The load detection circuit (30) is equipped with a waveform shaping circuit (50) that makes the chopper signal waveform continuous to convert it to a pulse or voltage, and it detects the load of the stepping motor by means of the width of the pulse or the voltage value.

Abstract: A shutter mechanism includes a drum (2), a stepping motor (5), a driver (20), a microcomputer (10), a memory (16), and a load magnitude detection circuit (30) that detects the magnitude of the load on the stepping motor (5) when an object such as a shutter (3) is either wound or unwound from the drum (2). The microcomputer (10) can set the upper and lower limit stopping positions of the shutter (3) by resetting the number of command pulses stored in the memory (16) when the load magnitude detection circuit (30) detects an increase in the load at the stepping motor (5), and storing the number of command pulses output to that point from the memory (16) when the load magnitude detection circuit (30) next detects an increase in the load at the stepping motor (5) after the outputting of the command pulses is next restarted.

Abstract: A stepping motor comprises a permanent magnet type rotor with a plurality of poles secured to a rotating shaft and a stator having stator magnetic poles with stator magnetic pole teeth in which excitation windings are wound on a plurality of magnetic poles in a star or delta connection, wherein the rotor is magnetized in different directions alternately circumferentially to satisfy the following equation: M=4F/3 where M is the number of poles of the rotor and F is the number of the stator magnetic poles, the rotor is cylindrical in shape with the stator rotatably disposed inside, disposed opposing the surfaces of the stator magnetic pole teeth through an air gap which is of a uniform dimension throughout the circumference between the surfaces of the stator magnetic pole teeth of the stator and the rotor, and the surface magnetic flux distribution thereof has a substantially sinusoidal wave form circumferentially.

Abstract: A stepping motor comprises a permanent magnet type rotor with a plurality of poles secured to a rotating shaft and a stator having stator magnetic poles with stator magnetic pole teeth in which excitation windings are wound on a plurality of magnetic poles in a star or delta connection, wherein the rotor is magnetized in different directions alternately circumferentially to satisfy the following equation: M=4F/3 where M is the number of poles of the rotor and F is the number of the stator magnetic poles, the rotor is cylindrical in shape with the stator rotatably disposed inside, disposed opposing the surfaces of the stator magnetic pole teeth through an air gap which is of a uniform dimension throughout the circumference between the surfaces of the stator magnetic pole teeth of the stator and the rotor, and the surface magnetic flux distribution thereof has a substantially sinusoidal wave form circumferentially.

Abstract: A stepping motor comprises a permanent magnet type rotor with a plurality of poles secured to a rotating shaft and a stator having stator magnetic poles with stator magnetic pole teeth in which excitation windings are wound on a plurality of magnetic poles in a star or delta connection, wherein the rotor is magnetized in different directions alternately circumferentially to satisfy the following equation: M=4F/3 where M is the number of poles of the rotor and F is the number of the stator magnetic poles, the rotor is cylindrical in shape with the stator rotatably disposed inside, disposed opposing the surfaces of the stator magnetic pole teeth through an air gap which is of a uniform dimension throughout the circumference between the surfaces of the stator magnetic pole teeth of the stator and the rotor, and the surface magnetic flux distribution thereof has a substantially sinusoidal wave form circumferentially.