Disk drive apparatus and motor

A disk drive apparatus comprising:

• head means for reproducing a signal from a disk;
• processing means for processing an output signal from said head means and outputting a processed signal;
• a rotor, having a field part which generates field fluxes, for driving said disk;
• Q-phase windings (Q is an integer of 3 or more);
• voltage supplying means, including two output terminals, for supplying a DC voltage;
• power supplying means having Q first power transistors and Q second power transistors, each of said Q first power transistors forming a current path between one output terminal side of said voltage supplying means and one of said Q-phase windings, and each of said Q second power transistors forming a current path between the other output terminal side of said voltage supplying means and one of said Q-phase windings;
• position detecting means for producing a position signal which responds with the rotation of said rotor;
• activation operation means for controlling active periods of said Q first power transistors and said Q second power transistors responding with an output signal of said position detecting means, each of said active periods being larger than the period of 360/Q electrical degrees;
• commanding means for producing a command signal which responds with a rotational speed of said disk;
• and
• switching operation means for causing at least one of said Q first power transistors and said Q second power transistors to perform high-frequency switching responding with said command signal;
• and that
• each of said Q first power transistors is a first NMOS-FET power transistor for forming a current path from the positive terminal side of said voltage supplying means to one of said Q-phase windings,
• each of said Q second power transistors is a second NMOS-FET power transistor for forming a current path from the negative terminal side of said voltage supplying means to one of said Q-phase windings,
• said switching operation means includes:
• current detecting means for producing a current detection signal which responds with or corresponds to a composed current to said Q-phase windings from said voltage supplying means, and
• switching control means for producing a switching pulse signal which responds with said current detection signal and said command signal, and
• said activation operation means produces at least a slew-rate switching signal at a control terminal side of at least one power transistor among said first NMOS-FET power transistors responding with said switching pulse signal, said at least a slew-rate switching signal having a smoothed voltage slope in at least one of rising and falling slopes, and causes said at least one power transistor to follow said at least a slew-rate switching signal, thereby supplying a high-frequency switching drive voltage signal to one terminal of said Q-phase windings, said high-frequency switching drive voltage signal having smoothed voltage slopes and responding with said current detection signal and said command signal.

A disk drive apparatus comprising:

• head means for reproducing a signal from a disk;
• processing means for processing an output signal from said head means and outputting a processed signal;
• a rotor, having a field part which generates field fluxes, for driving said disk;
• Q-phase windings (Q is an integer of 3 or more);
• voltage supplying means, including two output terminals, for supplying a DC voltage;
• power supplying means having Q first power transistors and Q second power transistors, each of said Q first power transistors forming a current path between one output terminal side of said voltage supplying means and one of said Q-phase windings, and each of said Q second power transistors forming a current path between the other output terminal side of said voltage supplying means and one of said Q-phase windings;
• position detecting means for producing a position signal which responds with the rotation of said rotor;
• activation operation means for controlling active periods of said Q first power transistors and said Q second power transistors responding with an output signal of said position detecting means, each of said active periods being larger than the period of 360/Q electrical degrees;
• commanding means for producing a command signal which responds with a rotational speed of said disk;
• and
• switching operation means for causing at least one of said Q first power transistors and said Q second power transistors to perform high-frequency switching responding with said command signal;
• and that
• said switching operation means includes:
• current detecting means for producing a current detection signal which responds with or corresponds to a composed current to said Q-phase windings from said voltage supplying means, and
• switching control means for producing a switching pulse signal which responds with said current detection signal and said command signal, and
• said activation operation means produces two slew-rate switching signals which responds with said switching pulse signal at control terminal sides of two of said Q first power transistors, each of said two slew-rate switching signals having a smoothed voltage slope in at least one of rising and falling slopes, and causes said two of said Q first power transistors to perform high-frequency switching substantially simultaneously responding with said two slew-rate switching signals, when said two of said Q first power transistors alter current paths to said Q-phase windings while at least one of said Q second power transistors remains ON without ON-OFF switching.

A motor comprising:

• a rotor having a field part which generates field fluxes;
• Q-phase windings (Q is an integer of 3 or more);
• voltage supplying means, including two output terminals, for supplying a DC voltage;
• power supplying means having Q first power transistors and Q second power transistors, each of said Q first power transistors forming a current path between one output terminal side of said voltage supplying means and one of said Q-phase windings, and each of said Q second power transistors forming a current path between the other output terminal side of said voltage supplying means and one of said Q-phase windings;
• position detecting means for producing a position signal which responds with the rotation of said rotor;
• activation operation means for controlling active periods of said Q first power transistors and said Q second power transistors responding with an output signal of said position detecting means, each of said active periods being larger than the period of 360/Q electrical degrees;
• commanding means for producing a command signal which responds with a rotational speed of said rotor;
• and
• switching operation means for causing at least one of said Q first power transistors and said Q second power transistors to perform high-frequency switching responding with said command signal;
• and that
• said switching operation means includes:
• current detecting means for producing a current detection signal which responds with or corresponds to a composed current to said Q-phase windings from said voltage supplying means, and
• switching control means for producing a switching pulse signal which responds with said current detection signal and said command signal, and
• said activation operation means produces at least a slew-rate switching signal which responds with said switching pulse signal at a control terminal side of at least one power transistor among said Q first power transistors and said Q second power transistors, said at least a slew-rate switching signal having a smoothed voltage slope in at least one of rising and falling slopes, and causes said at least one power transistor to follow said at least a slew-rate switching signal, thereby supplying a high-frequency switching drive voltage signal to one terminal of said Q-phase windings, said high-frequency switching drive voltage signal having smoothed voltage slopes and responding with said current detection signal and said command signal.

A motor comprising:

• a rotor having a field part which generates field fluxes;
• Q-phase windings (Q is an integer of 3 or more);
• voltage supplying means, including two output terminals, for supplying a DC voltage;
• power supplying means having Q first power transistors and Q second power transistors, each of said Q first power transistors forming a current path between one output terminal side of said voltage supplying means and one of said Q-phase windings, and each of said Q second power transistors forming a current path between the other output terminal side of said voltage supplying means and one of said Q-phase windings;
• position detecting means for producing a position signal which responds with the rotation of said rotor;
• activation operation means for controlling active periods of said Q first power transistors and said Q second power transistors responding with an output signal of said position detecting means, each of said active periods being larger than the period of 360/Q electrical degrees;
• commanding means for producing a command signal which responds with a rotational speed of said rotor;
• and
• switching operation means for causing at least one of said Q first power transistors and said Q second power transistors to perform high-frequency switching responding with said command signal;
• and that
• each of said Q first power transistors is a first NMOS-FET power transistor for forming a current path from the positive terminal side of said voltage supplying means to one of said Q-phase windings,
• each of said Q second power transistors is a second NMOS-FET power transistor for forming a current path from the negative terminal side of said voltage supplying means to one of said Q-phase windings,
• said switching operation means includes:
• current detecting means for producing a current detection signal which responds with or corresponds to a composed current to said Q-phase windings from said voltage supplying means, and
• switching control means for producing a switching pulse signal which responds with said current detection signal and said command signal, and
• said activation operation means produces at least a slew-rate switching signal at a control terminal side of at least one power transistor among said first NMOS-FET power transistors responding with said switching pulse signal, said at least a slew-rate switching signal having a smoothed voltage slope in at least one of rising and falling slopes, and causes said at least one power transistor to follow said at least a slew-rate switching signal, thereby supplying a high-frequency switching drive voltage signal to one terminal of said Q-phase windings, said high-frequency switching drive voltage signal having smoothed voltage slopes and responding with said current detection signal and said command signal.

A motor comprising:

• a rotor having a field part which generates field fluxes;
• Q-phase windings (Q is an integer of 3 or more);
• voltage supplying means, including two output terminals, for supplying a DC voltage;
• power supplying means having Q first power transistors and Q second power transistors, each of said Q first power transistors forming a current path between one output terminal side of said voltage supplying means and one of said Q-phase windings, and each of said Q second power transistors forming a current path between the other output terminal side of said voltage supplying means and one of said Q-phase windings;
• position detecting means for producing a position signal which responds with the rotation of said rotor,
• activation operation means for controlling active periods of said Q first power transistors and said Q second power transistors responding with an output signal of said position detecting means, each of said active periods being larger than the period of 360/Q electrical degrees;
• commanding means for producing a command signal which responds with a rotational speed of said rotor;
• and
• switching operation means for causing at least one of said Q first power transistors and said Q second power transistors to perform high-frequency switching responding with said command signal;
• and that
• said switching operation means includes:
• current detecting means for producing a current detection signal which responds with or corresponds to a composed current to said Q-phase windings from said voltage supplying means, and
• switching control means for producing a switching pulse signal which responds with said current detection signal and said command signal, and
• said activation operation means produces two slew-rate switching signals which responds with said switching pulse signal at control terminal sides of two of said Q first power transistors, each of said two slew-rate switching signals having a smoothed voltage slope in at least one of rising and falling slopes, and causes said two of said Q first power transistors to perform high-frequency switching substantially simultaneously responding with said two slew-rate switching signals, when said two of said Q first power transistors alter current paths to said Q-phase windings while at least one of said Q second power transistors remains ON without ON-OFF switching.