1. An output control device of a generation device for controlling an output of the generation device that supplies power to a DC load including voltage accumulation means using an AC generator including a rotor having a magnetic field and a stator having an armature winding comprised of polyphase coils as a power supply, comprising:
a rectifier circuit that has a plurality of input terminals to which an output of said armature winding is input and a pair of output terminals connected across said voltage accumulation means, converts an AC voltage input to said input terminals into a DC voltage, and outputs the DC voltage from said output terminals;
an inverter circuit having DC terminals and AC terminals connected to the output terminals and the input terminals of said rectifier circuit; and
a control portion having inverter control means that controls said inverter circuit to convert a voltage across the voltage accumulation means connected across the output terminals of said rectifier circuit into an AC control voltage having the same number of phases and the same frequency as the output of said generator, and supply said AC control voltage from said AC terminals to said armature winding,
wherein said control portion includes maximum output current phase detection means for detecting a phase of a phase current of said armature winding as a maximum output current phase, and
said inverter control means includes means for arithmetically operating a target phase of said AC control voltage required for changing an output voltage of said generator in a direction of the output voltage of said rectifier circuit approaching a target voltage, and is comprised so as to control said inverter circuit so that a phase of the AC control voltage applied to said armature winding is equal to the arithmetically operated target phase when the arithmetically operated target phase is advanced with respect to said maximum output current phase, while the phase of the AC control voltage applied to said armature winding is equal to said maximum output current phase when the arithmetically operated target phase is equal to or delayed with respect to said maximum output current phase, thereby controlling the output voltage of said rectifier circuit to approach said target voltage.
2. An output control device of a generation device for controlling an output of the generation device that supplies power to a DC load including voltage accumulation means using an AC generator including a rotor having a magnetic field and a stator having an armature winding comprised of polyphase coils as a power supply, comprising:
a rectifier circuit that has a plurality of input terminals to which an output of said armature winding is input and a pair of output terminals connected across said voltage accumulation means, converts an AC voltage input to said input terminals into a DC voltage, and outputs the DC voltage from said output terminals;
an inverter circuit having DC terminals and AC terminals connected to the output terminals and the input terminals of said rectifier circuit; and
a control portion having inverter control means that controls said inverter circuit to convert a voltage across the voltage accumulation means connected across the output terminals of said rectifier circuit into an AC control voltage having the same number of phases and the same frequency as the output of said generator, and supply said AC control voltage from said AC terminals to said armature winding,
wherein said control portion includes maximum output current phase detection means for detecting a phase of a phase current of said armature winding as a maximum output current phase,
a range of change in a rotational speed of said generator is divided into an output current increasing area in which an output current of said generation device can be increased more than an output current of said generation device when no AC control voltage is applied to said armature winding by delaying a phase of said AC control voltage, and an output current nonincreasing area in which the output current of said generation device cannot be increased more than the output current of said generation device when no AC control voltage is applied to said armature winding even by delaying the phase of said AC control voltage,
said inverter control means includes means for arithmetically operating a target phase of said AC control voltage required for changing an output voltage of said generator in a direction of the output voltage of said rectifier circuit approaching a target voltage, and is comprised so as to control said inverter circuit so that a phase of the AC control voltage applied to said armature winding is equal to the arithmetically operated target phase when the rotational speed of said generator is in said output current increasing area and the arithmetically operated target phase is advanced with respect to a determination phase preset within a range in which the phase is not delayed with respect to said maximum output current phase, the phase of the AC control voltage applied to said armature winding is equal to the arithmetically operated target phase when the rotational speed of said generator is in said output current increasing area and the arithmetically operated target phase is delayed with respect to said determination phase and advanced with respect to said maximum output current phase, the phase of the AC control voltage applied to said armature winding is equal to said maximum output current phase when the rotational speed of said generator is in said output current increasing area and the arithmetically operated target phase is delayed with respect to said determination phase and equal to or delayed with respect to said maximum output current phase, the phase of the AC control voltage applied to said armature winding is equal to the arithmetically operated target phase when the rotational speed of the generator is in the output current nonincreasing area and the arithmetically operated target phase is advanced with respect to said maximum output current phase, and the phase of the AC control voltage applied to said armature winding is equal to said maximum output current phase when the rotational speed of said generator is in said output current nonincreasing area and the arithmetically operated target phase is equal to or delayed with respect to said maximum output current phase, thereby controlling the output voltage of said rectifier circuit to approach said target voltage, and
said determination phase is determined so that the output of said generator is always increased when the rotational speed of said generator is in said output current increasing area and the phase of the AC control voltage applied to said armature winding is delayed within a range not exceeding said determination phase.
3. The output control device of a generation device according to claim 1, further comprising: a signal generator that generates a signal including information on a rotational angle position of said rotor when the rotational angle position of the rotor of said generator matches a predetermined position; a current sensor that detects a phase current of said generator; and a zero cross detection circuit that detects a zero cross point of said phase current from the output of said current sensor,
wherein said maximum output current phase detection means is comprised so as to detect a phase of said phase current from a timing of said signal generator generating the signal and the zero cross point of the phase current detected by said zero cross detection circuit.
4. The output control device of a generation device according to claim 2, further comprising: a signal generator that generates a signal including information on a rotational angle position of said rotor when the rotational angle position of the rotor of said generator matches a predetermined position; a current sensor that detects a phase current of said generator; and a zero cross detection circuit that detects a zero cross point of said phase current from the output of said current sensor,
wherein said maximum output current phase detection means is comprised so as to detect a phase of said phase current from a timing of said signal generator generating the signal and the zero cross point of the phase current detected by said zero cross detection circuit.
5. The output control device of a generation device according to claim 1, wherein said inverter circuit is comprised of a bridge type circuit with arms of a bridge being comprised of MOSFETs,
said control device further comprises: a pulse signal generator that generates a pulse when a rotational angle position of the rotor of said generator matches a predetermined position; a voltage sensor that detects a voltage between the drain and source of a MOSFET that constitutes one arm of the bridge of said inverter circuit; and a zero cross detection circuit that detects a timing of an output of said voltage sensor changing from a high level to a zero level as a zero cross point of said phase current, and
said maximum output current phase detection means is comprised so as to detect a phase of said phase current from the timing of said signal generator generating the signal and the zero cross point of the phase current detected by said zero cross detection circuit, and
said inverter control means is comprised so as to determine that maximum output current phase control is performed for making the phase of the AC control voltage applied to said armature winding equal to the detected maximum output current phase when a difference between the phase of the present AC control voltage and the maximum output current phase detected by said maximum output current phase detection means is within a predetermined range, and advance said AC control voltage by a predetermined phase when a state where it is determined that the maximum output current phase control is performed lasts for a predetermined time.
6. The output control device of a generation device according to claim 2, wherein said inverter circuit is comprised of a bridge type circuit with arms of a bridge being comprised of MOSFETs,
said control device further comprises: a pulse signal generator that generates a pulse when a rotational angle position of the rotor of said generator matches a predetermined position; a voltage sensor that detects a voltage between the drain and source of a MOSFET that constitutes one arm of the bridge of said inverter circuit; and a zero cross detection circuit that detects a timing of an output of said voltage sensor changing from a high level to a zero level as a zero cross point of said phase current,
said maximum output current phase detection means is comprised so as to detect a phase of said phase current from the timing of said signal generator generating the signal and the zero cross point of the phase current detected by said zero cross detection circuit, and
said inverter control means is comprised so as to determine that maximum output current phase control is performed for making the phase of the AC control voltage applied to said armature winding equal to the detected maximum output current phase when a difference between the phase of the present AC control voltage and the maximum output current phase detected by said maximum output current phase detection means is within a predetermined range, and advance said AC control voltage by a predetermined phase when a state where it is determined that the maximum output current phase control is performed lasts for a predetermined time.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
What is claimed is:
1. A motor assembly with improved sealing properties, comprising:
a motor having a rotatable shaft;
a working air fan assembly carried by said shaft, said working air fan assembly moving air therethrough; and
a sealed bearing interposed between said working air fan assembly, said sealed bearing having an inner ring rotatable with respect to an outer ring, and a seal carried by one of said rings, said seal frictionally contacting the other of said rings.
2. The motor assembly according to claim 1, wherein said sealed bearing further comprises:
a frame carried by one of said rings, said frame holding said seal, said frame compressing a portion of said seal so as to urge a remaining portion of said seal into contact with the other said ring.
3. The motor assembly according to claim 2, wherein said outer ring has a notch that securably receives said frame.
4. The motor assembly according to claim 1, wherein said seal is made of expanded polytetrafluoroethylene.
5. The motor assembly according to claim 1, wherein said seal withstands temperatures of about between 450 F. to about 600 F.
6. The motor assembly according to claim 1, wherein said seal is chemically resistant to media in the 0-14 pH range except molten alkali materials.
7. A sealed bearing, comprising:
an outer ring, said outer ring having an inner diameter;
an inner ring, said inner ring having an outer diameter;
a plurality of rolling elements disposed between said outer ring and said inner ring; and
a seal carried by one of said rings, said seal frictionally contacting the other of said rings.
8. The bearing according to claim 10, wherein said inner diameter has at least one annular notch from which outwardly extends an annular lip, said annular notch and said annular lip securably receiving and supporting said seal.
9. The bearing according to claim 11, further comprising:
a seal frame that carries said seal, said seal frame securably received in said annular notch.
10. The bearing according to claim 12, wherein said seal frame compresses at least a portion of said seal and urges an uncompressed portion of said seal into contact with the other of said rings.
11. The bearing according to claim 10, wherein said seal is made of expanded polytetrafluoroethylene.
12. The seal according to claim 7, wherein said seal withstands temperatures of about between 450 F. to about 600 F.
13. The seal according to claim 7, wherein said seal is chemically resistant to media in the 0-14 pH range except molten alkali metals.