1. A fuel injection device comprising:
an injector that injects fuel into a cylinder of an engine;
a fuel injection amount obtaining unit that obtains a fuel injection amount of fuel injected by the injector;
a heat generation amount obtaining unit that obtains a heat generation amount of the fuel injected by the injector and ignited; and
a control unit that determines that injector abnormality occurs, when determining that a difference between a fuel injection amount obtained by the fuel injection amount obtaining unit and a reference fuel injection amount is within a predetermined range and that a heat generation amount obtained by the heat generation amount obtaining unit is greater than a reference heat generation amount corresponding to the reference fuel injection amount.
2. The fuel injection device of claim 1, wherein the control unit determines whether or not the injector abnormality occurs by comparing a fuel injection amount of pilot injection with the reference fuel injection amount and by comparing a heat generation amount of the pilot injection with the reference heat generation amount.
3. The fuel injection device of claim 1, wherein the control unit determines whether or not the injector abnormality occurs by comparing a heating amount, of single-shot injection of the single-shot fuel injection performed in performing fuel cut control, with the reference heat generation amount.
4. The fuel injection device of claim 1, wherein the heat generation amount obtaining unit obtains a heat generation amount of the ignited fuel based on an in-cylinder pressure.
5. The fuel injection device of claim 1, wherein the heat generation amount obtaining unit obtains a heat generation amount of the ignited fuel based on a pressure change in fuel introduced to the injector.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A brushless rotary motor comprising:
a rotor having a rotor axis and a magnet assembly that includes a plurality of permanent magnets that are held together such that same magnetic poles contact one another; and
a stator including magnetic coils encircling the rotor, the rotor and the stator being changeable in position relative to one another;
wherein each of the plurality of permanent magnets is a crescent-shaped magnet that is magnetized in a circular direction on a plane vertical to the rotor axis,
the magnet assembly is held at its upper and lower parts and outside perimeter by magnetic yokes such that the plurality of crescent-shaped magnets make a ring shape while the same magnetic poles contact one another,
the magnet assembly generates a strongest magnetic field along a magnetic field direction lying in multiple radial directions along each homopolar contact plane at which the same magnetic poles contact one another,
the magnetic coils are positioned so that current flows in a direction intersecting the magnetic field direction, and
the magnetic coils include a plurality of A phase coils and a plurality of B phase coils, a selected one of the A and B phase coils is located inside the ring shaped magnetic assembly, and the other of the A and B phase coils is located outside the ring shaped magnetic assembly.
2. A robot comprising the brushless rotary motor according to claim 1.
3. A moving body comprising the brushless rotary motor according to claim 1.