JPH0192528A - Turbocharger provided with electric rotary machine - Google Patents

Abstract

PURPOSE:To make it possible to precisely detect the position of a magnetic pole of a rotor by providing a permanent magnet to be detected, on a rotary shaft, and by providing a means for detecting a rotating position of the permanent magnet to be detected and a means for shielding the detecting means in a stationary part. CONSTITUTION:When a turbo-charger is driven so that a compressor impeller 1 and a rotor 3 are rotated through a rotary shaft 4, a detection permanent magnet 52 attached to the forward end of the rotary shaft 4 by means of a nut 41 is also rotated so that a magnetic sensor 62 detects a variation in magnetic field and delivers a signal to a control circuit. The signal delivered at that time corresponds to the rotating position of the magnetic pole of the rotor 3, and accordingly it is possible to precisely detect a variation in a magnetic field and the phase thereof during rotation of the rotor 3. Further, since variations in magnetic field due to the permanent magnet of the rotor 3 and the coils in the stator 7 are restrained by a shield plate 8, it is possible to obtain a detection signal having a satisfactory S/N ratio.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a turbocharger with a rotating electric machine driven by exhaust energy of an internal combustion engine.

(Prior Art) In recent years, turbochargers equipped with an exhaust turbine driven by the energy of the exhaust gas of an internal combustion engine and a compressor that supercharges intake air into the cylinder by the drive of the turbine have been frequently used. A turbo is provided with a rotating electric machine and operates the rotating electric machine as an electric motor to supercharge and assist the intake air of the internal combustion engine when the engine is running at low speed and under heavy load, and to charge a battery with electric power generated by generator operation during light load. charger is being developed.

As a turbocharger equipped with this kind of rotating electric machine,
JP-A-60-195329 discloses a turbocharger for an internal combustion engine that operates as a motor or a generator depending on the operating state of the engine.

Further, Japanese Patent Application No. 61-95970 discloses a turbocharger generator in which a rotor structure and a heat insulating part structure of a rotating electric machine are proposed.

(Problems to be Solved by the Invention) The above-mentioned proposals for turbochargers for internal combustion engines and generators for turbochargers lack means for detecting the position of the magnetic poles of a rotor equipped with permanent magnets. For,
When a rotating electrical machine is driven to rotate at high speed, it is impossible to control the phase of the power supplied to the corresponding stator, which makes it difficult to drive it with high efficiency.

For this reason, detection devices with magnetic sensors or optical sensors attached to a rotating body are used, but in the case of a turbocharger with a rotating electric machine, a strong permanent magnet is attached to the shaft as a rotor. When operating an electric motor, a large current is passed through the stator coil, so the magnetic sensor is affected by a strong magnetic field, making it impossible to accurately detect the rotor position. .

The present invention has been made in view of the above points, and its purpose is to provide a magnetic sensor with a structure that is not affected by the magnetic field caused by permanent magnets and coils, thereby enabling highly accurate position detection using a magnetic sensor. The present invention provides a turbocharger with a rotating electric machine.

(Means for Solving the Problems) According to the present invention, in a turbocharger with a rotating electrical machine in which a rotor having a permanent magnet is provided on the rotating shaft of the turbocharger driven by exhaust energy of an internal combustion engine, the permanent magnet A permanent magnet for detection corresponding to the magnetic pole position is provided on the rotating shaft, and a detection means for detecting the position of the magnet for detection during rotation is provided on the fixed part, and the detection operation of the detection means is controlled by the external magnetic field. It is possible to provide a turbocharger with a rotating electrical machine that is equipped with a shielding means for shielding from the influence.

(Function) In the present invention, a permanent magnet is attached to the rotating part of the turbocharger as a detection means corresponding to the magnetic pole position of the permanent magnet of the rotor, and a shielding means is used to separate the detection means and the corresponding detection means. Since shielding is performed to increase the S/N ratio of the detection signal, a signal of sufficient strength can be obtained, and the position of the rotating magnetic pole can be accurately detected.

(Example) Next, an example of the present invention will be described in detail using the drawings.

FIG. 1 is an explanatory diagram showing a first embodiment of the present invention, showing a cross section of a portion between a compressor impeller and a rotating electric machine of a turbocharger, and a turbine impeller is attached to the right side thereof.

In the figure, reference numeral 1 denotes a compressor impeller that supercharges the intake air of an engine (not shown), and the rotation of the turbine impeller, which is rotationally driven by exhaust energy,
It is transmitted to the compressor impeller 1 via.

3 is a rotor, 7 is a stator, which constitutes a rotating electrical machine.
The rotor 3 is made of a permanent magnet that has strong magnetic force.
The stator 7 has a coil and supplies current to the coil when the motor is operating, and extracts the electromotive force of the coil to the outside when the generator is operating. 2 is a spacer, and rotor 4
and the compressor impeller 1 to maintain a predetermined distance between these two members, and a nut 4.
1, the corresponding mutual positions of the rotor 4 and the compressor impeller 1 are fixed.

5 is a permanent magnet for detection embedded in the back of the blade of the compressor impeller 1. For example, if the permanent magnet of the rotor 4 has two poles, an N pole and an S pole, the magnetic pole positions of the N and S poles are determined. 1(b), respectively.

6 is a magnetic sensor, the base of which is attached to the housing of the turbocharger, the sensor having a detection coil at the tip emits a signal in response to a change in the magnetic field, and a permanent magnet for detection by the rotation of the compressor impeller 1; Changes in the magnetic field generated by driving the stator 5 are detected and the output signal is input to a control device connected to the coil of the stator 7.

Reference numeral 8 denotes a shielding plate made of a thin ferromagnetic plate, which is attached to the housing of a turbocharger (not shown) and protects against changes in the magnetic field due to the rotation of the permanent magnets of the rotor 3 and changes in the magnetic field due to current changes in the coil of the stator 7. The shielding plate 8 absorbs the influence of the changes, and is configured to suppress noise generated in the magnetic sensor 6 due to these magnetic changes.

In this embodiment configured in this way, when the turbocharger is driven by exhaust energy and the compressor impeller 1 and rotor 3 are rotated, the detection permanent magnet 5 embedded in the compressor impeller 1 also rotates. Therefore, the magnetic sensor 6 detects a change in the magnetic field and sends a signal to the control device. Since this transmitted signal corresponds to the rotational position of the magnetic poles of the rotor 3, changes in the magnetic field during rotation of the rotor 3 and its phase can be accurately detected. 3 permanent magnet and stator 7
Since changes in the magnetic field due to the coil are suppressed, S/
A detection signal with a good N ratio can be obtained. Note that even when the compressor impeller 1 rotates at an extremely high speed, since the detection permanent magnet 5 is buried, the influence of centrifugal force is small, and the rotational balance can be easily adjusted.

FIG. 2 is an explanatory diagram showing a second embodiment of the present invention, in which a thin layer 51 of amorphous silicon steel material is provided in place of the detection permanent magnet 5 in the first embodiment. Components that are the same as those shown in are given the same reference numerals.

Reference numeral 11 shown in FIG. 2 is a compressor impeller, which is made of a non-magnetic material such as an aluminum alloy. As shown in (b), a thin film 51 made of amorphous silicon steel is firmly deposited. Reference numeral 61 denotes a magnetic sensor, which itself has a magnetic pole and a detection coil, and detects changes in the magnetic field that change when a magnetic body approaches the magnetic sensor 61, and the detection coil sends a signal to a control device (not shown). is configured to be sent to

In the second embodiment configured in this manner, when the compressor impeller 11 and the rotor 3 are driven to rotate, the thin layer 51 of amorphous silicon steel material attached to the compressor impeller 11 is also rotated. A non-magnetic aluminum alloy passing near the magnetic sensor 61,
The magnetic field changes due to the influence of the ferromagnetic thin film 51, and the magnetic sensor 61 emits a detection signal each time the thin film 51 passes. Since this transmission corresponds to the rotational position of the magnetic pole of the rotor 3, the position of the magnetic pole of the rotor 3 during rotation can be accurately grasped.

FIG. 3 is an explanatory diagram showing a third embodiment of the present invention, and shows an example in which a permanent magnet for detection is provided between a compressor impeller and a tightening nut, and is the same as FIG. 1 above. The parts are given the same reference numerals.

In FIG. 3, reference numeral 52 denotes a cylindrical detection permanent magnet attached to the rotating shaft 4, which is tightened to the tip of the compressor impeller 12 with a nut 41 so as to be fixed to the rotating shaft 4. The magnet 52 has a protective ring 53 made of a thin non-magnetic material on its outer peripheral surface, and is configured to prevent the detection permanent magnet 52 from being damaged by centrifugal force even when the turbocharger is driven to rotate at an extremely high speed. and,
The detection permanent magnet 52 is magnetized so as to correspond to the polarity and magnetic pole direction of the permanent magnet of the rotor 3 and to exhibit the same radial distribution of lines of magnetic force.

A magnetic sensor 62 has a detection coil inside and detects changes in the magnetic field of the rotating permanent detection magnet 52, and the detected signal is transmitted to a control device (not shown).

In the third embodiment configured in this way, in the same way as the operation of the first embodiment, changes in the magnetic field by the detection permanent magnet 52 corresponding to changes in the magnetic field during rotation of the rotor 3 can be detected, Furthermore, the shielding plate 8 can shield the magnetic field from the rotor 3 and stator 7, and a detection signal with a high S/N ratio can be obtained.

FIG. 4 is an explanatory diagram showing a fourth embodiment of the present invention, and shows an example in which a detecting magnetic body having a protrusion is provided between a compressor impeller and a tightening nut, and is the same as FIG. 2. The parts are given the same reference numerals.

In FIG. 4, reference numeral 54 denotes a ring-shaped detection magnetic body attached to the rotating shaft 4, and is fastened to the tip of the compressor impeller 11 with a nut 41 so as to be fixed to the rotating shaft 4. A protrusion 55 protruding in the radial direction corresponding to the magnetic pole position of the permanent magnet of the rotor 3 is provided on the outer circumference of the detection magnetic body 54.

In the fourth embodiment configured in this way, when the compressor impeller 11 and the rotor 3 are rotationally driven, the magnetic field is increased every time the projection 55 of the detection magnetic body 54 passes near the magnetic sensor 61. The rotational position of the magnetic poles of the rotor 3 is detected by sensing the change in the magnetic pole and emitting a detection signal.

Note that FIG. 5 is a perspective view showing a seat nut provided with a protrusion, and a similar effect can be obtained by using the illustrated seat nut made of a magnetic material in place of the detection magnetic material 54 and nut 41. That's what you get.

FIG. 6 is an explanatory diagram showing a fifth embodiment of the present invention, in which the spacer or rotor portion is treated with different light reflectances, and the rotor is rotated by changing the reflectance using an optical fiber. This is to detect. In the figure, a spacer 21 is provided between the rotor 31 and the compressor impeller 11, and is fixed on the rotating shaft 4 together with the rotor 31 and the compressor impeller 11 by a nut 41.

As shown in FIG. 6(b), the outer circumferential surface of the spacer 21 is coated with white and black paint, or smooth plating and non-reflective etching so that the reflectance of light is different. Painting or the above treatment is done on the rotor 31.
Processed to correspond to the direction of magnetization of the magnetic poles. Reference numeral 9 denotes an optical fiber that detects changes in the light reflectance of the outer peripheral surface of the spacer 21 and sends signals to a control device (not shown). Note that 10 is a seal ring that prevents exhaust gas from entering from the turbine side.

Further, the rotor 31 is a rotor that is magnetized and whose side surfaces are surface-treated to have different reflectances depending on the direction of the magnetic poles, and changes in the reflectance are detected by the optical fiber 91. Therefore, the change position of the magnetic pole of the rotor can be detected by either the combination of the spacer 21 and the optical fiber 9 or the combination of the rotor 31 and the optical fiber 91.

In the fifth embodiment, there is no need to attach extra parts to the rotating system, and there is little reduction in the output signal due to the effects of oil splash or dust caused by high-speed rotation, so the system is stable over a long period of time. You will get a signal.

Although the present invention has been described above with reference to the above embodiments, various modifications can be made within the scope of the present invention, and these are not excluded from the scope of the present invention.

(Effects of the Invention) According to the present invention, the rotating part of the turbocharger is provided with the detection means corresponding to the magnetic pole position of the permanent magnet of the rotor, and the fixed part is provided with the detection means that can freely detect the rotational position of the detection means. In addition, since a shielding means is provided to shield the detected means and the detection means from adverse influences from the outside, the magnetic pole position of the rotor can be detected accurately. This has the effect of providing a detection signal.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram showing a first embodiment of the present invention, Fig. 2 is an explanatory diagram showing a second embodiment of the invention, and Fig. 3 is an explanatory diagram showing a third embodiment of the invention. , FIG. 4 is an explanatory view showing the fourth embodiment of the present invention, FIG. 5 is a perspective view of the seat nut, and FIG.
The figure is an explanatory diagram showing a fifth embodiment of the present invention. 1.11,12. ...Compressor impeller, 3...
- Rotor, 4... Rotating shaft, 5, 52... Permanent magnet for detection, 6.61.62... Magnetic sensor, 8... Shielding plate, 51... Thin layer, 54...・Magnetic material for detection, 9°9
1...Optical fiber. Patent applicant Isu-X Automobile Co., Ltd.

Claims (1)

[Claims] In a turbocharger with a rotating electrical machine, the rotating shaft of which is driven by exhaust energy of an internal combustion engine is provided with a rotor having a permanent magnet, a permanent magnet for detection corresponding to the magnetic pole position of the permanent magnet is provided on the rotating shaft. A rotating electric machine, further comprising: a detection means for detecting the position of the magnet to be detected when it rotates; the fixed part further includes a shielding means for shielding the detection operation of the detection means from the influence of an external magnetic field. With turbocharger.