JPS591410Y2 - Signal generator for non-contact ignition system - Google Patents

Description

[Detailed description of the invention] This invention is a signal generator for a non-contact ignition system of an engine.
In particular, the present invention relates to an improvement in a signal generator that utilizes a wheel-shaped magnet generator that is directly connected to and driven by the engine crankshaft.

Conventionally, in this type of signal generator, it is difficult to attach a signal generator inside the wheel-type magnet generator, so the signal generator is attached to the outside of the wheel-type magnet generator. Something like this has been proposed as shown in FIGS. 1 to 3.

First, in the one shown in FIG. 1, in order to fix the magnet B and the magnetic pole piece C to the inner circumferential part of the cart body A, a mounting screw D is inserted through the magnetic insulator E to the outer circumference of the cart body A. A magnetic pole for the ignition signal is derived from the magnetic pole, and a generator F for the ignition signal is provided so as to face this magnetic pole.In addition, the one shown in FIG. 2 has a magnetic pole piece C' in contact with the magnet B'. Extend the ignition signal magnetic pole to the outer periphery of the wheel body A' via the magnetic insulator E',
A generator F' for ignition signals is provided so as to face this magnetic pole.

However, in both Figures 1 and 2, magnetic pole pieces c and c' are provided on the inner circumferential surface of magnets B and B', and recently ferrite magnets have been installed in an annular shape on the inner circumferential surface of the wheel body. There was a drawback that it could not be used in a system in which the magnetic pole piece was placed in the magnetic field and did not have a magnetic pole piece.

Therefore, as shown in FIG.
It has been proposed that a hole G is drilled at /, and a generator F// for an ignition signal is provided so that the magnetic flux φ leaking from this hole G interlinks.

However, since the one shown in Fig. 3 utilizes the leakage magnetic flux φ of the ferrite magnet B'', the magnetic flux φ linked to the ignition generator F// is very small. However, when the engine rotational speed is low, the output voltage is low and the semiconductor switching element of the non-contact ignition device cannot be made conductive, which is a serious drawback.

The present invention has been specially devised to address the above points, and utilizes the fact that only a minute portion of a ferrite magnet can be magnetized with opposite polarity to provide an excellent signal generator that can completely eliminate the above drawbacks. That is the purpose of this.

4 and 5 showing embodiments of the present invention. In these figures, reference numeral 1 denotes a bowl-shaped cart body made of a magnetic material such as soft iron, and the central portion of the cart body 1 is 1
A boss fitting 2 to be fitted onto the engine crankshaft (not shown) is fixed to a, and the inner peripheral surface of the cylindrical portion 1b has four ferrites provided with radial magnetic poles. Magnets 3-1.3-2.3-3.3-4 are arranged in a ring,
It is fixed with adhesive etc.

As shown in the figure, a C-shaped notch groove 1C is bored in the cylindrical portion 1b of the main wheel body 1, and a ferrite magnet is brought into contact with the inner surface including the head 1d surrounded by the notch groove 1C. 3
By magnetizing the minute portion 3-1a of -1 with the opposite polarity to the magnetic pole, the head 1d becomes the outer circumferential minute magnetic pole of the wheel body tubular portion 1C, so that it faces the outer circumferential minute magnetic pole of the head 1d. A generator 4 for ignition signals is provided.

The generator 4 includes a U-shaped generator core 4a and a generator coil 4b wound around the core 4a.

Since the present invention-embodiment is constructed as described above, a large number of iron cores 4b of the ignition signal generator 4 facing the head 1d surrounded by the C-shaped notch groove 1C forming the outer peripheral minute magnetic pole are provided. Since the magnetic fluxes interlink, even if the rotational speed of the cart main body 1 is relatively low, an output voltage strong enough to conduct the semiconductor switching element of the non-contact ignition device can be generated.

As is clear from the above explanation, according to the present invention, a C-shaped notch groove is bored in the cylindrical part of the cart body, and the inner surface including the head surrounded by this notch groove is abutted. By magnetizing a minute portion of the ferrite magnet with opposite polarity, the head becomes a minute magnetic pole on the outer periphery of the cylindrical portion of the wheel body, and a generator for an ignition signal of the engine is provided so as to face the minute magnetic pole on the outer periphery. Therefore, compared to the conventional system shown in Fig. 3, in which the leakage magnetic flux is linked to the generator core, the generator core of the present invention has a significantly larger amount of magnetic flux. Therefore, even if the rotational speed of the engine, that is, the rotational speed of the cart itself, is relatively low, it is not possible to generate an output voltage strong enough to conduct the semiconductor switching element of the non-contact ignition device. can.

In addition, a C-shaped notch groove is bored in the cylindrical part of the cart body, and the head surrounded by the notch groove is used as an outer peripheral minute magnetic pole, so the structure is simple and the manufacturing cost is significant. It also has a significant practical effect of being able to be made more cost-effective.

[Brief explanation of drawings]

1 to 3 are cross-sectional views showing the main parts of a conventional generator of this type, and FIGS. 4 to 6 show a generator according to an embodiment of the present invention. - Sectional view along the Y line, 5th
The figure is a sectional view taken along the line XX in FIG. 4, and FIG. 6 is a plan view showing the main parts of the cart body. In the figure, 1 is the cart body, 1b is its cylindrical part, 1C is a C-shaped notch, 1d is the head surrounded by the notch, 31...
...3-4 is a ferrite magnet, 3-1a is a minute portion magnetized with opposite polarity, and 4 is a generator for an ignition signal.

Claims (1)

[Scope of utility model registration request] A wheel-shaped magnet power generation device comprising a wheel-shaped wheel body made of a magnetic material and a plurality of ferrite magnets fixed annularly to the inner peripheral surface of a cylindrical portion of the wheel body and provided with radial magnetic poles. In the machine, a C-shaped notch groove is bored in the cylindrical part of the wheel body, and a minute portion of the ferrite magnet that is in contact with the inner surface including the head surrounded by the notch groove is placed opposite to the magnetic pole. The non-contact point is characterized in that the head is made into a minute magnetic pole on the outer periphery of the cylindrical part of the wheel body by being magnetized with polarity, and a generator for an engine ignition signal is provided so as to face the minute magnetic pole on the outer periphery. Signal generator for ignition system.