JPS5912873B2 - Engine ignition signal generator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an engine ignition signal generating device used in a non-contact ignition device or the like.

As is well known, this type of conventional device includes a rotor that is fixed to a cylindrical body that is loosely fitted to a rotating shaft, and has magnetic poles around it that are equal to the number of cylinders, and as the rotor rotates, the magnetic poles approach and oppose each other.
A magnet generator is constituted by a stator having separate magnetic poles spaced apart from each other and a permanent magnet that allows a magnetic flux to flow through each magnetic pole to a signal coil.

On the other hand, in order to adjust the ignition timing of the engine according to the engine speed, a governor device is installed which rotatably connects the rotor to the rotating shaft.

By the way, since the rotor is loosely fitted to the leading edge of the rotating shaft, the rotor also becomes eccentric due to the eccentric rotation of the rotating shaft.As a result, the relative gap between each magnetic pole varies depending on the engine speed, resulting in optimal ignition. Time characteristics cannot be obtained.

In addition, torque fluctuations based on changes in the angular speed of the engine are transmitted to the cylinder and rotor through the governor weight and weight pins that constitute the governor device, and the ignition timing also fluctuates.

In view of the above-mentioned drawbacks, this invention aims to shorten the axial dimension of the rotating shaft by forming an inductor on the rotary bed plate constituting the governor device, thereby stabilizing the engine ignition timing. A signal generator is provided.

The embodiment shown in FIGS. 1 to 3 will be described below.

In the figure, 1 is a housing of a power distribution device, 2 is a rotating shaft supported by this housing 1 via a bearing 3, 4 is a cylinder made of a magnetic material loosely fitted to this rotating shaft 2, and 5 is rotation axis 2
6 is a spindle fitted to this governor plate 5, 7 is a governor weight loosely fitted to this spindle 6, 8 is a weight pin fitted to this governor way), 9 is a cylinder A rotary base plate made of a magnetic material is fixed to the body 4 and has a guide elongated hole 10 that engages with the weight pin 8. Inductors 11 are formed in four places around the base plate 10 at right angles. , 12 is a bowl-shaped fixed base plate fixed near the opening of the housing 1 with a screw 13; 14 is a first magnetic path plate fitted to the fixed base plate 12 via a sleeve bearing 15; 16 is this first
The second magnetic path plate holds the ring-shaped permanent magnet 17 between the two magnetic path plates 14, and includes an induced element 18 that can face the inductor 10 of the rotary base plate 9 with a radial gap therebetween. It is formed.

A bobbin 19 is held on the fixed base plate 12 via a holder 20, and a signal coil 21 is wound around the bobbin.

The operation of this embodiment is as follows: First, the rotary shaft 2 is rotationally driven by the engine, and the governor base 5, spindle 6, governor way)? The rotary base plate 9 is rotated via the weight pin 8.

When the inductor 11 of the rotating base plate 9 approaches, completely opposes, and separates from the inductor 18 of the second magnetic path plate 16, in this state, the permanent magnet 17 causes the second Magnetic path plate 16→
Induced element 18 → Inductor 11 → Rotating base plate 9 → Screw body 4 → Fixed base plate 1.2 → Sleeve bearing 15 → First magnetic path plate 1
The amount of magnetic flux Φ flowing through 4 changes.

Therefore, since the amount of magnetic flux passing through the signal coil 21 changes, an ignition signal voltage is induced in the signal coil 21 based on this change in magnetic flux, and this signal voltage is applied to the input section of a non-contact semiconductor ignition device (not shown). The engine ignition timing is determined by the engine ignition timing.

By the way, when the governor advance device operates according to the engine rotation speed, the rotary base plate 9 is rotated by a predetermined angle in the rotational direction with respect to the rotary shaft 2, and as a result, the inductor 11 and the induced element 1
Since the operation of approaching, completely opposing, and separating from the signal coil 8 becomes faster, the phase of the signal voltage induced in the signal coil 21 advances, and the ignition timing is advanced.

In this embodiment, by simply forming the inductor 11 on the rotary base plate 9, which is one component of the governor advance device, the entire device is simple and inexpensive, and the axial dimension of the device can be greatly shortened. .

That is, the rotor having a convex portion formed by a process requiring skill such as hole drilling and milling from a round bar, which is conventionally well known, can be eliminated, and furthermore, this rotor can be loosely fitted into the cylinder body 4. This also eliminates the need for assembly work.

Furthermore, since this rotor, which is relatively heavy, is not loosely fitted into the leading edge of the cylinder 4, eccentric rotation of the cylinder 4 is almost completely eliminated, and therefore the rotary base plate 9 can be rotated smoothly without eccentricity. Because of the rotation, the signal voltage induced in the signal coil 21 is stable without being disturbed, and the engine ignition timing is stabilized.

Further, a magnetic circuit including the signal coil 21, the permanent magnet 17 for the signal coil 21, and the first and second magnetic path plates 14, 16 is located inside the housing 1, and the signal coil 21, the permanent magnet 17, First and second magnetic path plates 14.16
Since the fixed base plate 12 holding the ignition voltage is fixed to the housing 1 so as to cover the opening O portion of the housing 1, the ignition voltage is transferred to the first and second magnetic path plates 14,
Even if the ignition voltage leaks to the signal coil 16 and attempts to disturb the signal voltage induced in the signal coil 21, there is no problem because the ignition voltage is shielded by the fixed base plate 12 and grounded through the housing 1.

Furthermore, since the rotary base plate 9 constitutes a part of the magnetic circuit, the hunting phenomenon between the guide elongated hole 10 of the rotary base plate 90 and the weight pin 8, which conventionally occurred, is caused by the weight pin 8 on the rotary base plate 9. This is solved because they are attracted and come into sliding contact.

Although the above embodiments have been described using a magnet generator as a signal generator, it can be applied to any type of photoelectric type or reed switch type ring.

As described above, the present invention makes it possible to eliminate the conventionally known rotor by forming an inductor that cooperates with a signal generator to generate an ignition signal output on the rotary base plate, which is a component of the governor device. By eliminating the rotor and providing a rotary table plate with an inductor formed at the bottom of the cylinder, the eccentricity of the cylinder can be completely eliminated, resulting in a highly accurate and stable ignition signal output.

Further, the number of parts can be reduced, the axial dimension of the device can be shortened, and as a result, a simple and inexpensive device can be provided.

Furthermore, since the rotary base plate constitutes a part of the magnetic circuit, it is possible to prevent hunting between the guide slot of the rotary base plate and the weight pin, which conventionally occurs.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of the present invention, FIG. 2 is a plan view of the rotary base plate 9, and FIG. 3 is a perspective view of the rotary base plate 9. In the figure, 1 is the no-using, 2 is the rotating shaft, 4 is the cylinder,
5 is a governor plate, 6 is a spindle, 7 is a governor weight, 8 is a weight pin, 9 is a rotary base plate, 10 is a guide slot, 11 is an inductor, 12 is a fixed base plate, 14 is a first magnetic path plate , 16 is a second magnetic path plate, 17 is a permanent magnet, 18 is an inductor, 19 is a bobbin, and 21 is a signal coil. Note that the same reference numerals in each figure indicate the same parts.

Claims (1)

[Claims] 1. A rotating shaft driven by an engine, a governor plate fixed to this rotating shaft, a governor weight supported by this governor plate and capable of flying out in response to the rotational force of the rotating shaft,
A spring stretched between the governor weight and the governor plate, a cylindrical body made of a magnetic material loosely fitted to the rotating shaft, and a weight pin fixed to the lower part of the cylindrical body and engaged with the governor weight. A rotating base plate made of a magnetic material and having a guide slot and an inductor, forming a magnetic circuit extending from the cylindrical body to the inductor via the guide slot, and located above the rotating base plate; An engine ignition signal generation device comprising a signal generator that generates an ignition signal output in cooperation with the inductor.