JPS616446A - Revolution-variation absorbing apparatus for engine - Google Patents

Abstract

PURPOSE:To improve the revolution-variation absorbing action by offsetting the magnetic-force action immediately after the time when the magnetic-force action becomes max and preventing the reverse action of the magnetic force, in an apparatus for absorbing the revolution variation of an engine by the magnetic force. CONSTITUTION:Permanent magnets 4a and 4b are arranged with the S poles outside on a diameter line of a flywheel 3. Further, permanent magnets 4c and 4d are arranged with the N poles outside on another diameter line. A pair of permanent magnets 6a dna 6b having electromagnetic coils opposed to the permanent magnets 4a-4d are arranged. Position marks 9a and 9b are marked,and a sensor 10 for detecting the position marks is installed. The sensor 10 detects the time when the permanent magnets 4a-4d are opposed to the magnets 6a and 6b. Electromagnetic coils 7a and 7b are operated by the detection signal, and each magnetic force of the magnets 6a and 6b is offset by the action of the electromagnetic coils 7a and 7b.

Description

DETAILED DESCRIPTION OF THE INVENTION 1. OBJECTS OF THE INVENTION (1) Field of Industrial Application The present invention relates to an engine rotational fluctuation absorbing device, and particularly to a device for absorbing rotational fluctuations of a resin body using magnetic force.

(2) Conventional technology In engines with a relatively small number of cylinders, about 1 to 4 cylinders,
The rotational fluctuations of the engine body due to the cycles of suction, compression, explosion, and exhaust are a major cause of idle vibration and noise. There is a technology disclosed in Utility Model Application Publication No. 1984-1944 that absorbs such rotational fluctuations of the engine body using magnetic force. In this conventional technology, permanent magnets are provided in the engine body and the flywheel, respectively, and both permanent magnets are attached to the engine body and the flywheel. The attraction and repulsion forces of the magnet provide the flywheel with torque that offsets rotational fluctuations in the engine body.

(3) Problems to be Solved by the Invention However, in the above-mentioned conventional technology, immediately after an attractive force or a repulsive force is generated between both permanent magnets in response to the rotational movement of the flywheel, a repulsive force is generated on the contrary. Or a suction force is generated. Second, for example, immediately after the speed-increasing torque is applied to the flywheel, the decelerating-side torque is applied to the flywheel, and the effect of absorbing rotational fluctuations in the engine body is halved.

The present invention was made in view of the above-mentioned circumstances, and it is possible to effectively absorb rotational fluctuations of the engine body by using an electromagnet to generate a magnetic flux that cancels the magnetic flux of one of the permanent magnets. The purpose of the present invention is to provide an engine rotational fluctuation absorption device.

B. Structure of the Invention (1) Means for Solving the Problems According to the present invention, a permanent magnet is fixedly arranged on one of the engine body and the flywheel, and the other is set at a crank angle at which rotational fluctuations of the engine body are affected. a permanent magnet that generates a magnetic flux to give the flywheel a rotational torque in a direction that absorbs the rotational fluctuation due to an attractive force or a repulsive force with the permanent magnet, and an electromagnet that generates a magnetic flux in a direction that cancels the magnetic flux by excitation. is fixedly placed.

(2) Effect A mutual attraction or repulsion is generated between the permanent magnet on the flywheel side and the permanent magnet on the engine body side, and when the force reaches its maximum as the flywheel rotates, one side The magnetic flux of the permanent magnet is canceled by the electromagnet.

(3) Example Below, an example in which the present invention is applied to a four-cylinder engine will be explained with reference to the drawings. First, in FIG. 1, a flywheel 3 is fixed to a crankshaft 2 of an engine body 1. By applying torque to the flywheel 3 by the rotational fluctuation absorbing device according to the present invention, 10 rotational fluctuations in the engine body are absorbed.

FIG. 2 shows the rotational fluctuations that occur in the engine body 1 of a 1- and 4-cylinder engine. That is, when the crank angle is .theta.1, .theta., the rotational fluctuation is on the negative side, and when the crank angle is 02.degree..theta., the rotational fluctuation is on the positive side.

Furthermore, the angles between θ1 and 01 and between θ2 and 04 are 90 degrees.

To explain the structure for absorbing such rotational fluctuations of the engine body 1, first, a pair of permanent magnets 4a are placed on the periphery of the flywheel 30 on one diameter line of the crankshaft 2.
4b is fixedly arranged, and a pair of permanent magnets 4c, 4d are fixedly arranged on one diameter line different from the -diameter line. Moreover, one of the permanent magnets 4 a and 4 b is arranged so that the outer side along the radial direction of the flywheel 30 becomes the S pole, and the other permanent magnets 4 c and 4 d are arranged so that the outer side along the radial direction of the flywheel 3 becomes the S pole. It is arranged so that the side becomes the N ridge.

On the other hand, a pair of yaws 5a and 5/l facing the outer peripheral edge of the flywheel 3 are fixedly disposed on the engine body 1 on one diameter line of the flywheel 3. Moreover, each yoke 5a,
, 5b has a permanent magnet 6a on the opposite side of the flywheel 3.
, 6b are adjacent to each other, and electromagnets 7a, 7h are adjacent to each permanent magnet 6a, 6b on the side opposite to the yokes 5σ, 5h. Each permanent magnet 6a, 6b has a yoke 5a, 5h.
The electromagnet γa is arranged so that the side thereof becomes, for example, the north pole.

7b is arranged 6 so as to generate a magnetic flux Φ2 in a direction that cancels 1 of the magnetic flux generated by each of the permanent magnets 6a and 6h. Moreover, the magnetic flux Φ2 due to the electromagnets 7a and 7b is the permanent magnet f3a,
5h of magnetic flux Φ.

In the flywheel 3, two pairs of permanent magnets 4a
, 4b:4c, 4d have an angle θ2 to θ1 between them.
They are arranged to form an angle that is less than . That is, when one permanent magnet 4a, 4b is at an angle θ1 with each yoke 5a, 5b on the rear side along the rotation direction 8 of the flywheel 30, the other permanent magnet 4c, 4d is in the rotation direction 8. In direction 8? 85 behind the permanent magnets 4a and 4h and at an angle 02 between each yaw 5 (Z, 5/l).

A position mark 9a is fixedly provided on the periphery of the flywheel 30 at a position that precedes the permanent magnet 4a by an angle α along the rotational direction 8, and is located one angle α ahead of the permanent magnet 4C along the rotational direction 8. A position mark 9h is provided at a position preceding by +, >:l'N. Also,
Each of the position marks 9 is provided on the engine body 1 at a position forming an angle α with the yoke 5α on the front side in the rotational direction 8.
A sensor 10 is arranged to detect a and 9b. This sensor 1° can detect each position mark 9a, 9b when the position mark 9a, 9b comes to a position facing each other. Therefore, it is determined that one set of permanent magnets 4'a and 4b have come to a position facing the yokes 5a and 5b by detecting one position mark 9σ with the sensor 1o, and the other set of permanent magnets It is determined that the yokes 4C and 4d have come to the positions facing the yokes 5σ and 5h by detecting the other position mark 9b with the sensor 10.

The detection signal of the sensor 10 is input to the control circuit 12 connected to the battery 11, and when the control circuit 12 receives the signal indicating that the position marks 9a, 9b have been detected, the control circuit 12 detects the position marks 9a, 9b. It operates to excite. That is, each electromagnet 7a, 7. b is excited as shown in FIG.

Next, to explain the operation of this embodiment, the sensor 1σ
detects the positive 7 mark 9a, , 9h and
・℃・Sometimes the electromagnets 7a and 7h are demagnetized,
The surface facing the flyboil 3 with a yaw of 5σ and 5h is N-off, and a permanent magnet 7 (1, '1's 18 east ΦI) is generated (・ru. In this state, the flywheel 3, one set of permanent magnets 4a.

When 4h comes close to yokes 5θ and 5bK, permanent magnet 4
A suction force υ1 acts between σ, 4h and the yokes 5a and 5b, and a speed-increasing torque is generated on the flywheel 3.

One set of permanent magnets 4a and 4b is a yoke 5a.

When the position corresponding to 5h is reached: ``In other words, when one position mark 9a is detected by the sensor 1o, each electromagnet 7 (L, 7h) is excited for a short time. , a magnetic flux Φ2 is generated that cancels the magnetic flux Φ of the permanent magnets 6α, 6h.Therefore, immediately after the permanent magnets 4a, 4b pass the yokes 5a, 5b, the attractive force between the permanent magnets 4α, 4h and the yokes 5a, 5b increases. This makes it possible to avoid applying deceleration-side torque to the flyboil 3.

In the same manner as described above, the other set of permanent magnets 4c.

When 4d approaches yaw 5σ and 5h, a decelerating torque is applied to the flyboil 3 due to mutual repulsion, and the permanent magnets 4C and 4d act as the yoke 5a.

When it reaches 5b, electromagnets 7a' and 7h are excited,
Immediately after the permanent magnets 4c and 4d pass the yaw 5 (2.5/l), it is possible to avoid applying speed-increasing torque to the flywheel 3 due to repulsive force.

The rotational fluctuation characteristics due to such magnetic force are shown as a curve 13 shown by the fruit and gland in FIG. 4. As is clear from Fig. 4, the rotational fluctuation due to magnetic force has the characteristic of absorbing the 10-rpm fluctuation of the engine body shown in Fig. 2, and the 10-rpm fluctuation of the engine body can be effectively suppressed. .

Here, the rotational fluctuation due to the magnetic magnet when electromagnets 7σ and 7b are not used is shown by the curve 14 shown by the broken line in Fig. 4.
So, each crank angle θ1. θ2. At θ3° θ4, the acceleration side changes to the deceleration side. °C is the deceleration ([1] becomes reversed to the speed increase side. This reversal partial force ・As in the present invention, the electromagnet 7
This problem is solved by providing the parts a and 7b, and the 10 rotation fluctuation of the engine body can be effectively suppressed.

As another embodiment of the present invention, the magnetic flux Φ2 caused by the electromagnets 7a and 7h may be set larger than the magnetic flux Φ1 caused by the permanent magnets 6a and 6b. In this way, the electromagnets 7a and 7b
By excitation, the polarity of the yokes 5a and 5b is reversed, so that an effective torque can be generated in the torque portion that was canceled in the previous embodiment, as shown by the dashed line curve 15 in FIG. That is, one set of permanent magnets 4a.

4b, a speed-increasing torque is applied to the flywheel 3 even after passing through the yokes 5a, 5b, and the part of the other set of permanent magnets 4c, 4cL is applied to the yoke 5a.

Even after passing for 5 hours, the torque on the deceleration side is transferred to the flywheel 3.
can be given to

Effects of the C0 Invention As described above, according to the present invention, a permanent magnet is fixedly arranged on one side of the engine body and the flywheel, and on the other side,
a permanent magnet that generates a magnetic flux for applying a rotational torque in a direction to absorb the rotational fluctuation to the flywheel by an attractive force or a repulsive force with the permanent magnet at a crank angle at which the rotational fluctuation of the engine body becomes a dog; An electromagnet that generates a magnetic flux in a direction that cancels the magnetic flux by excitation is fixedly arranged, so the permanent magnet on the flywheel side and the permanent magnet on the engine body side generate an increase in the flywheel due to mutual attraction or repulsion. In addition to carrying the torque on the speeding or decelerating side, the magnetic flux of the electromagnet cancels the magnetic flux of the negative permanent magnet, and the torque is reversed from the speed increasing side to the decelerating side, or from the decelerating side to the speed increasing side. It can prevent slippage and effectively absorb rotational fluctuations of the engine body.

4 A schematic explanatory drawing of the drawing (1) This shows an embodiment of the present invention applied to a 4-cylinder engine.
FIG. 2 is a diagram showing the rotational fluctuation characteristics of the engine body, FIG. 3 is a diagram showing the excitation timing of the electromagnet, and FIG. 4 is a diagram showing the rotational fluctuation characteristics due to the magnet.

1. Engine body, 3. Flywheel, 4a to 4'
cl, 6a, 6b - permanent magnet, 7 a, 7 h - electric (% stone

Claims (1)

[Claims] A permanent magnet is fixedly disposed on one side of the engine body and the flywheel, and the other side has a magnet in the direction of absorbing the rotational fluctuation by attraction or repulsion with the permanent magnet at a crank angle where the rotational fluctuation of the engine body becomes large. A rotational fluctuation absorbing device for an engine, characterized in that a permanent magnet that generates a magnetic flux for applying rotational torque to a flywheel, and an electromagnet that generates a magnetic flux in a direction to cancel the magnetic flux upon excitation are fixedly arranged.