JPH026283Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a variable inertia mass type flywheel device that suppresses fluctuations in the output torque of the output shaft of an engine, particularly in a sporty type vehicle.

In general, in internal combustion engines such as gasoline engines and diesel engines, the only stroke that produces output is the explosion stroke, and the exhaust, intake, and compression strokes consume power, so the rotation of the crankshaft is difficult to smooth. Therefore, the number of cylinders is increased and the strokes of each cylinder are combined evenly, but this alone is not sufficient, so a flywheel 2 is installed at the rear end of the crankshaft 1 as shown in Fig. 1.
The rapid rotational force of the explosion process is stored in the flywheel 2, and rotation is made smooth during the other processes as well.

By the way, the conventional flywheel 2 is disc-shaped, and for example, the flywheel 2 is often made thicker at the circumference to increase the inertia as much as possible and to reduce the weight. There is. However, in the conventional configuration described above, the weight of the flywheel 2 was constant, so when the weight of the flywheel 2 is relatively large, it is easy to suppress fluctuations in the output torque in the low rotation range of the engine. While it can improve stability, in a sporty type vehicle that aims to quickly start up the engine rotation by changing gears and improve vehicle acceleration, the inertia force due to the rotation of the flywheel 2 acts as resistance. Therefore, there is a problem that it is difficult to improve acceleration performance, and there is also a problem that the braking effect of the engine brake becomes worse when the engine speed is reduced.

This idea was made in view of the above points,
The purpose is to effectively suppress fluctuations in engine output torque in the low rotation range, especially in sporty-type vehicles, as well as improve engine acceleration performance during gear shifts and increase the braking effect of engine braking. An object of the present invention is to provide a variable inertial mass type flywheel device that can perform a variable inertial mass type flywheel device.

This invention will be described below with reference to embodiments shown in the drawings. 2 to 4 show an embodiment of this invention, and 11 is a crankshaft (output shaft) of the engine. A main flywheel 12 is connected to the rear end of the crankshaft 11. The main flywheel 12 is a disc-shaped member, and its central portion is attached to the rear end surface of the crankshaft 11 via an attachment 14 with a plurality of bolts 13 . Furthermore, a bent edge 15 is formed on the outer circumference of the main flywheel 12 and is bent inward. An inclined surface 16 is formed at the base end of the inner surface of the bent edge 15, and a ring gear is provided on the outer peripheral surface of the bent edge 15. Further, a sub flywheel 17 is provided inside the main flywheel 12 so as to face the main flywheel 12. This sub-flywheel 17 is a substantially ring-shaped member, and one end surface side of this sub-flywheel 17 has a bent edge 15 of the main flywheel 12.
A ring-shaped guide groove 19 is formed on the insertion portion 18 to be inserted into the inner side of the insertion portion 18 and the other end surface thereof. Furthermore, a ring-shaped protrusion 21 is formed on the inner circumferential surface 20 of the sub-flywheel 17, and a ring-shaped elastic body 22 made of heat-resistant rubber or the like is formed on the main flywheel 12 side of the protrusion 21. The outer peripheral surface is fixed by baking or other means. Further, the inner peripheral surface of this elastic body 22 is fixed to the outer peripheral surface of a cylindrical support member 23 by means such as baking. This support member 23 is rotatably attached to the outer peripheral surface of an attachment 14 at the rear end of the crankshaft 11 via a ball bearing 24. Further, a spring receiver 26 is attached to the end surface of the supporting member 23 on the side opposite to the main flywheel 12 side by a plurality of bolts 25 . Furthermore, a disc spring (spring member) is provided between the spring receiver 26 and the convex portion 21 of the sub flywheel 17.
27 is disposed, and the biasing force of the disc spring 27 keeps the sub flywheel 17 pressed against the main flywheel 12 at all times. Note that the insertion portion 18 of the sub flywheel 17
An inclined surface 28 facing the inclined surface 16 of the main flywheel 12 is formed on the outer peripheral edge of the tip of the main flywheel 12, and a contact body 29 such as a clutch facing material is attached to this inclined surface 28. The main flywheel 12 and the sub flywheel 17 come into contact with each other via the body 29. Further, the tip of an electromagnet (operating section) 30 is inserted into the guide groove 19 of the sub flywheel 17, and when the electromagnet 30 is not energized, the sub flywheel 17 is attached to the disk spring 27. It is held in a state where it is pressed against the main flywheel 12 side by force. Therefore, the sub flywheel 17 is connected to the main flywheel 12, and as the crankshaft 11 rotates, both the main and sub flywheels 1
2 and 17 rotate integrally. A base end portion of the electromagnet 30 is attached to a fixed portion such as a crankcase 31, for example.

Next, FIG. 3 shows a control circuit, and the electromagnet 30 shown in FIG. 2 is turned on and off by a control unit 32 such as a microcomputer.
It is becoming more and more common. A rotation speed detection circuit 33 for detecting the rotation speed of the engine is connected to the control section 32, and a detection signal from the rotation speed detection circuit 33 is input to the control section 32. Further, numeral 34 denotes a shift discrimination circuit for detecting a gear shift, and this shift discrimination circuit 34 outputs a discrimination signal indicating the presence or absence of a gear shift to the control section 32.

Next, the operation of this device configured as described above will be explained. The control unit 32 receives the engine rotation speed input from the rotation speed detection circuit 33 and the shift determination circuit 3.
Based on the discrimination signal input from 4, the process shown in the flow chart shown in FIG. 4 is performed to change the energization state of the electromagnet 30, thereby changing the inertial mass of the flywheel. The operation will be described below with reference to the flowchart shown in FIG. First, step
At S1, the engine speed is A (for example,
1500 rpm) or higher, that is, whether the engine is in the high rotation range. If the determination in step S1 is ``YES'', the process proceeds to step S2 and the control unit 32
A flag provided in a predetermined memory area is set. Then, proceed to step S3 and set the electromagnet 3.
0 is energized. When this electromagnet 30 is energized, the sub flywheel 17 is attracted to the electromagnet 30,
The sub flywheel 17 moves to the left in FIG. 2 against the biasing force of the disc spring 27. Therefore, since the sub flywheel 17 is separated from the main flywheel 12, only the main flywheel 12 rotates as the crankshaft 11 rotates. Therefore, in this case, the crankshaft 11
Since the inertial mass generated by the engine can be reduced, it is possible to improve the acceleration performance in the high engine rotation range (Arpm or higher) and the braking effect of the engine brake.

On the other hand, if the determination in step S1 is "NO", the process proceeds to step S4, where it is determined that the engine speed is B (for example, 1000 rpm) or higher. If "YES" is determined in this step S4, that is, the engine speed is greater than or equal to B and less than or equal to A, that is, the engine is accelerating, the process proceeds to step S5, where it is determined whether or not a gear shift has been performed. Ru. If the determination in step S5 is ``YES'', the process advances to step S6 and the electromagnet 30 is energized. In other words, the same process as in step S3 above is performed, and the inertial mass generated in the crankshaft 11 can be reduced. Therefore, it is possible to improve acceleration performance when a gear shift is performed when the engine speed is greater than or equal to B and less than or equal to A.

Incidentally, in a sporty type vehicle, downshifting is often used to speed up the engine rotation and improve the acceleration of the vehicle. For this reason,
Even if the gear shift is a downshift, the sub flywheel 17 is separated from the main flywheel 12,
By reducing the moment of inertia of the flywheel, the engine rotation is quickly started after the sub-flywheel 17 is separated, and the acceleration performance of the vehicle is improved.

On the other hand, if the determination in step S4 is "NO", the process proceeds to step S7 where the engine is in an idle state and the flag is reset.
Then proceed to step S8 and set the secondary flywheel 1.
7 is connected to the main flywheel 12 or not. "NO" in this step S8
If it is determined that the electromagnet 3 is
0 is no longer energized. Therefore, the sub flywheel 17 is held pressed against the main flywheel 12 by the biasing force of the disc spring 27. Therefore, the sub flywheel 17 is connected to the main flywheel 12 and the crankshaft 11
As the main and sub flywheels 12 rotate,
Since the crankshaft 17 rotates integrally, the inertial mass generated in the crankshaft 11 can be increased. Therefore, it is possible to effectively suppress fluctuations in the output torque in the low engine speed range (below B rpm), and it is possible to improve driving stability and fuel efficiency.

Note that if the determination in step S5 is "NO", the process advances to step S10, where it is determined whether the flag is set. If it is determined as “YES” in this step S10, the process proceeds to the above step S4.
Returns to step S8, and if the determination is “NO”, the process returns to step S8 above.
Return to Also, if you select "YES" in step S8 above,
If it is determined that this is the case, or after the processing in step S9 is completed, the process returns to step S1.

As detailed above, according to this invention, the moment of inertia can be increased by connecting the main flywheel and the auxiliary flywheel in the low engine speed range, so fluctuations in the output torque generated in the crankshaft can be reduced. In addition to effectively suppressing engine speed, the moment of inertia can be lowered by separating the main flywheel and auxiliary flywheel when changing gears at high engine speeds, improving engine acceleration performance and reducing engine braking. A variable inertial mass type flywheel device that can enhance the braking effect can be provided.

[Brief explanation of the drawing]

Figure 1 is a perspective view of a conventional flywheel;
Figures 2 to 4 show an embodiment of this invention, with Figure 2 being a vertical sectional view of the main parts, Figure 3 being a schematic configuration diagram showing the control section, and Figure 4 explaining the operation. This is a flowchart for 11...Crankshaft (output shaft), 12...
... Main flywheel, 17 ... Sub-flywheel, 30 ... Electromagnet (operation section), 32 ... Control section,
33...Rotation speed detection circuit, 34...Shift discrimination circuit.

Claims (1)

[Scope of utility model registration request] A flywheel whose inertial mass can be varied by connecting or separating a main flywheel connected to an output shaft of an engine and a sub-flywheel provided opposite to the main flywheel; an operating section that operates in the direction of separating the gear; a shift determining section that detects a gear shift; and when a gear shift is detected by the shift determining section, the operating section causes the sub flywheel to shift from the main flywheel to the main flywheel. A variable inertia mass type flywheel device comprising: a control section that switches to a state in which only the main flywheel rotates while being separated from the wheel.