JPH026282Y2 - - 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.

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 stroke is stored in the flywheel 2, and rotation is made smooth during the other strokes.

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. Although stability can be improved, when the engine speed is accelerated, the inertia force due to the rotation of the flywheel 2 acts as resistance, so there is a problem that it is difficult to improve acceleration performance, and when the engine speed is decelerated, the engine There was also the problem that the braking effect of the brakes deteriorated. Furthermore, there was also the problem that engine vibration and noise increased in the high engine speed range.

This idea was made in view of the above points,
The purpose of this is to effectively suppress fluctuations in output torque in the low engine speed range, improve engine acceleration performance and increase the braking effect of engine braking, and improve engine speed in the high engine speed range. An object of the present invention is to provide a variable inertial mass type flywheel device that can reduce vibration and noise and consumes less power.

This invention will be described below with reference to embodiments shown in the drawings. FIG. 2 shows an embodiment of this invention, in which 11 is the 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. This bent edge 1
An inclined surface 16 is formed on the inner surface base end of the bent edge 15, and a ring gear is provided on the outer circumferential surface of the bent edge 15, and a labyrinth seal 17 as a sealing member is provided on the inner circumferential surface of the ring gear. It is being
Further, a sub flywheel 18 is provided inside the main flywheel 12 so as to face the main flywheel 12. This sub-flywheel 18 is a substantially ring-shaped member, and an insertion portion 19 is formed on one end surface side of the sub-flywheel 18 to be inserted inside the bent edge 15 of the main flywheel 12, and an insertion portion 19 is formed on the other end surface side. The outer circumferential surface of a ring-shaped elastic body 20 made of heat-resistant rubber or the like is fixed by baking means. The inner circumferential surface of this elastic body 20 is fixed to the outer circumferential surface of a cylindrical support member 21 by means such as baking. Spline grooves 22 are formed in the axial direction at several locations on the inner peripheral surface of the support member 21. Further, the support member 21 is rotatably attached to the outer peripheral surface of the attachment 14 at the rear end of the crankshaft 11 via a ball bearing 23. A spline convex portion 24 that engages with the spline groove portion 22 is formed on the outer peripheral surface of the outer race portion 24 of the ball bearing 23 . Furthermore, the inner race portion 25 of the ball bearing 23
is attached to the outer peripheral surface of the attachment 14. Reference numeral 26 denotes an oil seal housing 26 fixed to the engine block, and a ring-shaped oil seal 27 is interposed between the oil seal housing 26 and the support member 21. A ring-shaped oil seal 28 is also interposed between 26 and the crankshaft 11. Further, a through hole 29 is bored in the oil seal housing 26, and this through hole 29 is connected to a pipe 30. The space A between the main flywheel 12 and the sub flywheel 18 is the labyrinth seal 1.
7 and the oil seals 27 and 28, the airtightness is maintained. Then, the pipe 3 is placed in the space A.
0. When the negative pressure of the intake manifold, for example, is sent through the through hole 29, the air pressure in the space A decreases, and the sub flywheel 18 is always held in a state where it is attracted to the main flywheel 12 side. . Note that the insertion portion 19 of the sub flywheel 18
An inclined surface 31 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. A contact body 32 such as a clutch facing material is attached to this inclined surface 31. Contact body 3
The main flywheel 12 and the sub-flywheel 18 are in contact with each other via 2. On the other hand, when atmospheric pressure is sent into the space A through the piping 30 and the through hole 29, the air pressure in the space A increases and the sub flywheel 1
8 is held apart from the main flywheel 12. The piping 30 is connected to an electromagnetic valve (not shown), and by controlling this electromagnetic valve, intake negative pressure or atmospheric pressure is selectively sent into the space A. .

Therefore, in the case of the above-mentioned structure, the sub-flywheel 18 is held in a state where it is attracted to the main flywheel 12 side by sending suction negative pressure into the above-mentioned space A in the low rotational speed range of the engine. Therefore, the sub flywheel 18 is connected to the main flywheel 1.
Since both the main and auxiliary flywheels 12 and 18 rotate integrally as the crankshaft 11 rotates, the inertial mass generated in the crankshaft 11 can be increased. Therefore, fluctuations in the output torque in the low engine speed range can be effectively suppressed, and driving safety and fuel efficiency can be improved. Further, in a high rotation range where the engine rotation speed exceeds a certain set value, by opening the space A to atmospheric pressure, the sub flywheel 18 moves to the left in FIG. 2. Therefore, since the sub flywheel 18 is separated from the main flywheel 12, only the main flywheel 12 rotates as the crankshaft 11 rotates. Therefore, in this case, the inertial mass generated in the crankshaft 11 can be reduced, so that the acceleration performance in the high rotational speed range of the engine can be improved and the braking effect of the engine brake can be suppressed. Furthermore, by sending negative pressure or atmospheric pressure into the space A, the sub flywheel 18 is connected to and held by the main flywheel 12 or held apart from the main flywheel 12, so the power consumption for holding it is extremely low. Battery consumption can be suppressed.

As detailed above, according to this invention, it is possible to effectively suppress fluctuations in the output torque in the low engine speed range, and also to improve the acceleration performance of the engine and the control effect of the engine brake. Therefore, it is possible to provide a variable inertial mass type flywheel device that can reduce engine vibration and noise in a high engine rotation range and consumes less power.

[Brief explanation of the drawing]

Figure 1 is a perspective view of a conventional flywheel;
FIG. 2 is a longitudinal sectional view of a main part of a variable inertia mass type flywheel device according to an embodiment of the invention. 11...Crankshaft (output shaft), 12...
...Main flywheel, 18...Sub-flywheel, 27, 28...Oil seal.

Claims (1)

[Scope of utility model registration request] A main flywheel connected to the output shaft of the engine, a sub flywheel installed opposite to the main flyhole and rotatably and movably in the axial direction with respect to the output shaft, and the main flywheel. An airtight space formed by both axially opposing surfaces of the flywheel and the sub-flywheel and a sealing member attached to one of the flywheels and constantly in contact with the other, and this airtight space communicated with the intake manifold to provide the airtight space as described above. The flywheel is characterized by comprising means for connecting the sub-flywheel and the main flywheel by pressing the opposing surfaces against each other, and opening the airtight space to the atmosphere to separate the sub-flywheel from the main flywheel. Variable inertia mass type flywheel device.