JPH0681898A - Multistep viscous damper - Google Patents

Abstract

PURPOSE:To reduce the cost by forming damping force adjusting slits, so that the slits can be opposed, in a flywheel side plate and a floating plate, and reducing a noise in an engine and a car body. CONSTITUTION:The first flywheel 14 integrally connected to a crankshaft 11, second flywheel 17 pivotally supported to a boss part of the first flywheel 14 through a bearing 16 and a torsion spring 19 between both the flywheels are provided, and in a multistep viscous coupling 18, between a drive side plate 30 in the first flywheel side and a driven side plate 32 in the second flywheel side, a floating plate 33 slid relatively to both these plates is interposed, to form damping force adjusting slits, which can be opposed to each other, in the floating plate 33 and in one of the flywheel side plates 30, 32. In this way, the coupling 18 is made easy to slip or prevented from easily slipping, to adjust viscous torque of oil, and torsional vibration in a total engine speed region can be restricted so as to be small.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-stage viscous damper which is mounted on a flywheel that rotates in the body of an internal combustion engine and which reduces engine vibration caused by fluctuations in torque.

[0002]

2. Description of the Related Art An internal combustion engine, during its operation, carries out an explosion stroke at a constant crank angle for each cylinder. Therefore,
Vertical vibration, rotational vibration around the rotation center line of the crankshaft, and torsional vibration of the crankshaft itself occur in the internal combustion engine body. Here, the vertical vibration applied to the internal combustion engine main body is directly applied to the internal combustion engine main body during the explosion stroke of the combustion chamber, which is a factor of noise of the internal combustion engine main body.
Further, the rotational vibration applied to the internal combustion engine main body is accompanied by the rotational fluctuation generated in the explosive stroke of the cylinders that are dispersed in the longitudinal direction of the crankshaft and face each other. Added as a moment,
It is a cause of noise in the internal combustion engine itself. Further, the torsional vibration of the crankshaft is also transmitted as vibration to the main body of the internal combustion engine via the bearing portion, which causes noise in the main body of the internal combustion engine.

Among these noise factors, the vertical vibration applied to the internal combustion engine body uses a silent shaft that cancels the vertical vibration due to the rotation of the unbalanced mass. It is known that this can be reduced by a rolling moment canceller having an auxiliary flywheel that is reversed with respect to the main flywheel. On the other hand, it is known that the torsional vibration of the crankshaft can be reduced by the crankshaft torsional vibration damper integrally mounted on the crankshaft. When the rotational force of the crankshaft is directly transmitted from the flywheel to the drive wheel side via the clutch, resonance occurs at a resonance point as indicated by reference numeral f1 in FIG. 10, and the crankshaft torsional vibration occurs in the normal rotation range. It is easy to cause engine and vehicle noise due to. Therefore, if the resonance point is brought before the idle range, resonance in the normal rotation range can be prevented, and for this purpose, the flywheel is divided into two parts. Further, it is known that the torsional vibration of the crankshaft has a large amplitude in a low rotation speed region and a small amplitude in a high rotation speed region.
It has the characteristics shown in. Therefore, it is conceivable to mount a damper between the first mass and the second mass in order to reduce the vehicle body noise by reducing the amplitude in the low rotation range. In this case, the amplitude at the resonance point f2 in the low rotation range is relatively reduced as shown by the broken line b, but in this case, the amplitude in the high rotation range becomes high in the comparator. Therefore, the damping rate of the damper is not set to a single value, but the damping rate in the low frequency (low rotation speed) range is set relatively high and the damping rate in the high frequency (high rotation speed) range is set relatively low. As shown in FIG.
It is desirable to obtain the characteristics shown in.

For example, a crankshaft torsional vibration damper as shown in FIGS. 8 and 9 has a first crankshaft integral with a first crankshaft.
A second mass 2 pivotally supported by the first mass 1 via a mass 1 and a bearing 3, a driven plate 4 arranged between the first and second masses, a driven plate 4 and a drive plate 5 on the first mass side. And a hydrocoupling 6 with an AC-DC mechanism provided between the driven plate 4 and the second mass.

In this case, when the torsional vibration of the crankshaft is in the high frequency (high rotational speed) range, the slide stopper 8 slidably supported by the drive plate 5 and the projection 9 of the driven plate 4 are filled. The damper operation is performed by relatively moving within the AC operating angle θ1 against the flow resistance of the oil being stored. On the other hand, when the torsional vibration is in the low frequency (low rotation number) range, the slide stopper 8 is pressed against the projection 9 of the driven plate 4 and the stopper of the drive plate 5 is resisted against the flow resistance of the oil further filled. 1
The damper operation is performed by relatively moving within the DC operation angle θ2 until it comes into contact with 0. When the amplitude is particularly large, the drive plate 5, the slide stopper 8, and the driven plate 4 are integrated with each other, and these elastically deform the torsion spring 7 and relatively change with the second mass 2 to absorb the shock. Operate.

Here, in particular, the damper operation when the slide stopper 8 and the projection 9 of the driven plate 4 relatively fluctuates within the AC operating angle θ1 is performed at a relatively low damping rate.
The damper operation when the slide stopper 8 and the protrusion 9 relatively fluctuate within the DC operating angle θ2 is performed at a relatively high reduction rate, and it is possible to obtain the characteristics shown by the chain line c in FIG. .

[0007]

However, the crankshaft torsional vibration damper as shown in FIG. 8 and FIG. 9 sets the damping rate based on the flow resistance of the oil. There is a problem that high precision is required for setting the throttle amount of the flow path, and many parts are required, and the manufacturing cost is relatively high. An object of the present invention is to provide a multi-stage viscous viscous damper capable of sufficiently reducing the noise of the engine and the vehicle body and reducing the cost.

[0008]

In order to achieve the above-mentioned object, the present invention provides a first flywheel that is integrally connected to a crankshaft of an internal combustion engine to rotate, and a bearing on a boss portion of the first flywheel. A multi-stage viscous cup, which is mounted between the first flywheel and the second flywheel and is pivotally supported via the second flywheel and the clutch flywheel is formed between the first flywheel and the second flywheel based on the viscosity of the oil. The multi-stage viscous coupling has a ring and a torsion spring that absorbs relative rotational displacement between the first flywheel and the second flywheel and transmits an average torque. Between the drive side plate and the driven side plate on the side of the second flywheel, there is a floaty slidable relative to these plates. Gupureto is interposed, characterized in that said floating plate and the slit for mutually opposable damping force adjustment for the one flywheel plate above are formed respectively.

[0009]

The multi-stage viscous viscous coupling here is liable to slip when the damping plate adjusting slits of the floating plate and one flywheel side plate face each other, and the viscous torque transmitted based on the oil viscosity is On the contrary, if both slits deviate from each other, slipping does not occur easily, and viscous torque increases, so when the flywheel receives a small amplitude at high rotation speed (high frequency), it is easy to slip, that is, both slits It is possible to achieve a low damping rate where the viscous torque decreases in opposition to each other, and conversely it is difficult to slip when a large amplitude is received in the low rotation speed (low frequency) range, that is, both slits are offset from each other and the viscous torque increases. It becomes possible to achieve a high damping rate, and the amplitude on the crankshaft side can be restricted to a small value in the entire engine rotation range.

[0010]

1 shows a multistage viscous viscous damper according to the present invention. This multi-stage viscous damper has a crankshaft 11 and a clutch 12 of an engine (not shown).
And is mounted in a two-divided flywheel 13 that is integrally connected to the crankshaft 11 and is used as a crankshaft torsional vibration damper.
Is configured to reduce the torsional vibration of the.

The multi-stage viscous damper has a first flywheel 14 integrally connected to an end portion of a crankshaft 11 and a second flywheel pivotally supported by a boss portion 15 of the first flywheel 14 via a bearing 16. Wheel 17
And the first flywheel 14 and the second flywheel 17
And a multi-stage viscous viscous coupling 18 installed between
The torsion spring 19 is provided between the first flywheel 14 and the second flywheel 17. Moreover, the second flywheel 17 integrally mounts the clutch cover 20 on the side opposite to the clutch 12, and supports the pressure plate 21 in the clutch cover via the diaphragm spring 22. The diaphragm spring 22 also functions as a release lever that operates the pivot ring 24 as a fulcrum, and presses the pressure plate 21 against the clutch plate 23 to release it. The clutch plate 23 that rotates integrally with the output shaft 25 is the second flywheel 1.
The torque transmission is intermittently performed by connecting and disconnecting with the clutch joint surface 26 of No. 7.

Outer peripheral teeth 27 that mesh with a starter (not shown) are formed on the outer peripheral portion of the first flywheel 14, and a torsion spring 19 is supported at a position spaced apart at a predetermined interval on the inner circumference thereof. One end (the front side in FIG. 1) of this torsion spring 19 is the first
It is supported opposite to a spring receiver (not shown) on the flywheel 14 side, and the other end is a spring receiver 17 on the second flywheel 17 side.
1 is supported oppositely.

The multi-stage viscous viscous coupling 18 is the first
A drive rotor 28 integrally attached to the boss portion 15 of the flywheel, a drive side plate 30 supported by the drive rotor, and a driven rotor 31 integrally attached to the central portion of the second flywheel. A driven side plate 32 supported by the driven rotating body, and a driving side plate 30.
And a floating plate 33 that is slidably interposed between the driven plate 32 and the driven plate 32.

Splines 34 and 35, which are long in the longitudinal direction Y of the crankshaft, are formed on the outer peripheral wall of the drive rotor 28 and the inner peripheral wall of the driven rotor 31, in which the drive side plate 30 and the driven side plate 32 are formed. Each is configured to mesh. Moreover, the driven rotary body 31 is formed in the annular hollow body 311 having an opening on the inner peripheral side thereof.
The opening 11 is covered with the annular plate portion 281 of the drive rotor 28 to form an annular chamber B. Note that reference numerals 36 and 37 denote seal rings, and the drive side plate 3 inside the annular chamber B is shown.
0, driven side plate 32 and floating plate 3
The silicone oil filled in the space 3 is prevented from leaking from the sliding contact surface f between the annular hollow body 311 and the annular plate portion 281.

As shown in FIG. 3C, the driving side plate 30 has inner peripheral teeth 301 formed on its inner peripheral edge for meshing with the spline 34, and its outer peripheral edge does not reach the tips of the splines 35. Its outer diameter is formed. As shown in FIG. 3B, the floating plate 33 has a central hole 331 that is loosely fitted in the spline 34, and has an outer diameter that does not reach the tip of the spline 35. Slits 332 having a width C1 relatively wider than the tooth width of the inner circumferential tooth 301 are formed at equal intervals in the circumferential direction. As shown in FIG. 3A, the driven side plate 3
2 is an outer peripheral tooth 32 that meshes with the spline 35 on its outer peripheral edge.
1 is formed, and a center hole 323 that is loosely fitted to the spline 34 is formed, and a slit having a width C2, which is relatively wider than the tooth width of the inner peripheral tooth 301, is formed on the inner peripheral edge thereof at equal intervals in the circumferential direction. 322 is formed. Each plate 30,
32 and 33 are formed in a thin disk shape having a uniform thickness.
As shown in FIG.
0 and the floating plate 33 are superposed on each other.

Between the plates, a pair of large and small rings (not shown) made of ultra-thin steel material for clearance adjustment are interposed between the inner and outer sides of the plates, respectively, so that they are always adjacent to each other. The gap between the plates is kept constant.

The operation of the multi-stage viscous viscous damper as described above will be described.

When the crankshaft 11 rotates,
It is assumed that the average torque is transmitted from the crankshaft 11 to the output shaft 25. In this case, the first flywheel 14 and the second flywheel 17 are relatively rotated in one direction by the rotation angle of the low frequency component (in FIG. 5, 1 / of the average amplitude H ₀ at that time).
2), the torsion spring 19 transmits torque via a spring bearing (not shown) on the first flywheel 14 side and a spring bearing 171 on the second flywheel 17 side. At this time, it can be considered that the second flywheel 17 is held at the rotation angle of the low frequency component and then exhibits the rotation fluctuation rad / sec of the amplitude h ₀ of the high frequency component. When the high-frequency component has an amplitude h ₀ , that is, a small amplitude, the multi-stage viscous viscous coupling 18 keeps slipping easily, as shown in FIG. 6A. Here, the slit 332 of the floating plate 33 and the slit 322 of the driven side plate 32 are opposed to each other, and the ratio in which the overlapping region W1 capable of transmitting the viscous torque transmitted based on the viscosity of oil is kept relatively small increases, A low damping rate is maintained in which the amount of torque transmission is relatively reduced. Therefore, in a high frequency (high rotation speed) range, it is possible to suppress high-frequency torsional vibration in a state of a relatively low damping rate and reduce engine and vehicle body vibration.

On the other hand, in the low frequency range below idle rotation, the first flywheel 14 and the second flywheel 17
Becomes a state in which a relatively large amplitude is received, and the rate at which the fluctuation of the rotation angle of the low-frequency component (in FIG. 5, the outline of the waveform at that time is indicated by a chain double-dashed line and the amplitude is shown as H1) is repeated increases. For this reason, the multi-stage viscous coupling 1
In FIG. 8, the drive side plate 30 and the driven side plate 32 repeat large fluctuations, and as shown in FIG. 6B, the slip is difficult to occur, that is, the slit 332 of the floating plate 33 and the slit 322 of the driven side plate 32 are The ratio at which the overlap region W2, which is largely deviated from each other and can transmit the viscous torque, reaches a relatively large state, increases, and a high damping rate can be achieved. Therefore, the amplitude of the torsional vibration can be suppressed in a relatively high damping state in the low frequency range below the idling rotation, whereby the engine and vehicle body vibration in the low rotation speed range can be reduced.

In the above description, the driven side plate 3
2 and the floating plate 33 have slits 322,
332 is formed, and the ratios of the slits 322 and 332 facing each other are changed, that is, the overlapping regions W1 and W2 capable of transmitting viscous torque are changed between a low rotation range and a high rotation range, and a high damping rate is obtained in the low rotation range. In the high rotation range, the low damping rate was obtained, but instead, the driven side plate 32 was formed into a single disc without slits, and the driving side plate 30 and the floating plate 33 were formed with slits. It is also possible to obtain a high damping rate in the low rotation range and a low damping rate in the high rotation range.
The same effect as the device of 1 can be obtained.

Although there has been no restriction on the relative rotational fluctuation amount between the floating plate 33 and the driven plate 32 in the above description, a stopper 40 is formed on the driven plate 32a as shown in FIG. It may be formed so that the relative variation amount s of the floating plate 33 is regulated by a stopper. In this case, when the stopper 40 is locked to the floating plate 33 and integrally slides with respect to the overlapping area W3 at a low damping rate, the overlapping area at a high damping rate becomes W4 and becomes large, and in particular, at a high damping rate (low rotation speed). (When operating in the range), the damping operation is reliably performed, and the response to the high damping rate is improved.

[0022]

As described above, according to the present invention, when the flywheel receives a small amplitude in a high rotation speed (high frequency) range, it easily slips, that is, floats with one of the first and second flywheels. Both slits with the plate can face each other to achieve a low damping rate in which the viscous torque is reduced, and conversely, in the state where a large amplitude is received in the low rotation speed (low frequency) range, it is difficult to slip, that is, both slits Since it is possible to achieve a high damping rate in which the viscous torque increases by shifting from each other, the torsional vibration on the crankshaft side can be restricted to a small value in the entire engine rotation range, and the noise of the engine and the vehicle body can be sufficiently reduced. , Easy to process and low cost.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view of a multistage viscous viscous damper according to an embodiment of the present invention.

FIG. 2 is a side sectional view of a main part of the viscous damper of FIG. 1 taken along line XX.

3A is a driven side plate in the multi-stage viscous viscous coupling in FIG. 1, FIG. 3B is a floating plate in the viscous coupling, and FIG. 3C is a drive side plate in the viscous coupling.

FIG. 4 is a side view of a driven side plate, a floating plate and a driving side plate in the multi-stage viscous viscous coupling in FIG. 1 in a superposed state.

5 is a first multi-stage viscous viscous coupling shown in FIG.
It is a rotation fluctuation characteristic diagram of a flywheel.

6 (a) is an explanatory view of a low damping rate state of each plate when the multi-stage viscous viscous coupling in FIG. 1 is in a high rotation range, and (b) when the viscous coupling is in a low rotation range. It is explanatory drawing of the high damping rate state of each plate.

FIG. 7 is an explanatory diagram of a damping ratio of each plate in a multi-stage viscous viscous damper as another embodiment of the present invention.

FIG. 8 is a partial cross-sectional view of a conventional crankshaft torsional vibration damper.

9 is a partial side sectional view of the crankshaft torsional vibration damper of FIG.

FIG. 10 is a torsional vibration characteristic diagram of a crankshaft rotation system including a crankshaft torsional vibration damper.

[Explanation of symbols]

 11 crankshaft 14 first flywheel 15 boss portion 15 16 bearing 17 second flywheel 18 multi-stage viscous viscous coupling 19 torsion spring 30 drive side plate 32 driven side plate 33 floating plate 322 slit 332 slit

Claims (1)

[Claims] 1. A first flywheel that is integrally connected to a crankshaft of an internal combustion engine to rotate, and a second flywheel that is pivotally supported by a boss portion of the first flywheel via a bearing and has a clutch joint surface. A multi-stage viscous viscous coupling that is provided between the first flywheel and the second flywheel and that transmits torque between them based on the viscosity of the oil; and a relative position between the first flywheel and the second flywheel. A multi-stage viscous coupling between a driving plate on the first flywheel side and a driven plate on the second flywheel side of the multistage viscous coupling. A floating plate is interposed, and the floating plate and the one flywheel side plate are mutually Multistage viscous viscous damper, wherein the opposable damping force slit for adjustment is formed respectively.