JP3206977B2 - Multi-stage viscous damper - Google Patents

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 viscous damper which is mounted on a flywheel rotating in an internal combustion engine body and reduces engine vibration caused by torque fluctuations.

[0002]

2. Description of the Related Art During operation, an internal combustion engine performs an explosion stroke at a constant crank angle for each cylinder. Therefore,
In the internal combustion engine main body, vertical vibration, rotational vibration around the rotation center line of the crankshaft, and torsional vibration of the crankshaft itself are generated. 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, and causes noise of the internal combustion engine main body.
Further, the rotational vibration applied to the internal combustion engine main body is accompanied by rotational fluctuations generated in the explosion stroke of each of the opposed cylinders dispersed in the longitudinal direction of the crankshaft, and these are rolled to the main body side of the internal combustion engine through bearings. Joined as a moment,
This is a factor in the noise of the internal combustion engine body. 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 is a factor of noise of the main body of the internal combustion engine.

[0003] Among these noise factors, the vertical vibration applied to the internal combustion engine body is reduced by using a silent shaft that cancels the vertical vibration by the rotation of the unbalanced mass. It is known that this can be reduced by a rolling moment elimination device having a sub 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 also 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 wheels via the clutch, resonance occurs at a resonance point indicated by f1 in FIG. 10, for example. Engine and vehicle body noise. Therefore, if the resonance point is placed before the idle region, resonance in the normal rotation region 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 characteristics as shown by. Therefore, it is conceivable to mount a damper between the first mass and the second mass in order to reduce the body noise by reducing the amplitude in the low rotation range. In this case, as shown by the broken line b, the amplitude at the resonance point f2 in the low rotation range is relatively reduced, but in this case, the amplitude in the high rotation range becomes higher than that of the comparator. Therefore, the damping rate of the damper is not made unity, but the damping rate in the low frequency (low rotation speed) region is set relatively large, and the damping ratio in the high frequency (high rotation speed) region is set relatively small. As a result, the chain line c in FIG.
It is desirable to obtain the characteristics as shown in FIG.

[0004] For example, a crankshaft torsional vibration damper as shown in FIGS.
A second mass 2 pivotally supported by the first mass 1 via the mass 1 and the bearing 3; a driven plate 4 disposed between the first and second masses; a driven plate 4 and a drive plate 5 on the first mass side And a torsion spring 7 provided between the driven plate 4 and the second mass.

In this case, when the torsional vibration of the crankshaft is in a high frequency (high rotation speed) region, the slide stopper 8 slidably supported by the drive plate 5 and the projection 9 of the driven plate 4 are filled. The oil moves relative to the flow resistance of the oil within the AC operation angle θ1 to perform the damper operation. On the other hand, when the torsional vibration is in a low frequency (low rotational speed) 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 pressed against the flow resistance of the further filled oil. 1
The relative movement is performed within the DC operation angle θ2 until the damper operation is performed. When the amplitude is particularly large, the drive plate 5, the slide stopper 8, and the driven plate 4 are integrated, and these deform the torsion spring 7 elastically, relatively change with the second mass 2, and absorb the impact. Operate.

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

[0007]

However, in the crankshaft torsional vibration damper as shown in FIGS. 8 and 9, the damping rate is set based on the flow resistance of the oil. However, there is a problem that a high accuracy is required for setting the amount of restriction of the flow path, a large number of parts are required, and the manufacturing cost is relatively high. It is an object of the present invention to provide proper rotational vibration over a wide torque range of the engine.
It is an object of the present invention to provide a multi-stage viscous viscous damper capable of reducing movement and reducing engine and vehicle body noise .

[0008]

In order to achieve the above-mentioned object, the present invention provides a first flywheel which is integrally connected to a crankshaft of an internal combustion engine and rotates, and a bearing is provided on a boss of the first flywheel. a second flywheel clutch bonding surface is pivoted has been made form through, is equipped between the first flywheel and the second flywheel, multistage viscous viscous performed based torque transmission therebetween on the viscosity of the oil and coupling the first flywheel and the second
A multi-stage viscous viscous damper having a torsion spring disposed between the flywheel and absorbing a relative rotational displacement therebetween and transmitting an average torque.
The multi-stage viscous viscous coupling is connected to the first
A drive side plate connected to the rye wheel side;
2 The driven plate connected to the flywheel side
Between the drive side plate and the driven side plate.
And a floating plate,
And one of the driven side plates and the flow
Damping force adjustment that can face each other
Characterized that you have a slit in use.

[0009]

In this case, slits for adjusting the damping force are formed in the floating plate and one of the flywheel side plates, and the opposing portions of the portions other than the slits of the two plates that can transmit the viscous torque are kept relatively small. When the ratio increases, a low damping rate can be achieved, and conversely, when the ratio at which the degree of opposition between the portions capable of transmitting the viscous torque in the portions other than the slits of both plates is relatively large is increased, the viscous torque increases, High attenuation rate can be achieved. For this reason, when the flywheel receives a small amplitude in a high rotation speed (high frequency) range, the flywheel easily slips, that is, a low damping rate in which portions other than the slits of the two plates capable of transmitting the viscous torque are kept relatively small. On the other hand, in a state where a large amplitude is received in a low rotation speed (low frequency) range, a slip is hard to occur, that is, a high damping rate in which portions other than the slits of the two plates capable of transmitting the viscous torque are relatively large is maintained. Can be achieved.

[0010]

FIG. 1 shows a multi-stage viscous viscous damper according to the present invention. This multi-stage viscous viscous damper is connected to a crankshaft 11 and a clutch 12 of an engine (not shown).
And is mounted in a two-piece flywheel 13 integrally connected to the crankshaft 11, and serves as a crankshaft torsional vibration damper.
It is configured to reduce the torsional vibration of.

The multi-stage viscous viscous damper includes a first flywheel 14 integrally connected to an end of the crankshaft 11 and a second flywheel pivotally supported by a boss 15 of the first flywheel 14 via a bearing 16. Wheel 17
And the first flywheel 14 and the second flywheel 17
A multi-stage viscous viscous coupling 18 provided between the
A torsion spring 19 is provided between the first flywheel 14 and the second flywheel 17. Moreover, the second flywheel 17 integrally has a clutch cover 20 attached to the side opposite to the clutch 12 and supports a pressure plate 21 via a diaphragm spring 22 in the clutch cover. The diaphragm spring 22 also functions as a release lever that pivots the pivot ring 24 at a fulcrum, and presses the pressure plate 21 against the clutch plate 23 to disengage it. The clutch plate 23 that rotates integrally with the output shaft 25 is the second flywheel 1
7, so that the torque transmission can be performed intermittently by contacting or separating from the clutch connecting surface 26 of the clutch.

Outer peripheral teeth 27 meshing with a starter (not shown) are formed on the outer peripheral portion of the first flywheel 14, and torsion springs 19 are respectively supported at predetermined intervals on the inner circumference thereof. One end (the front side in FIG. 1) of the torsion spring 19 is the first
The other end is supported by a spring receiver (not shown) on the flywheel 14 side, and the other end is supported by a spring receiver 17 on the second flywheel 17 side.
1 and is supported.

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

On the outer peripheral wall of the driving rotator 28 and the inner peripheral wall of the driven rotator 31, long splines 34 and 35 are formed in the longitudinal direction Y of the crankshaft, in which a driving plate 30 and a driven plate 32 are formed. Each is configured to mesh. Moreover, the driven rotary member 31 is formed in a hollow circular-shaped having an open inner peripheral side, the opening of the annular hollow body is covered with an annular plate portion of the drive rotor 28 to form an annular chamber B. Reference numerals 36 and 37 denote seal rings. Silicon oil filled between the driving side plate 30, the driven side plate 32, and the floating plate 33 inside the annular chamber B fills the driven rotating body 31 and the driving rotating body 28.
This prevents the annular plate portion from slipping off the sliding contact surface f.

As shown in FIG. 3 (c), the drive side plate 30 has inner peripheral teeth 301 meshed with the splines 34 on the inner peripheral edge thereof, and the outer peripheral edge does not reach the tip of the spline 35. The outer diameter is formed. As shown in FIG. 3B, the floating plate 33 has a center 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. At regular intervals in the circumferential direction, slits 332 having a width C1 relatively wider than the face width of the inner peripheral teeth 301 are formed. As shown in FIG. 3A, the driven side plate 3
2 is an outer peripheral tooth 32 which meshes with the spline 35 on the outer peripheral edge thereof.
1 is formed, and a center hole 323 which is loosely fitted in the spline 34 is formed. A slit C2 having a width C2 which is relatively equal to the width of the inner peripheral teeth 301 at its inner peripheral edge at equal intervals in the circumferential direction. 322 are formed. Each plate 30,
32 and 33 are formed in a thin disk shape having a uniform thickness.
As shown in the figure, the driven side plate 32 and the driving side plate 3
0 are stacked with the floating plate 33 interposed therebetween.

A pair of large and small rings (not shown) made of a very thin steel material for clearance adjustment are interposed between the plates, one pair on the inner peripheral side and the other on the outer peripheral side. The gap between the plates is kept constant.

The operation of the above-described multi-stage viscous viscous damper 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 variations of relative rotation angle (indicating the average of the amplitude at that time in Fig. 5 as H _0/2)
Deeds, moreover, torsion spring 19 is first flywheel 14 side row torque transmitted through the spring bearing and the second flywheel 17 side of the spring receiving 171 not shown <br/>. Here, when the engine is stopped, the multi-stage viscous
How about the floating plate 33 of the coupling 18
Several times after starting the engine.
The floating plate 33 plays on the drive side
Between the plate 30 and the driven plate 32 with the least resistance.
In other words, as shown in FIG.
Rate plate portion 333 (parts other than slit 332)
Position) and the plate portion 324 of the driven side plate 32 (slip)
Where the viscous torque can be transmitted at the part other than the
, That is, the size of the polymerization zone is kept relatively small.
The state converges to a leaning state (for example, W1 in FIG. 6A). So
Engine vibration from the position once
The operation for reducing the amplitude is started. Here, an engine not shown
When the speed is in the high rotation speed (high frequency) range, multi-stage viscous
The coupling 18 has a relatively small amplitude h ₀ (see FIG. 5).
Vibrating), and keep the slippery condition. in this case,
Plate portion 32 of both plates capable of transmitting viscous torque
Increase / decrease displacement of the size of the overlap zone, which is the degree of opposition of 4,333
Is repeated in a relatively small state, ie, as shown in FIG.
The overlap area is increased or decreased based on the state where the overlap area W1 shown is maintained.
And a low attenuation rate can be achieved. Thus, high rotation speed (high
In the (wave number) range, high-frequency torsional vibration can be suppressed with a relatively low damping rate, and engine and vehicle body vibration can be reduced.

On the other hand, when the engine ( not shown ) is in a low rotation speed (low frequency) range equal to or lower than the idle rotation , the relative rotation angles of the first flywheel 14 and the second flywheel 17 are set.
Changes to a state where a relatively large amplitude is received, and the rate at which the fluctuation of the rotation angle of the low frequency component (the outline of the waveform at that time is shown by a two-dot chain line in FIG. 5 and the amplitude is shown as H1) is increased. Therefore, multi-stage viscosity viscous coupling 18 and the drive-side plate 30 and the driven-side plate 32 is repeated a large variation. In this case, the weight shown in FIG.
The plates increases its amplitude state for holding the engagement region W1 as a reference, as shown in FIG. 6 (b), slip hesitation state, i.e. the plate part 3 of the floating plate 33
33 overlaps the plate portion 324 of the driven side plate 32.
And the overlapping area W2 capable of transmitting the viscous torque is relatively large.
A maintained high attenuation rate can be achieved. For this reason, in the low frequency range below the idle speed, the amplitude of the torsional vibration can be suppressed in a state of a relatively high damping rate, whereby the engine and vehicle body vibration in the low speed range can be reduced.

In the above, the driven side plate 3
2 and the floating plate 33 with the slit 322,
332 is formed, the ratio of the slits 322 and 332 facing each other is changed, that is, the overlapping regions W1 and W2 capable of transmitting the viscous torque are changed between the low rotation region and the high rotation region, and the high damping rate is reduced in the low rotation region. Had a low damping rate in the high rotation range. Instead, the driven side plate 32 was formed as a single disk without slits, and the drive side plate 30 and the floating plate 33 were formed with slits. In this case as well, a high damping rate can be obtained in the low rotation range and a low damping rate can be obtained in the high rotation range.
The same operation and effect as those of the device 1 can be obtained.

In the above description, there was no restriction on the relative rotation fluctuation amount between the floating plate 33 and the driven side plate 32. However, as shown in FIG. 7, a stopper 40 was formed on the driven side plate 32a, The stopper may be formed so as to regulate the relative variation amount s of the floating plate 33. In this case, when the stopper 40 is locked to the floating plate 33 and slides integrally with the overlapping region W3 at the low damping rate, the overlapping region at the high damping ratio becomes large as W4. The damping operation during operation in the range is reliably performed, and the response to the high damping rate is improved.

[0022]

As described above, according to the present invention, a slit for damping force adjustment is formed in the floating plate and one of the flywheel-side plates, and the portions of the two plates other than the slit are capable of transmitting viscous torque. When the ratio of maintaining the degree relatively small increases, a low damping rate can be achieved, and conversely, the ratio of the parts other than the slits of the two plates that can transmit the viscous torque in the parts other than the slits increases, which increases the ratio This increases the viscous torque and achieves a high damping rate. For this reason, when the flywheel receives a small amplitude in a high rotation speed (high frequency) range, it can easily slip, that is, a low damping rate can be achieved in which the portions of both plates capable of transmitting the viscous torque are kept relatively small, slip state to undergo large amplitude in reverse at a low rotational speed (low-frequency) band and hesitation state, i.e. a viscous torque can be transmitted can in achieving high attenuation factor site of the plates is kept relatively large, immediately
That is, depending on the vibration amplitude in the rotation direction,
The relative rotational position of the flywheel side plate changes,
This allows the slit on the floating plate to
The degree of opposition of the slits on the flywheel side plate changes.
And the damping force is adjusted appropriately, so that the engine
To reduce vibration in the rotational direction appropriately over the
Engine and vehicle noise can be reduced.

[Brief description of the drawings]

FIG. 1 is a partial sectional view of a multi-stage viscous viscous damper as one embodiment of the present invention.

FIG. 2 is a cross-sectional view of the viscous damper of FIG.

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

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

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

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

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

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

FIG. 9 is a partial sectional side view of the crankshaft torsional vibration damper of FIG. 8;

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

[Explanation of symbols]

 Reference Signs List 11 crankshaft 14 first flywheel 15 boss 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)

(57) [Claims] 1. A a first flywheel which rotates integrally coupled to the crankshaft of an internal combustion engine, a second fly was made form the clutch bonding surface is pivotally supported via a bearing boss of the first flywheel and the wheel, the disposed between the first flywheel and the second flywheel, and a multi-stage viscosity viscous coupling performed based on the viscosity of the oil torque transmission therebetween, the first flywheel and the second the flywheel
It is disposed between, and a torsion spring for transmitting the average torque while absorbing the relative rotational displacement therebetween
In the multi-stage viscous viscous damper, the multi-stage viscous coupling includes a driving plate connected to the first flywheel side.
And a driven press connected to the second flywheel.
Between the drive side plate and the driven side plate.
And a floating plate disposed on one of the drive side plate and the driven side plate.
And the floating plate above
Multistage viscous viscous damper, wherein the formation of the slit for the damping force control possible and this.