JPH0235077Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an engine torque fluctuation absorbing device.

[Prior Art] In engines of automobiles, ships, etc., a torque fluctuation absorbing device is provided in a power transmission device in order to absorb torque fluctuations.

Conventional torque fluctuation absorbing devices of this type include, for example, Japanese Patent Publication No. 56-43176 and Japanese Patent Application Laid-open No. 55-1989.
There is a device as shown in Publication No. 20930.

The conventional device will be explained in advance using FIG. 7. The torque fluctuation absorbing device shown in FIG. 7 includes a drive plate 10 connected to the crankshaft of an engine and rotating.
1 and a flywheel 102 that stands concentrically in parallel with the drive plate 101 and rotates while being connected to a driven member so as to be rotatable relative to the drive plate 101. It consists of a device in which a spring mechanism 103 and a torque limit mechanism 104 are disposed between the drive plate 101, the spring mechanism 103, and the torque limit mechanism 104. torque fluctuations are absorbed.

[The problem that the idea aims to solve]

However, in the above-mentioned conventional torque fluctuation absorbing device, the drive plate 101 is made by cutting the entire casting, but in the case of a cast structure, cavities are likely to occur and it is not possible to make the device thinner in the axial direction, which makes the device more compact. There was a problem that it was difficult.

In order to solve these problems, the present invention aims to reduce the axial thickness of the drive plate by changing the drive plate structure from the conventional one, and to achieve this without reducing the strength. It is something.

[Means to solve the problem]

In order to achieve the above object, the torque fluctuation absorbing device of the present invention includes a drive plate connected to a drive shaft and a flywheel disposed coaxially with the drive plate and supported on the drive plate so as to be relatively rotatable. A spring mechanism, a torque limit mechanism, and a hysteresis mechanism are interposed between the drive plate and the flywheel. The drive plate is composed of an outer drive plate body, a side plate fixed to the axial side surface of the outer drive plate body on the drive shaft side, and an inner drive plate body fixed to the drive shaft side side plate. has been done.
The side plate on the drive shaft side is made of a steel plate.
Furthermore, the load supporting points on both sides of the side plate on the drive shaft side in the axial direction are arranged at different positions in the radial direction.

[Effect]

In the torque fluctuation absorber constructed in this way, the strength and reliability of the side plate is improved by constructing the side plate from a steel plate, so the side plate can be made thinner, and the axial dimension of the torque fluctuation absorber can be reduced. It can be done. In addition, bending stress is generated on the side plate on the drive shaft side when the torque fluctuation absorber is twisted relative to the drive shaft, but since the load supporting points on both sides of the side plate are different in the radial direction, The sum of the stress amplitude values of the generated bending stress is small, and sufficient strength is ensured despite the reduction in the axial dimension.

〔Example〕

Hereinafter, preferred embodiments of the torque fluctuation absorbing device of the present invention will be described with reference to the drawings.

In FIGS. 1 and 5, a drive plate 2 is connected by bolts to an engine crankshaft 1 serving as a drive shaft and rotates integrally therewith.
The drive plate 2 is a ring-shaped outer peripheral drive plate main body 2a forming an axial center portion.
, side plates 2c and 2d made of steel plates from both sides in the axial direction.
These are sandwiched from both sides by rivets 3 to connect them together, and the inner peripheral side drive plate main body 2b is integrally connected to the drive shaft side steel plate 2c with screws 4. The drive plate main body 2b on the inner peripheral side has a protrusion 2b' projecting radially outward on the outer periphery of the side plate 2c on the drive shaft side, and the outer periphery of the drive plate main body 2b and the side surface of the protrusion 2b' are formed. Together, they form a bearing guide into which the bearing 7 is fitted. The protrusion 2b' receives the thrust force from the bearing 7 and prevents the thrust force from being applied to the side plate 2c. By making the side plate 2c a steel plate and having the protrusions 2b' take charge of the thrust force, the side plate 2c can be made of a thin steel plate. In addition, the opening edge of the side plate 2c is bent outward in the axial direction at a portion that accommodates the spring mechanism 12, which will be described later, but this can be easily formed by press forming because press forming has become possible by using a steel plate. . The side plate 2c of the drive plate 2 is sandwiched between the crankshaft 1 and the inner drive plate main body 2b which functions as a bearing guide, and the outer diameter end corners 23 and 24 of the members 1 and 2b are connected to the torque fluctuation absorbing device. However, the load supports 23 and 24 are shifted in position from each other in the radial direction, so that the corner 24 of the inner drive plate main body 2b is located closer to the outer circumference than the corner 23 of the crankshaft 1. are doing.

Among the side plates constituting a part of the drive plate 2, the side plate 2d on the side of the flywheel 6 is bent so as to cover the outer periphery of the flywheel 6 so that the outer periphery thereof has a substantially L-shaped cross section to form a cylindrical protrusion 2d'. , this cylindrical protrusion 2d' covers the outer peripheral opening of a gap 11 existing between the drive plate 2 and the flywheel 6 and extending linearly in the radial direction. A starting ring gear 5 is attached to the outer periphery of the drive plate main body 2a by press fitting, shrink fitting, or the like.

The drive plate 2 is placed parallel to the drive plate 2 and coaxially with the drive plate 2.
A flywheel 6 is arranged to be rotatable relative to the drive plate 2 through a bearing 7.
is rotatably supported. 8 is a pin for positioning a clutch (not shown), and 9 is a screw hole for attaching a clutch cover (not shown). The flywheel 6 is divided into two parts, a flywheel main body 6a and a driven plate 6b, in order to accommodate a torque limit mechanism 15, which will be described later.The flywheel main body 6a and the driven plate 6b are integrally connected to each other by bolts 10. combined.

A spring mechanism 12 is provided between the drive plate 2 and the flywheel 6. The spring mechanism 12 includes a coil spring 13 and springs 13 provided at both ends of the coil spring 13.
It consists of a spring seat 14 with a cushion 14a that can be deformed with a stronger spring constant. The spring seats 14 provided at both ends of the coil spring 13 have the same shape. The spring mechanism 12 is housed in a window or notch provided in the side plates 2c and 2d of the drive plate 2,
One spring seat 14 contacts the edges of the windows and notches of the side plates 2c and 2d of the drive plate 2,
The other spring seat 14 extends radially outward from a driven plate 16, which will be described later.
6b to transmit torque. And when no torque is applied,
A gap exists between one spring seat 14 and the arm 16b with which the spring seat 14 comes into contact, producing play characteristic A shown in FIG. However, characteristic A depicts hysteresis due to the presence of a hysteresis mechanism 18, which will be described later. Further, in FIG. 5, characteristic B is caused by the deflection of the spring 13, and characteristic C is caused by the deformation of the cushion 14a of the spring seat 14 when the spring 13 is compressed and the spring seats 14 come into contact with each other.

The torque limit mechanism 15 is connected to the flywheel 6
As shown in FIG. 3, it is interposed between a pair of driven disks 16, and the pair of driven disks 16 are connected to a flywheel main body 6a,
It is composed of a cone spring 17 that presses against the driven plate 6b, and a lining 16a made of a friction material provided on the surface of the driven disk 16 that contacts the flywheel body 6a and the driven plate 6b. The torque limit mechanism 15 causes slippage due to the torque exceeding the sliding friction force between the lining 16a, the flywheel body 6a, and the driven plate 6b. The cone spring 17 determines the pressing force of the driven disc 16 against the flywheel body 6a and the driven plate 6b, but when the torque is within the torque corresponding to the frictional force determined by this pressing force, the driven disc 16 and the fly The wheel 6 rotates as a unit, and when the torque exceeds the torque corresponding to the frictional force, the driven disk 16 and the flywheel 6 cause relative slippage, cutting off the transmission of torque exceeding the frictional force. Characteristic D in FIG. 5 indicates a property in which the transmission of torque exceeding the torque corresponding to the frictional force is cut off.

The hysteresis mechanism 18 is connected to the drive plate 2
and the flywheel 6. FIG. 4 shows the hysteresis mechanism 18. As shown in the figure, the hysteresis mechanism 18 includes a plate 1 to which a lining member 19a made of a friction material is attached.
9 and attach the bent portion to the drive plate 2.
The plate 19 is fixed to the drive plate 2 in the circumferential direction by engaging with the hole 22 made in the side plate 2c, and the disc spring 20 and the plate 21 are interposed between the plate 19 and the side plate 2c to line the plate 19. It consists of a member 19a pressed against the flywheel 6. The sliding friction between the lining member 19a and the flywheel 6 provides hysteresis characteristics as shown in FIG.

Next, the operation in the above embodiment will be explained. The rotational torque of the crankshaft 1 of the engine is transmitted to a drive plate 2 that rotates integrally with the crankshaft 1, and is transmitted to the flywheel 6 via a spring mechanism 12, a torque limit mechanism 15, and a hysteresis mechanism 18. At this time, torque fluctuations of the crankshaft 1 and engine speed fluctuations are absorbed by a vibration system consisting of the spring of the spring mechanism 12, the damping of the hysteresis mechanism 18, and the inertial bodies of the drive plate 2 and flywheel 6.

In order to effectively absorb vibrations in the rotation speed range above the idle rotation speed, it is necessary to have soft spring characteristics when the relative rotational displacement (torsion angle) between the drive plate 2 and the flywheel 6 is small. . Further, in order to make the spring mechanism 12 compact, it is necessary to have a stiff spring characteristic when the relative rotational displacement is large. Furthermore, in order to protect the powertrain in the event of excessive torque being applied, it is necessary to limit the torque transmitted to the clutch. The torque fluctuation absorbing device of the present invention has the characteristics shown in FIG. 5 and satisfies the above requirements. That is, when the torque is low, the play between the spring seat 14 and the arm 16b of the driven disc 16 and the hysteresis caused by the hysteresis mechanism 15 work effectively to obtain characteristic A, and thereby, in the small torsion angle range. Soft spring characteristics can be obtained. When the spring seat 14 and the driven disk 16 come into contact, the spring 13 is deflected by a greater torque to obtain the characteristic B, and as the torque becomes even larger, the deflection of the spring 13 increases, and when the spring seats 14 come into contact with each other, the spring 13 becomes more deflected. Cushion 1 of spring seat 14 with torque
4a is bent to obtain characteristic C. This provides stiff spring characteristics in the large torsion angle range. When the torque further increases and becomes excessive, the torque limit mechanism 15 slips, and the torque exceeding the torque corresponding to the set frictional force is cut off, obtaining characteristic D and protecting the power train. In this way, torque fluctuations are effectively absorbed and transmitted to the powertrain.

In order to install the torque fluctuation absorbing device as described above in a position with limited space and to obtain sufficient strength and durability, the side plate 2c of the drive plate 2 is manufactured separately from the drive plate bodies 2a and 2b. It is made of steel plate. Steel plates are more reliable in terms of strength than cast metals, so they can be made thinner, and this thinner plate allows the shaft of the drive plate to be made thinner than when the entire drive plate is formed by cutting the castings. The directional dimension is reduced.

Further, the opening edge 2c' of the spring mechanism 12 housing portion of the side plate 2c is bent outward in the axial direction by pressing or the like, and thereby the drive plate 2
Even if the thickness of the drive plate 2 is small, the spring 13 can be accommodated, and the thickness of the drive plate 2 can be reduced.
The bending of the end portion 2c' is possible because the side plate 2c is made of a steel plate. By making the side plate 2c thinner by using a steel plate, when the torque fluctuation absorbing device is twisted relative to the crankshaft 1, a load is applied from the load supports 23 and 24, and a varying load of bending stress is applied to the side plate 2c. When the load supports 23 and 24 are aligned in the radial direction, the amplitude of the fluctuating stress generated on the side plate 2c is equal to the bending stress δa applied to the portion corresponding to the load supports 23 and 24, as shown in FIG. , δb. However, in the device of the present invention, the load supports 23 and 24 are shifted, so the amplitude of the fluctuating stress generated on the side plate 2c is the sum of the load supports 23 and 24, as shown in FIG. The bending stress δa applied to the load fulcrum is the sum of the bending stress δb applied to the part corresponding to the other load fulcrum, and the bending stress δb′ applied to the part corresponding to the one load fulcrum, and δb′<
δb, so the amplitude of the fluctuating stress is small. Therefore, the strength against fluctuating loads and repeated loads is increased, and structural reliability is improved.

[Effect of idea]

According to the torque fluctuation absorbing device of the present invention, since the side plate 2c of the drive plate 2 is made of a steel plate, the axial dimension of the torque fluctuation absorbing device can be reduced by improving the strength of the steel plate. In addition, since the load supporting points on both sides of the side plate 2c are shifted in the radial direction, the sum of the fluctuating bending stress generated on the side plate becomes small, and even if the side plate is made thinner, sufficient strength can be ensured.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a torque fluctuation absorbing device according to an embodiment of the present invention, and is a sectional view taken along the - line in FIG. 2, and FIG. 2 shows an internal structure of the device shown in FIG. FIG. 3 is a partial sectional view of the torque limit mechanism section of the device section of FIG. 1, and FIG.
The figure is a partial cross-sectional view of the hysteresis mechanism part of the device shown in FIG. 1, FIG. 5 is a torque transmission characteristic diagram of the device shown in FIG. 1, and FIG. 6 is a stress variation diagram applied to the side plate of the device shown in FIG. FIG. 7 is a sectional view of a conventional torque fluctuation absorbing device. 1...Drive shaft (crankshaft), 2...Drive plate, 2b'...Protrusion, 2c, 2d...Side plate,
2c'...Opening edge, 2d'...Cylindrical projection, 6...
Flywheel, 6a...Flywheel body,
6b... Driven plate, 12... Spring mechanism,
13... Spring, 15... Torque limit mechanism, 16... Driven disk, 18... Hysteresis mechanism, 23, 24... Load fulcrum.

Claims (1)

[Scope of utility model registration request] A drive plate connected to a drive shaft and a flywheel disposed coaxially with the drive plate and supported on the drive plate so as to be relatively rotatable constitute an inertial body, and an inertial body is formed between the drive plate and the flywheel. A spring mechanism, a torque limit mechanism, and a hysteresis mechanism are interposed in the
In the torque fluctuation absorbing device that transmits the rotation of the drive shaft to the flywheel via the drive plate, a spring mechanism, a torque limit mechanism, and a hysteresis mechanism, the drive plate is connected to an outer drive plate main body, an outer drive plate main body, It is composed of a side plate fixed to the axial side surface on the drive shaft side, and an inner peripheral side drive plate main body fixed to the side plate on the drive shaft side, the side plate on the drive shaft side is made of a steel plate, and the side plate on the drive shaft side is made of a steel plate. A torque fluctuation absorbing device characterized in that the load supporting points on both axial sides of the side plate are arranged at different positions in the radial direction.