JPH0674301A - Flywheel - Google Patents

Abstract

PURPOSE:To improve the durability of a flywheel which reduces the torque fluctuation of a rotary system in a high temperature by making a damper mass which performs pendulous movement function as a dynamic damper. CONSTITUTION:A subrotor 10 containing a damper mass 12 which performs pendulous movement in synchronism with the rotary fluctuation which occurs in a crank shaft 1 is provided separately from a main rotor 3 which transmits drive force between clutch disks 4. The axial rigidity of the middle part 10A of the subrotor 10 is made small by thinning the middle part 10A.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a flywheel, and more particularly, to a constant-order torque fluctuation of a rotary drive system provided with the flywheel.

[0002]

2. Description of the Related Art A driving force of an internal combustion engine such as a vehicle engine is obtained by converting a combustion force into a rotational force (torque) by a crank mechanism. ) Occurs, which causes vibration and noise. Specifically, in the case of a 4-cycle 4-cylinder engine, the secondary component of engine rotation, and in the case of a 6-cylinder, it is 3
The rotational fluctuation of the next component becomes a problem.

As a conventional technique for solving such a problem, Japanese Utility Model Laid-Open No. 1-115309 (first conventional example).
Alternatively, there are those described in the specification of Japanese Patent Application No. 3-274108 (second conventional example) previously proposed by the present applicant. That is, these conventional flywheels house a damper mass capable of pendulum motion in the flywheel body, and reduce the torque fluctuation of the internal combustion engine by the pendulum motion of the damper mass.

[0004]

However, in the above-mentioned prior art, since the centrifugal pendulum structure for reducing the torque fluctuation is integrally provided within the flywheel body, the torque fluctuation is reduced and the driving force is reduced. When applied to a rotating body that is exposed to high temperatures, such as a flywheel that also performs transmission (for example, a flywheel that constitutes a vehicle clutch), its durability becomes a problem.

That is, since the Young's modulus of the material generally decreases at high temperatures, a space for accommodating the damper mass is formed in order to support the centrifugal force acting on the damper mass and to perform an appropriate pendulum motion at high rotation and high temperature. It is necessary to increase the rigidity of the flywheel by increasing the wall thickness etc. or using a material with high rigidity at high temperature,
If the wall thickness or the like is increased, the weight becomes heavier, so that the inertial performance rate increases and the responsiveness deteriorates. If a material having high rigidity is used, the cost also increases. Further, in the structure in which the damper mass is supported by the bearing to perform the pendulum motion as in the first conventional example, it is necessary to take measures to prevent seizure of the bearing.

Further, in the flywheel integrally provided with the centrifugal pendulum structure, in order to prevent the performance of the centrifugal pendulum from being deteriorated due to the surface runout of the flywheel, a highly rigid material is used or the thickness of the flywheel is increased. Therefore, it is necessary to increase the rigidity of the flywheel and eliminate the bending resonance of the crankshaft beyond the normal rotational speed. However, similar to the above problems, there are problems in cost and responsiveness. Then, the method of removing the bending resonance of the crankshaft beyond the normal rotation speed can solve one rotation order, but the bending resonance of the crankshaft occurs for other rotation orders, so the surface deflection of the flywheel occurs. There is an unsolved problem that the deterioration of the performance of the centrifugal pendulum due to the above is not sufficiently solved.

The present invention has been made by paying attention to the unsolved problems of the conventional techniques as described above.
The centrifugal pendulum structure aims to improve the durability of the flywheel at high temperatures, which reduces torque fluctuations.

[0008]

In order to achieve the above object, the invention according to claim 1 uses a sub-rotor for reducing torque fluctuations, which accommodates a damper mass that makes a pendulum motion, and a main rotation for transmitting driving force. It was provided separately from the body. In the invention according to claim 2, in the invention according to claim 1, the rigidity in the axial direction of the portion of the sub-rotor radially inside the damper mass housing position is reduced.

According to a third aspect of the present invention, in the above-mentioned first or second aspect of the present invention, the sub-rotating body is coupled to the main rotating body via the radially inner edge portion. Further, in the invention according to claim 4, in the invention according to any one of claims 1 to 3, the damper mass is located radially outside of the outer diameter of the main rotating body.

[0010]

According to the first aspect of the invention, the main rotating body for transmitting the driving force and the auxiliary rotating body for reducing the torque fluctuation, which are exposed to a high temperature due to frictional heat in the clutch, are separate bodies. , The heat of the main rotating body does not directly act on the damper mass or the wall surface forming the space for accommodating the same, and therefore the wall thickness of the wall surface forming the damper mass accommodating space of the sub rotating body should be adjusted to prevent heat. No need to increase.

Since the torque fluctuation of the rotary drive system is reduced mainly by the pendulum motion of the damper mass housed in the sub rotary body, the main rotary body needs only to mainly transfer the driving force. There is almost no need to increase the mass of the rotating body to reduce the torque fluctuation. For this reason, the flywheel as a whole can be made lighter than the structure in which the damper mass is housed in the main rotating body for transmitting the driving force, and the responsiveness is also improved.

Further, in the structure according to the second aspect of the present invention, when the radial inner portion of the sub-rotor has a small axial rigidity, the sub-rotor functions as a so-called flexible flywheel. The bending resonance of the rotary shaft to which the sub-rotor is attached can be easily removed below the normal rotational speed, and a smooth pendulum motion of the damper mass is secured.

According to the third aspect of the present invention, since the sub-rotating body is connected to the main rotating body, even if the sub-rotating body itself is separate from the main rotating body, the sub-rotating body can be easily mounted. The workability and the like are not particularly deteriorated, and since the sub-rotating body is coupled to the main rotating body via the edge portion on the radially inner side, the contact area between the rotating bodies is small and the heat transfer coefficient is low. Further, according to the invention of claim 4, since the damper mass housed in the sub-rotor is in a position where it is difficult to receive the radiant heat from the main rotor, the influence of the heat generated in the main rotor on the damper mass is exerted. It gets smaller.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 are views showing a first embodiment of the present invention, in which the flywheel according to the present invention is applied to a driving force transmitting portion of a vehicle. First, the structure will be described. As shown in FIG. 1, a crankshaft 1 of a vehicle engine and an input shaft 2 of a manual transmission are coaxially arranged, and the crankshaft 1 and the input shaft 2 are arranged between the crankshaft 1 and the input shaft 2. Then, the driving force is intermittently transmitted through the frictional force between the main rotor 3 coaxially fixed to the end of the crankshaft 1 and the clutch disc 4 coaxially fixed to the end of the input shaft 2. It is possible. The connecting / disconnecting mechanism between the main rotating body 3 and the clutch disc 4 is similar to that of the conventional vehicle clutch.

The main rotating body 3 has a central portion 3A and a peripheral portion 3B.
By making the space a tapered portion 3C having a smaller diameter on the central portion 3A side, the central portion 3A is formed in a disc shape recessed toward the vehicle engine side than the peripheral edge portion 3B. The main rotating body 3
A clutch cover 5 is fixed to the surface of the peripheral edge portion 3B facing the clutch disc 4 side so as to cover the clutch disc 4.

Further, on the left side (engine side) in FIG. 1 of the fixed position of the main shaft 3 of the crankshaft 1, a sub rotary member 10 for reducing torque fluctuation is fixed coaxially with the crankshaft 1. The rotary body 3 and the sub-rotary body 10 constitute a flywheel 20. The sub-rotational body 10 has a central portion 10A, which has a relatively small axial rigidity due to being formed relatively thin, a peripheral portion 10B which forms a plurality of rolling chambers 11, and an opening of the rolling chamber 11. Cover 1 that seals the side
0C, as shown in FIG. 2 which is a plan view of the sub-rotating body 10 with the cover 10C removed.
A plurality of (12 in this embodiment) rolling chambers 11, ..., 11 having the same shape are formed in the peripheral portion 10B at equal intervals in the circumferential direction.

Each rolling chamber 11 is composed of an arcuate recess which is recessed substantially parallel to the sub-rotating body 10. Inside each rolling chamber 11, centrifugal force is generated when the sub-rotating body 10 rotates. A damper mass 12 made of a thick disk that accommodates a pendulum motion while rolling on the radially inner surface of the rolling chamber 11 is accommodated. The dimensions of the rolling chamber 11 in the radial direction and the thickness direction are preferably the smallest in the range in which the damper mass 12 can roll.

The inner surface of each rolling chamber 11 is formed so that the trajectory of the pendulum motion of the damper mass 12 satisfies the theory of the centrifugal pendulum. Specifically, when the mass of the damper mass 12 is m _d , the inertia ratio of the damper mass 12 is I _d , the radius of the damper mass 12 is r _d , and the torque fluctuation order of the crankshaft 1 is n, the rotation of the sub-rotating body 10 the distance R to the fulcrum of the pendulum motion of the damper mass 12 from the center, the ratio R / L of the distance L from the fulcrum of the pendulum motion of the damper mass 12 to the center of gravity of the damper mass ^{12, R / L = n 2} {1 + I d / (M _d · r _d ² )} is set. Since the present embodiment has a plurality of damper masses 12, both the mass m _d and the inertial performance rate I _d are total values of the plurality of damper masses 12.

The main rotary body 3 and the sub rotary body 10 are
The holes 3a and 10a formed in the central portions of the crankshaft 1 are fitted into the convex portions 1A formed on the end surface of the crankshaft 1, and the crankshaft is cranked through the bolt holes 3b and 10b from the surface of the central portion 3A facing the clutch disc 4 side. Large diameter part 1B of shaft 1
The bolt 6 is fastened to the crankshaft 1 so as to be integrated in the rotational direction and the axial direction. A locating pin 7 for relative positioning between the main rotating body 3 and the sub-rotating body 10 is fitted at a position radially outside the bolt holes 3b, 10b of the central portions 3A, 10A.

In the peripheral portion 10B of the sub-rotating body 10, the sub-rotating body 1 is appropriately selected by appropriately selecting the radial dimension of the central portion 10A and the inclination angle of the taper portion 3C of the main rotating body 3.
It is arranged at a position where it does not come into contact with the main rotating body 3 even when 0 is bent in the axial direction. Next, the function and effect of this embodiment will be described.

The driving force generated by the engine is input to the manual transmission via the crankshaft 1, the main rotor 3, the clutch disc 4 and the input shaft 2. Then, in the crankshaft 1, if the engine is a 4-cylinder engine, a secondary torque fluctuation mainly occurs, and if it is a 6-cylinder engine, a tertiary torque fluctuation mainly occurs. It can be absorbed and reduced by the pendulum movement.

That is, when the torque fluctuation is transmitted to the crankshaft 1 and the torque fluctuation is transmitted to the sub-rotor 10,
As a result of selecting the ratio of the distances R and L so as to satisfy the theory of the centrifugal pendulum as described above, the damper mass 12 housed in the rolling chamber 11 makes a pendulum motion in synchronization with the torque fluctuation, which is a dynamic phenomenon. Since it acts as a damper, the torque fluctuation transmitted to the sub-rotational body 10 is surely reduced by the fluctuation of the center of gravity of the damper mass 12, and the torque fluctuation of the crankshaft 1 to which this is attached is significantly reduced. Therefore, the noise in the passenger compartment can be reduced.

Further, since the central portion 10A of the sub-rotating body 10 is formed relatively thin, the rigidity of this portion in the axial direction is reduced, so that the system formed by the crankshaft 1 and the sub-rotating body 10 is formed. The bending resonance of can be easily removed below the normal rotational speed, the muffled noise due to the bending resonance can be reduced, and the crankshaft 1 itself does not need to secure the conventional bending rigidity, and the crankshaft 1 itself is lightweight. Be promoted. Moreover, as a result of the sub-rotating body 10 functioning as a so-called flexible flywheel, there is an advantage that the surface runout of the peripheral edge portion 10B of the sub-rotating body 10 is prevented and the smooth rolling of the damper mass 12 is secured. Bending resonance of the system formed by the crankshaft 1 and the main rotating body 3 cannot reduce the rigidity of the main rotating body 3 that transmits the driving force. Need to be removed.

The transmission of the driving force between the crankshaft 1 and the input shaft 2 is performed via the frictional force between the main rotating body 3 and the clutch disc 4 as in the conventional vehicle. As described above, since the torque fluctuation of 1 is reduced in the sub-rotating body 10, the main rotating body 3 has only to mainly transfer the driving force, and therefore the mass of the main rotating body 3 absorbs the torque fluctuation. Therefore, it is not necessary to increase the thickness, and the thickness or the like may be selected from the viewpoint of the heat capacity when the temperature rises due to friction with the clutch disc 4.

Further, since the peripheral portion 10B of the sub-rotating body 10 in which the rolling chamber 11 is formed is not in contact with the main rotating body 3 which is heated to a high temperature by friction with the clutch disc 4, the rolling chamber 11 is Since heat countermeasures such as making the wall thickness particularly thick are unnecessary, and since the central portion 10A of the sub-rotating body 10 is formed thin, the weight increase due to providing the sub-rotating body 10 separately is not so great. Not many.

Rather, since the auxiliary rotary body 10 having the centrifugal pendulum structure is separately provided, the weight of the crankshaft 1, the main rotary body 3, etc. can be reduced as described above. Therefore, the centrifugal pendulum structure is used as the main rotary body. As compared with the structure of a conventional flywheel provided integrally in the inside of 3, the rotation system as a whole becomes lighter in weight, and the responsiveness can be improved. Further, when the dimensions of the rolling chamber 11 in the radial direction and the thickness direction are made as small as possible within the range in which the damper mass 12 can roll, there is an advantage that abnormal noise generated at the time of starting can be reduced.

FIGS. 3 and 4 are views showing a second embodiment of the present invention. In this embodiment as well, as in the first embodiment, the flywheel according to the present invention is applied to a driving force transmitting portion of a vehicle. It was done. The same members and parts as those in the configuration of the first embodiment are designated by the same reference numerals, and the duplicated description will be omitted. That is, this embodiment is similar to the first embodiment in that the auxiliary rotary body 10 is provided separately from the main rotary body 3, but the auxiliary rotary body 10 is not fixed directly to the crankshaft 1. Instead, the auxiliary rotary body 10 is fixed to the main rotary body 3 via the edge portion on the radial edge side, and the auxiliary rotary body 10 and the crankshaft 1 are not in contact with each other.

More specifically, as shown in FIG. 4, which is a plan view of the flywheel 20 as viewed from the left in FIG. 3, the inner diameter of the hole 10a of the sub-rotor 10 is set to the large diameter portion 1B of the crankshaft 1. And a bolt hole 10d is formed at four convex portions 10c in the circumferential direction of the hole portion 10a, and the bolt 13 is attached to the central portion 3A of the main rotating body 3 through the bolt hole 10d. By fastening, the sub-rotor 1
0 is connected to the main rotating body 3.

With this structure, the sub-rotating body 10 contacts only the main rotating body 3, and the contact area between the main rotating body 3 and the sub-rotating body 10 is also different from that of the first embodiment. Since it becomes extremely small (only in the region shown by the broken line in FIG. 4), most of the friction heat generated in the main rotor 3 flows to the crankshaft 1 side, and the temperature rise of the auxiliary rotor 10 is further reduced. be able to.

If the sub-rotating body 10 is connected to the main rotating body 3, there is an advantage that workability at the time of assembling is improved, and further, the thickness of the central portion 3A of the main rotating body 3 is increased. Since it becomes easier, it is also advantageous in increasing the rigidity of the main rotating body 3. Other functions and effects are similar to those of the first embodiment. FIG. 5 is a diagram showing a third embodiment of the present invention.

That is, in this embodiment, the basic structure is the same as that of the second embodiment, but the peripheral portion 10B for accommodating the damper mass of the sub-rotating body 10 is arranged in the radial direction from the outer diameter of the main rotating body 3. It is located outside. With such a configuration, the damper mass is located at a position where it is difficult to receive the radiant heat from the main rotating body 3, which is more advantageous in terms of heat countermeasures, and the damper mass is located closer to the rotation center of the sub rotating body 10. The further the position is, the greater the centrifugal force that occurs and the greater the effect of reducing torque fluctuations.

Furthermore, since the radial dimension of the central portion 10A of the sub-rotating body 10 also becomes large, the bending rigidity is substantially reduced without processing the plate thickness of this portion so much.
There is also an advantage that the function as a flexible flywheel can be easily exhibited. In other words, the central portion 10A is more easily affected by heat conduction from the main rotating body 3 than the peripheral portion 10B. Therefore, it is desirable that the plate thickness be thick in order to increase the rigidity at high temperatures. Although there is a problem that it becomes difficult to function, the configuration of this embodiment can satisfy both the requirement of increasing the rigidity at high temperature and the requirement of functioning as a flexible flywheel. .

Other functions and effects are similar to those of the first embodiment. In each of the above embodiments, the case where the flywheel according to the present invention is applied to the driving force transmission system of a vehicle having a manual transmission has been described.
The application target of the present invention is not limited to this. For example, even in a vehicle having an automatic transmission, the sub-rotating body 10 described in each of the above embodiments is provided separately from the pump for transmitting driving force which constitutes the torque converter included in the automatic transmission. In this case, it is possible to obtain the same effect as that of the above embodiment. Furthermore, the present invention can be applied to a rotating system other than the driving force transmission system of the vehicle.

[0034]

As described above, according to the present invention,
Since the sub-rotary body for reducing the torque fluctuation, which accommodates the damper mass that makes the pendulum motion, is provided separately from the main rotary body for transmitting the driving force, the durability at high temperature is improved. In particular, according to the second aspect of the present invention, since the sub-rotor functions as a flexible flywheel, bending resonance can be easily removed below the normal rotational speed, so that muffled sound can be reduced and the like. As a result of the surface wobbling of the rotating body being prevented, a smooth pendulum motion of the damper mass is secured.

According to the third aspect of the invention, the workability at the time of assembly can be improved, and the measure against heat of the sub-rotating body becomes more advantageous. Further, according to the invention of claim 4, since the damper mass is located at a position where it is hard to receive the radiant heat from the main rotating body, it is more advantageous in terms of heat countermeasures, and the damper mass can rotate the sub rotating body. The more distant from the center, the more centrifugal force is generated, the greater the effect of reducing torque fluctuations, and the more easily the function as a flexible flywheel is exerted.

[Brief description of drawings]

FIG. 1 is a side sectional view showing a configuration of a first embodiment.

FIG. 2 is a plan view of a sub rotary body.

FIG. 3 is a side sectional view showing a configuration of a second embodiment.

FIG. 4 is a plan view of a flywheel.

FIG. 5 is a schematic diagram showing a configuration of a third exemplary embodiment.

[Explanation of symbols]

 1 Crankshaft 2 Input Shaft 3 Main Rotating Body 3A Central Part 3B Peripheral Part 3C Tapered Part 4 Clutch Disc 10 Sub-Rotating Body 10A Central Part 10B Peripheral Part 10C Cover 11 Rolling Chamber 12 Damper Mass 20 Flywheel

Claims (4)

[Claims] 1. A flywheel comprising: a torque-reducing sub-rotor for accommodating a pendulum-moving damper mass, the sub-rotator being provided separately from a drive-power-transmitting main rotor. 2. The flywheel according to claim 1, wherein a radial inner side portion of the sub rotor having a damper mass accommodating position has reduced axial rigidity. 3. The flywheel according to claim 1, wherein the sub-rotating body is connected to the main rotating body via an edge portion on the radially inner side of the sub-rotating body. 4. The flywheel according to claim 1, wherein the damper mass is located radially outside of the outer diameter of the main rotating body.