JP5522099B2 - Vibration damping device - Google Patents

Description

  The present invention relates to an apparatus for attenuating torsional vibrations, and more particularly to a vibration damping apparatus having a configuration in which a rotating body that is rotatable relative to the rotating body is housed inside a rotating body that receives torque and rotates. It is about.

  Rotating bodies such as drive shafts and gears for transmitting the torque generated by the power source to the target location or member are caused by fluctuations in the input torque itself, fluctuations in the load, friction, etc. Inevitably vibrates. The frequency of the vibration changes according to the number of rotations, and a higher-order vibration higher than the secondary vibration is also generated. Therefore, the amplitude becomes large due to resonance, which may cause noise and durability deterioration. is there. For this reason, devices or mechanisms for preventing vibration as described above are widely used in various devices that transmit power by rotation. One example thereof is described in Patent Document 1.

  A centrifugal pendulum type vibration absorber described in Patent Document 1 includes a rolling chamber formed in a portion on the outer peripheral side of a rotating body such as a flywheel, and a ball or roller (roller) accommodated therein so as to roll freely. ) And other rolling elements, and when the rotating body rotates, the rolling element resonates with the torsional vibration and rolls inside the rolling chamber, and absorbs the torsional vibration by its dynamic vibration absorbing action. Is configured to do.

JP 7-280037 A

  In the centrifugal pendulum absorber described in Patent Document 1, a rolling element having an outer diameter smaller than the radius of the rolling chamber is accommodated in a circular rolling chamber. The rolling element has a cylindrical stopper projection formed at the center of both side surfaces thereof. An arcuate guide groove into which the stopper protrusion is fitted is formed on the side wall of the rolling chamber facing the side surface of the rolling element. The stopper protrusion and guide groove are in non-contact state when the rolling element rolls along the rolling surface, and the guide groove and stopper protrusion come into contact when the rolling element tries to move away from the rolling surface. It is configured. Therefore, when the rotational speed of the rotating body is slow, the centrifugal force generated in the rolling element is reduced, and when the rolling element is about to be displaced in an irregular direction, the displacement of the rolling element is caused by the stopper projection coming into contact with the guide groove. Therefore, it is said that the generation of abnormal noise and fine vibration due to collision between the rolling element and the rolling surface can be prevented. However, in such a configuration, when the displacement of the rolling element is restricted, it is difficult to restrict the displacement of the rolling element at the same location every time, so that the stopper protrusion and the guide groove are in a non-contact state. As a result, immediately after the rolling element rolls on the rolling surface, the phase of each rolling element varies, and as a result, the vibration damping ability of the centrifugal pendulum absorber may be lowered.

  The present invention has been made paying attention to the technical problem described above, and prevents abnormal noise and micro-vibration in a region where the rotational speed of the rotating body is low, and provides vibration damping capability in other rotational speed regions. An object of the present invention is to provide an excellent vibration damping device.

  In order to solve the above-described problem, the present invention provides a vibration damping device that is attached to a rotating body and attenuates torsional vibration generated in the rotating body, a rolling chamber that rotates integrally with the rotating body, When the rolling element accommodated in the rolling chamber and the centrifugal force generated in the rolling element is small, the rolling element is moved so as to be pressed against any inner wall surface of the rolling chamber, and the centrifugal A movable member that moves in a direction away from the rolling element when the force is large, and a surface of the movable member that faces the rolling element or any one of the inner wall surfaces against which the rolling element is pressed by the movable member And a recess that is retracted in the axial direction of the rotating body with respect to the rolling element and restrains the rolling element in the rolling direction.

  According to a second aspect of the present invention, in the first aspect of the present invention, the rolling element has a circular cross-sectional shape perpendicular to the rotation axis that is the center of the rolling, and the surface of the rolling element that faces the recess. The vibration damping device is characterized in that a curved surface that is convex with respect to the concave portion is formed.

  The invention according to claim 3 is the invention according to claim 1 or 2, wherein a plurality of the rolling chambers are provided, and the positions of the rolling elements constrained by the recesses in the plurality of rolling chambers are in the rolling direction. It is the vibration damping device characterized by being the same.

  According to a fourth aspect of the present invention, in the first or second aspect of the present invention, a rolling surface on which the rolling element rolls is formed in the rolling chamber, and the recess has the rolling element in the rolling direction. The portion facing the rolling element located near the center of the rolling surface is configured to be most receded in the axial direction so that it is fixed near the center of the rolling surface. This is a vibration damping device.

  According to the first aspect of the present invention, when the centrifugal force generated in the rolling element is small due to the rotation number of the rotating body being relatively low, the movable member moves the rolling element to any inner wall surface of the rolling chamber. Move so as to press. In addition, when the centrifugal force generated in the rolling element is large due to the relatively high number of rotations of the rotating body, the movable member moves in a direction away from the rolling element. A concave portion that is recessed with respect to the rolling element in the axial direction of the rotating body is formed on either the surface of the movable member facing the rolling element or the inner wall surface of the rolling chamber. Therefore, when the movable member moves so as to approach the rolling element, the rolling member is gradually moved so as to be collected in a recessed portion in the recess. Further, when the movable member moves toward the rolling element, the rolling element is moved to the recessed portion in the recess, and the rolling element is pressed against the inner wall surface of the rolling chamber by the movable member. Rolling is restrained and fixed. As a result, the location where the rolling elements are fixed in the rolling chamber can be the same or almost the same each time. Therefore, as described above, when the rolling of the rolling element is constrained and the rotating body rotates, a change in the balance of inertial mass generated in the rotating body can be suppressed. That is, rotation imbalance can be prevented or suppressed. On the other hand, when the rotational force of the rotating body is relatively high, if the centrifugal force generated in the rolling element increases, the movable member moves away from the rolling element to release the fixing of the rolling element. As a result, the rolling element becomes movable inside the rolling chamber, and when torsional vibration occurs in the rotating body, the rolling element starts rolling from the same location every time, and the rolling element rolls inside the rolling chamber. By reciprocating while moving, the torsional vibration is absorbed or damped. That is, when the rotational speed increases, the damper function is exhibited. As a result, a vibration damping device having excellent vibration damping capability can be obtained. In addition, as described above, when the centrifugal force generated in the rolling element is small, the free movement of the rolling element in the rolling chamber is restricted, so that the rolling element comes into contact with the inner wall surface of the rolling chamber, Accordingly, it is possible to prevent a situation in which abnormal noise is generated.

  According to the invention of claim 2, in addition to the effect similar to the effect of the invention of claim 1, the rolling element has a circular cross-sectional shape perpendicular to the rotation axis serving as the center of the rolling, and its side surface. Is formed with a curved surface that is convex with respect to the recess. Therefore, when a movable member moves so that it may approach a rolling element, a rolling element becomes easy to move to the recessed part in a recessed part. As a result, the location where the rolling elements are fixed in the rolling chamber can be the same or nearly the same each time.

  According to the invention of claim 3, in addition to the same effect as that of the invention of claim 1 or 2, the rotating body includes a plurality of rolling chambers. When the rolling element accommodated in each rolling chamber moves so that the movable member approaches the rolling element, as described above, the rolling element moves so as to be collected in the recessed portion in the recess, and finally the recess in the recess. It is fixed to the part. As a result, when the movable member moves so as to release the fixation of the rolling elements, each rolling element can start rolling from the same or substantially the same position. That is, the phase of each rolling element can be made uniform, and the vibration damping device excellent in vibration damping ability can be obtained.

  According to the invention of claim 4, in addition to the effect similar to the effect of the invention of claim 1 or 2, the recess has a portion facing the rolling element located near the center of the rolling surface of the rotating body. It is configured to retreat most in the axial direction. Therefore, the rolling elements that have moved so as to be collected in the recessed portion in the recess are located near the center of the rolling surface. As a result, when the rolling element is unfixed, the rolling element can be started to roll from the vicinity of the center of the rolling surface each time. In addition, since the rolling element can be fixed near the center of the rolling surface, immediately after the rolling element is released, the rolling element that has started rolling immediately contacts the inner wall surface of the rolling chamber or the like. Therefore, it is possible to prevent or suppress the occurrence of abnormal noise.

It is a fragmentary sectional view showing an example of the vibration damping device concerning this invention, and is a figure showing typically an example of the shape of a rolling room. It is sectional drawing which follows the II-II 'line | wire shown in FIG. It is sectional drawing which follows the III-III 'line shown in FIG. It is a figure which shows typically the example which improved the shape of the main-body part shown in FIG. In the example shown in FIG. 4, it is a figure which shows typically the example which improved the shape of the cover part. In the example shown in FIG. 5, it is a figure which shows typically the example which improved the shape of the rolling element. It is a figure which shows typically the example which provided the vibration damping device which concerns on this invention inside the torque converter which is a fluid power transmission device with a torque amplification effect | action.

  Next, the present invention will be described more specifically. The vibration damping device according to the present invention is a so-called pendulum type, and a rotating body corresponding to a weight capable of moving freely relative to the rotating body is provided on the rotating body that receives torque and rotates. It is made to hold. In the present invention, the vibration damping device can be configured to be provided inside the fluid transmission device, and in particular, provided in the fluid transmission device including the direct coupling clutch (lock-up clutch), the pressure for releasing the direct coupling clutch is set. The rolling elements are fixed by using them, and the rolling elements are unfixed by using a pressure for engaging the direct clutch.

  FIG. 7 shows an example in which a vibration damping device is provided inside a torque converter 1 which is a fluid transmission device having a torque amplifying action. The torque converter 1 shown here is similar to a torque converter widely installed in conventional vehicles. It has the composition of. That is, the pump impeller 2 that is a member on the input side is configured by attaching the pump blades 3 arranged in an annular shape to the inner surface of the pump shell 4, and the turbine runner 5 is disposed facing the pump impeller 2. Yes. The turbine runner 5 has a shape that is substantially symmetric with the pump impeller 2 and is configured by fixing a large number of annularly arranged turbine blades on the inner surface of an annular (or semi-doughnut-shaped) shell. ing. Accordingly, the pump impeller 2 and the turbine runner 5 are arranged to face each other on the same axis.

  A front cover 6 that covers the outer peripheral side of the turbine runner 5 is integrally joined to the outer peripheral end of the pump shell 4. As shown in FIG. 7, the front cover 6 is a so-called bottomed cylindrical member having a front wall surface facing the inner surface of the pump shell 4, and a shaft portion 7 is formed at the center of the outer surface of the front wall. The shaft portion 7 is formed so as to protrude, and is inserted into a tip portion of a crankshaft 8 of an engine (not shown), and is connected to the crankshaft 8 via a bearing 9 so as to be relatively rotatable. A drive plate 10 is attached to the crankshaft 8, and the drive plate 10 and the front cover 6 are connected via a damper 11.

  A cylindrical shaft 12 is integrally provided at the inner peripheral end of the pump shell 4, and the cylindrical shaft 12 extends to the back side of the pump shell 4 (the side opposite to the engine side). Not connected to the oil pump. A fixed shaft 13 having an outer diameter smaller than the inner diameter of the cylindrical shaft 12 is inserted into the cylindrical shaft 12, and a tip portion of the torque converter 1 surrounded by the pump shell 4 and the front cover 6 is inserted. It extends to the inside. The fixed shaft 13 is a hollow shaft-shaped part formed integrally with a fixed wall (not shown) that holds the oil pump, and is formed between the outer peripheral surface of the fixed shaft 13 and the inner peripheral surface of the cylindrical shaft 12. The space is a fluid flow path (that is, an oil path) 14.

  The distal end portion of the fixed shaft 13 is located on the inner peripheral side of the turbine runner 5 described above or on the inner peripheral side of the portion between the pump impeller 2 and the turbine runner 5. The inner race of the clutch 15 is spline-fitted. A stator 16 disposed between the inner peripheral portion of the pump impeller 2 and the inner peripheral portion of the turbine runner 5 facing the outer periphery of the one-way clutch 15 is attached. That is, in a state where the speed ratio between the pump impeller 2 and the turbine runner 5 is small, the rotation of the stator 16 is prevented by the one-way clutch 15 even if the oil flowing out from the turbine runner 5 acts on the stator 16. In the state where oil is fed to the pump impeller 2 by changing the flow direction of the oil and the speed ratio is large and the oil strikes the so-called back surface of the stator 16, the stator 16 is rotated so as not to disturb the oil flow. It is configured.

  On the inner peripheral side of the fixed shaft 13, an output shaft (input shaft of a transmission not shown) 17 is rotatably inserted, and the tip portion protrudes (beyons) the tip portion of the fixed shaft 13. A hub shaft 18 is spline-fitted to the outer periphery of the front end of the front cover 6 that extends near the inner surface of the front cover 6 and protrudes from the fixed shaft 13. The hub shaft 18 is formed with a flange-shaped hub 19 projecting to the outer peripheral side, and the above-described turbine runner 5 is connected to the hub 19 so as to be integrated with the hub 19.

  Further, a damper housing 20 is integrally provided on the hub shaft 18. The damper housing 20 constitutes a part of the vibration damping device according to the present invention, and includes an annular hollow portion along the rear surface (side surface on the front cover 6 side) of the turbine runner 5, and the hollow portion as a hub. And a flange-like portion connected to the shaft 18. As shown in FIG. 7, the hollow portion has a rectangular cross section with a shallow depth measured in the axial direction, and is a portion having an annular shape as a whole, a so-called main body portion 21 that opens to the front cover 6 side, and its It is comprised by the cover part 23 engage | inserted by the sealing material 22 at the opening edge part so that an airtight state was maintained and slidably fitted. The damper housing 20 and a member that rotates integrally with the damper housing 20 correspond to the rotating body in the present invention.

  FIG. 1 is a partial sectional view showing an example of a vibration damping device according to the present invention, and schematically shows an example of the shape of a rolling chamber. As shown in FIG. 1, the inner shape of the hollow portion described above is such that the outer peripheral surface and the inner peripheral surface are formed as arc surfaces, and the outer peripheral surface and the inner peripheral surface An annularly partitioned portion is a rolling chamber 24. The outer peripheral surface can be formed as a curved surface that changes continuously in the radial direction. In each of the rolling chambers 24, a rolling element 25 that can roll in the circumferential direction of the rotation shaft described above is housed along the outer peripheral surface.

  2 is a cross-sectional view taken along the line II-II ′ shown in FIG. 1, and FIG. 3 is a cross-sectional view taken along the line III-III ′. As shown in FIGS. 2 and 3, the rolling element 25 has a cylindrical shape as an example, and a convex arc surface or a hemispherical curved surface is formed on the upper surface and the bottom surface thereof. Therefore, the rolling element 25 is formed so that the shape of the cross section orthogonal to the rolling axis that is the center of the rolling is circular. The outer diameter of the rolling element 25 is set to be smaller than the interval between the outer peripheral surface forming the rolling chamber 24 and the inner peripheral surface and larger than the interval between both sides of the rolling chamber 24. That is, the rolling elements 25 are configured to be movable in the left-right direction in FIG. 1 inside each rolling chamber 24. Note that the outer peripheral surface of each rolling chamber 24 is a rolling surface 21A that contacts when the rolling element 25 receives a centrifugal force and rolls along the rolling element 25, and thus the rolling surface. The left and right surfaces starting from the center of 21A are configured as, for example, toroidal surfaces.

  Further, the lid portion 23 corresponds to a movable member in the present invention, and is configured to be separated from the rolling element 25 when moved to the opening end side of the hollow portion. On the contrary, in a state where the lid portion 23 is pushed into the hollow portion, the rolling element 25 is sandwiched between the bottom surface of the hollow portion, that is, the inner wall surface 21B of the main body portion 21 to fix the rolling element 25. It is configured. Further, the inner surface 23 </ b> A of the lid portion 23 is formed as a curved surface that retreats in the axial direction of each rotating body described above with respect to the rolling element 25. More specifically, the inner surface 23A of the lid portion 23 has a central portion when the rolling element 25 is located near the central portion of the rolling surface 21A as shown in FIGS. 2 and 3, for example. A portion facing the rolling element 25 located in the vicinity is formed as a curved surface that is the most depressed with respect to the rolling element 25. The inner surface 23A of the lid 23 may be formed in a tapered shape so that the portion facing the rolling element 25 located near the center of the rolling surface 21A is most depressed. Thus, the inner surface 23A of the lid portion 23 formed as a curved surface recessed with respect to the rolling element 25 corresponds to the concave portion in the present invention.

  A lockup clutch (direct coupling clutch) 26 is provided between the damper housing 20 and the front cover 6. The lock-up clutch 26 is for transmitting torque between the driving side member and the driven side member without passing through a fluid, as is conventionally known, and is an example shown in FIG. The hub shaft 18 and the front cover 6 are connected to each other. That is, the lock-up clutch 26 is mainly composed of a disk-shaped lock-up piston 27 disposed between the vibration damping device and the inner surface of the front cover 6, and the lock-up piston 27 is composed of the hub shaft described above. 18 is spline-fitted so as to be movable in the axial direction and integrated with the hub shaft 18 in the rotational direction. Further, a friction material 28 that is pressed against the front cover 6 and generates a frictional force is attached to the outer peripheral side of the side surface of the lockup piston 27 that faces the front cover 6 as much as possible. Further, the outer diameter of the lock-up piston 27 is an outer diameter that is slightly smaller than the inner diameter of the front cover 6, and the outer peripheral end thereof extends in the axial direction along the inner peripheral surface of the front cover 6. A cylindrical portion 29 is formed. Therefore, the lock-up piston 27 is pushed to the right in FIG. 7 and its friction material 28 comes into contact with the front cover 6 so that it is engaged and transmits torque between the front cover 6 and the hub shaft 18. In addition, the friction member 28 is separated from the front cover 6 by being pushed back in the left direction in FIG.

  And the cover part 23 which is a movable member mentioned above is connected with the back surface (surface on the opposite side to the surface to which the friction material 28 is attached) of the lockup piston 27. As shown in FIG. That is, the lid portion 23 is configured to move back and forth in the axial direction together with the lockup piston 27.

  Further, the oil passage for supplying and discharging the hydraulic pressure for engaging and releasing the lockup clutch 26 will be described. The output shaft 17 described above is formed with an oil passage 30 along its central axis. The oil passage 30 opens at the tip of the output shaft 17. Further, there is a slight gap between the inner surface of the front cover 6 and the lock-up piston 27, and therefore the oil passage 30 is opened and communicated with the gap. On the other hand, the oil path 14 between the cylindrical shaft 12 and the fixed shaft 13 described above communicates with a portion on the back side of the lockup piston 27, that is, a portion in which the turbine runner 5 is accommodated.

  Therefore, assuming that the oil passage 14 is the engagement oil passage 14 and the oil passage 30 formed in the output shaft 17 is the release oil passage 30, the hydraulic pressure of the engagement oil passage 14 is reduced to that of the release oil passage 30. By making the pressure higher than the hydraulic pressure, the pressure on the back side of the lock-up piston 27 becomes higher than the pressure between the lock-up piston 27 and the pressure between the front cover 6 and as a result, the lock-up piston 27 is pushed to the front cover 6 side. It is pressed against the inner surface of the cover 6. That is, the lockup clutch 26 is engaged. As the lock-up piston 27 moves in this manner, the lid portion 23 in the vibration damping device moves in the right direction in FIG. 7, so that the pinching of the rolling elements 25 is released. On the contrary, when the hydraulic pressure of the engagement oil passage 14 is made lower than the hydraulic pressure of the release oil passage 30, the pressure between the front cover 6 and the pressure on the back side of the lockup piston 27 becomes higher. The up piston 27 is pushed away from the front cover 6, and the friction material 28 is separated from the inner surface of the front cover 6. That is, the lockup clutch 26 is released. As the lock-up piston 27 moves in this manner, the lid portion 23 of the vibration damping device moves in the left direction in FIG. 7, so that the rolling element 25 is sandwiched between the main body portion 21 and the lid portion 23 and moved. Not to be fixed. When the lockup clutch 26 is mounted on the vehicle, the engagement / release control is a map in which the engagement region is defined by parameters indicating the vehicle running state such as the vehicle speed and the accelerator opening. The control is executed by controlling the oil pressure of the oil passages 14 and 30 or the supply / discharge of the oil pressure based on the map, and the control is the same as the conventional control executed in the vehicle. It's okay.

  Next, the operation of the vibration damping device configured as described above will be described. When the torque converter 1 is mounted on a vehicle and the vehicle is stopped, the engine speed is low, or when the engine output torque or accelerator opening is large, the vibration of the vehicle body In order to reduce booming noise and the like, the lockup clutch 26 is controlled to the released state. Specifically, the hydraulic pressure supplied from the release oil passage 30 is increased, and as a result, the hydraulic pressure on the front cover 6 side with the lock-up piston 27 interposed therebetween is changed to the pressure on the turbine runner 5 side opposite thereto. It becomes higher and the lockup piston 27 is pushed away from the inner surface of the front cover 6. Thus, the friction material 28 attached to the lock-up piston 27 is separated from the inner surface of the front cover 6, and the transmission of torque between the two is interrupted. That is, the lockup clutch 26 is released.

  When the lock-up piston 27 is pushed back in the direction away from the inner surface of the front cover 6 in this manner, the lid portion 23 connected to the back surface of the lock-up piston 27 is pushed into the rolling chamber 24, and the rolling chamber The width of 24 (depth of the hollow portion described above) is reduced. As described above, the inner surface 23 </ b> A of the lid part 23 is a concave curved surface that is recessed with respect to the rolling element 25, so that the rolling element 25 becomes an inner surface as the lid part 23 approaches the rolling element 25. It gradually moves on the rolling surface 21A so as to be collected in the depression 23A. Further, when the lid portion 23 is pushed into the rolling chamber 24, the rolling element 25 is moved to a position facing the most depressed portion on the inner surface 23A. That is, it is moved near the center of the rolling surface 21A. And the rolling element 25 is fixed by being pinched | interposed between the cover part 23 and the inner wall face of the rolling chamber 24, and the rolling is restrained.

  Since the engine torque is transmitted to the front cover 6 via the drive plate 10, the pump impeller 2 rotates together with the front cover 6 to generate a spiral flow of oil. The oil is supplied to the turbine runner 5 from the outer peripheral side of the pump blade 3, and the turbine runner 5 is rotated by the kinetic energy of the oil. In this way, power is transmitted from the drive-side pump impeller 2 to the driven-side turbine runner 5. Since the turbine runner 5 and the above-described damper housing 20 are integrated via the hub shaft 18, power is transmitted from the turbine runner 5 to the output shaft 17 and output, and the damper housing 20 is connected to the turbine runner 5. Rotate with. In that case, even if the rotational speed of the damper housing 20 fluctuates due to torque fluctuation or the like, the rolling elements 25 housed in the rolling chamber 24 inside are fixed to the inner surface of the rolling chamber 24. It is possible to prevent or suppress the rolling element 25 from coming into contact with the inner surface of the rolling chamber 24 and the generation of abnormal noise accompanying it. Further, since each rolling element 25 is fixed in the same manner in the vicinity of the center portion of the rolling surface 21A, it is possible to suppress a change in the balance of inertial mass that occurs in the damper housing 20 when the damper housing 20 rotates. it can.

  On the other hand, when the rotational speed of the engine or the input rotational speed of the torque converter 1 becomes high due to an increase in the vehicle speed of the vehicle on which the torque converter 1 is mounted, the torque amplifying effect of the torque converter 1 is more than Since it is necessary to improve the torque transmission efficiency, the lockup clutch 26 is engaged. Specifically, the hydraulic pressure supplied from the above-described engagement oil passage 14 is increased or the hydraulic pressure of the release oil passage 30 is decreased, and as a result, the turbine runner 5 is disposed with the lock-up piston 27 interposed therebetween. The hydraulic pressure on the applied side becomes higher than the hydraulic pressure on the front cover 6 side, and the lockup piston 27 is pushed toward the front cover 6 by the hydraulic pressure difference. When the lockup piston 27 moves to the front cover 6 side in this way, the friction material 28 attached to the front surface (side surface on the front cover 6 side) is pressed against the inner surface of the front cover 6. That is, the lock-up clutch 26 is engaged, and torque is transmitted by the frictional force between the friction material 28 and the front cover 6. Since the lock-up piston 27 is spline-fitted to the hub shaft 18 and the turbine runner 5 is attached to the hub shaft 18, the lock-up piston 27 is connected to the turbine runner 5 or the output shaft 17 via the lock-up clutch 26 from the front cover 6. Power is transmitted directly. That is, power is transmitted without slipping due to the fluid, and power transmission efficiency is improved.

  In this engaged state, the lid 23 moves together with the lock-up piston 27 in the direction of increasing the width or volume of the rolling chamber 24, that is, in the right direction in FIG. For this reason, the load that presses the rolling element 25 against the inner surface of the rolling chamber 24 does not act, so the fixing of the rolling element 25 is released. As described above, the rolling elements 25 are fixed near the center of the rolling surface 21A in a state where the lock-up clutch 26 is engaged. In each of the rolling chambers 24, the rolling is started from the vicinity of the central portion of the rolling surface 21A. That is, the phases of the rolling elements 25 that reciprocate on the rolling surface 21A while rolling by torsional vibration can be made uniform. Therefore, when the reciprocating motion in the rotational direction occurs in the turbine runner 5 and the damper housing 20 integrated with the turbine runner 5 due to torsional vibration, the rolling elements 25 move relative to the damper housing 20 with delay in the rolling chambers 24. Thus, the torsional vibration is attenuated by the relative movement of the rolling elements 25 in the state where the phases of the rolling elements 25 are aligned.

  As described above, in the low rotational speed state where the necessity for the vibration damping action is low, the rolling elements 25 are fixed inside the rolling chamber 24, so that the generation of abnormal noise can be prevented or suppressed. Further, when the number of rotations increases and the necessity of the vibration damping action increases, the fixing of each rolling element 25 is released by the lock-up hydraulic pressure, and the rolling elements 25 are all reciprocated to cause a vibration damping action. Can do. Further, when the rolling element 25 is released from the fixed state, the rolling element 25 starts rolling from the vicinity of the center portion of the rolling surface 21A. Therefore, immediately after the rolling is started, the rolling element 25 rolls in the rolling direction. In the example shown in FIG. 1 and FIG. 2 in the inner wall surface of the chamber 24, it is possible to prevent or suppress the generation of abnormal noise and fine vibration due to collision with the inner wall surfaces on both sides of the rolling chamber 24. In the above-described configuration, the rolling chamber 24 is sealed in an airtight state by the sealing material 22, and air at about atmospheric pressure is sealed therein. Accordingly, when the lid portion 23 moves into the rolling chamber 24, the internal pressure of the rolling chamber 24 increases, but the hydraulic pressure for releasing the lock-up clutch 26 is higher than the internal pressure of the rolling chamber 24. Therefore, there is no problem in fixing the rolling element 25. As a result, the rolling elements 25 are fixed at the same or substantially the same position every time. When the fixing is released, each rolling element 25 starts rolling from the same or almost the same position every time. Since the phases of the reciprocating motions of the rolling elements 25 are aligned, a vibration damping device having excellent vibration damping ability can be obtained immediately after the rolling elements 25 are fixed.

  FIG. 4 schematically shows an example in which the shape of the main body shown in FIG. 2 is improved. The example shown here is the inner wall surface of the main body 21, and each rotating body with respect to the rolling element 25 on the inner wall surface 21 </ b> B on the side where the rolling element 25 is pressed, similarly to the inner surface 23 </ b> A of the lid 23 described above. This is an example in which a curved surface retreated in the axial direction is formed. As shown in FIG. 4, the inner wall surface 21 </ b> B has a portion facing the rolling element 25 located near the center when the rolling element 25 is located near the center of the rolling surface 21 </ b> A. It is formed as a curved surface that is most recessed with respect to the rolling element 25. The inner wall surface 21B may be formed in a tapered shape so that a portion facing the rolling element 25 located near the center of the rolling surface 21A is most depressed.

  FIG. 5 schematically shows an example in which the shape of the lid is improved in the example shown in FIG. The example shown here is an example in which the inner surface 23A of the lid portion 23 is formed in a linear shape.

  FIG. 6 schematically shows an example in which the shape of the rolling element is improved in the example shown in FIG. The example shown here is an example in which the surface of the rolling element 25 facing the inner surface 23A of the lid portion 23 is formed in a linear shape in the example shown in FIG.

  Therefore, in the vibration damping device configured as shown in FIG. 4 to FIG. 6, when hydraulic pressure is supplied to engage the lockup clutch 26 and the lockup clutch 26 is engaged, as in the above-described example, Along with this, the lid 23 moves in the direction of increasing the width or volume of the rolling chamber 24. Therefore, the fixing of the rolling element 25 is released. That is, the rolling element 25 functions to attenuate torsional vibrations by moving in the rolling chamber 24.

  On the other hand, when the lockup clutch 26 is released due to an increase in engine load or the like, the engagement pressure does not act on the lockup clutch 26. Therefore, as described above, the lock-up piston 27 is pushed back in the direction away from the inner surface of the front cover 6, and accordingly, the lid portion 23 connected to the back surface of the lock-up piston 27 is placed inside the rolling chamber 24. The width of the rolling chamber 24 is reduced by being pushed in. As shown in FIGS. 4 to 6, the inner wall surface 21 </ b> B of the main body portion 21 is a concave curved surface that is recessed with respect to the rolling element 25, and thus is similar to the configuration shown in FIGS. 1 to 3. 4 to 6 also, the rolling member 21 is gradually collected on the inner wall surface 21B or the inner surface 23A so that the rolling member 25 is gathered in the depression of the inner wall surface 21B or the inner surface 23A as the lid 23 approaches the rolling member 25. Move to. Further, when the lid portion 23 is pushed into the rolling chamber 24, the rolling element 25 is moved to a position facing the most depressed portion of the inner wall surface 21B or the inner surface 23A. That is, it is moved near the center of the rolling surface 21A. And the rolling element 25 is fixed by being pinched | interposed between the cover part 23 and the inner wall face of the rolling chamber 24, and the rolling is restrained. Therefore, even if a temporary fluctuation occurs in the rotational speed of the turbine runner 5, the rolling element 25 does not move in the rolling chamber 24, so that it is possible to avoid or suppress a situation such as abnormal noise or slight vibration. As in the example shown in FIGS. 1 to 3, the necessary vibration damping function can be exhibited immediately after the rolling element 25 is fixed.

  The present invention can be applied to a fluid transmission device having a drive-side impeller, a driven-side impeller, and a direct coupling clutch. The fluid transmission device according to the present invention is other than the above-described torque converter having a torque amplifying effect. The fluid transmission device may be used. Further, the movable member only needs to be configured to operate by hydraulic pressure that engages the direct coupling clutch to release the fixed rolling element. Therefore, the rolling element, the rolling chamber, or the movable member is incorporated in the fluid transmission device. It does not have to be.

  DESCRIPTION OF SYMBOLS 20 ... Damper housing, 21 ... Main-body part, 21A ... Rolling surface, 21B ... Inner wall surface by which a rolling element is pressed, 23 ... Lid part, 23A ... Inner surface of a lid part, 24 ... Rolling chamber, 25 ... Rolling body .

Claims (4)

In a vibration damping device that is attached to a rotating body and attenuates torsional vibration generated in the rotating body,
A rolling chamber that rotates integrally with the rotating body;
A rolling element housed in the rolling chamber so as to be capable of rolling;
When the centrifugal force generated in the rolling element is small, the rolling element is moved so as to be pressed against any inner wall surface of the rolling chamber, and when the centrifugal force is large, the rolling element is moved away from the rolling element. A movable member that
The movable member is formed on a surface of the movable member facing the rolling element or any one of the inner wall surfaces against which the rolling element is pressed by the movable member. A vibration dampening device comprising a recess for restraining the rolling element in the rolling direction. The rolling element has a circular cross-sectional shape perpendicular to the rotation axis that is the center of the rolling,
The vibration damping device according to claim 1, wherein a curved surface that is convex with respect to the concave portion is formed on a surface of the rolling element that faces the concave portion.   The position in the rolling direction of the said rolling element which has several said rolling chambers and is restrained by the said recessed part in these rolling chambers is the same of Claim 1 or 2 characterized by the above-mentioned. Vibration damping device. A rolling surface on which the rolling element rolls is formed inside the rolling chamber,
The concave portion has a portion facing the rolling element located near the center of the rolling surface such that the rolling element is fixed in the rolling direction near the center of the rolling surface. The vibration damping device according to claim 1, wherein the vibration damping device is configured to be most retracted.

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