JP2013185598A - Torsional vibration damping device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a torsional vibration damping device in which a space for many rolling elements to reciprocate can be secured by suppressing the rolling elements from contacting or colliding with each other, and thus damping performance can be improved.SOLUTION: In a torsional vibration damping device 1, a rolling surface 14 having a curvature center at a part apart form the rotation center Oof a rotator 7 is formed in the rotator 7, and a plurality of rolling elements 11, 17 that are contacted on the rolling surface 14 by a centrifugal force due to the rotation with the rotator 7 and that rolls on the rolling surface 14 by torsional vibration of the rotator 7 are provided. The torsional vibration damping device 1 includes guide mechanisms 15, 19 that allows each of the rolling elements 11, 17 to roll in a torsional direction with respect to a circumferential direction of the rotator 7 so that each of the rolling elements 11, 17 does not contact each other when each of the rolling elements 11, 17 roll on the rolling surface 14 by torsional vibrations.

Description

  The present invention relates to an apparatus for attenuating torsional vibration of a rotating body such as a crankshaft and a power transmission shaft, and in particular, a mass body that reciprocates due to torsional vibration is attached to the rotating body, The present invention relates to an apparatus configured to damp body torsional vibrations.

  Rotating bodies such as a drive shaft for transmitting torque generated by a driving force source are caused by fluctuations in the input torque itself and fluctuations in load torque caused by driving devices connected to the rotating body. And vibration may occur. Such torque fluctuations act as torsional vibrations on the rotating body. Devices for attenuating this type of vibration have been developed, examples of which are described in Patent Document 1 and Patent Document 2.

  In the centrifugal pendulum type dynamic vibration absorber described in Patent Document 1, a raceway surface is formed on the inner wall surface of a rolling chamber formed on the outer peripheral side of the rotating body, and the rolling element reciprocates on the raceway surface by torsional vibration. It is configured to attenuate the torsional vibration by moving. A protrusion is formed on the outer peripheral surface of the rolling element, and a groove that fits the protrusion is formed on the raceway surface. In addition, when the rolling element rotates together with the rotating body and centrifugal force acts on the rolling element and no force in the circumferential direction of the rotating body acts, the rolling element moves relative to the rotation center of the rotating body on the raceway surface. Moved to the farthest position. In the following description, this position may be referred to as a neutral position. In the centrifugal pendulum type dynamic vibration absorber configured as described above, when the inertial force in the circumferential direction is generated in the rolling element due to the torsional vibration of the rotating body and the reciprocating motion is performed on the raceway surface, the protrusion is fitted in the groove. Thereby, the movement of the rolling element in the rotation axis direction of the rotating body is suppressed. Therefore, it is said that the frictional force generated between the rolling elements and the rolling chambers can be reduced, and the vibration damping performance can be improved.

  In addition, the flywheel described in Patent Document 2 rolls on the rolling surface formed on the inner wall surface of the rolling chamber formed on the inner wall surface due to the rotational fluctuation of the flywheel. In addition, a damper mass whose center axis of rolling is inclined with respect to the rotation center axis of the flywheel is accommodated. In the flywheel described in Patent Document 2, since the acting direction of the centrifugal force generated in the damper mass and the central axis direction of the damper mass are not orthogonal to each other, there is a component force to press the damper mass to one side of the rolling chamber. It is generated and reciprocates in a state where the damper mass is brought into contact with one side surface by the component force.

JP 2010-249297 A JP-A-6-294446

  In the centrifugal pendulum type dynamic vibration absorber described in Patent Document 1, if the outer diameter of the rolling element is increased, it advantageously works to improve the vibration damping performance due to the increase in the mass of the rolling element. May approach the center of rotation of the rotating body, and the desired vibration damping performance may not be obtained. In addition, in order to obtain the desired vibration damping performance due to the reciprocating motion of the rolling elements, for example, a space for avoiding contact or collision between adjacent rolling elements must be secured, and as a result, the apparatus is large. There is a possibility of becoming. If the rolling elements are connected to each other instead of securing such a space, the above-described contact and collision can be avoided, but the reciprocating movement of each rolling element is not hindered, that is, the reciprocating movement is not affected. It is difficult to connect without changing the order. On the other hand, if the rolling elements are formed of a dense metallic material such as gold, lead, actinides or their oxides, the mass of the rolling elements can be increased, but the material cost is increased and the durability is increased. There is still room for improvement, such as a shortage or difficult handling.

  The present invention has been made paying attention to the above technical problem, and by suppressing contact and collision between the rolling elements, a space for reciprocating motion of many rolling elements can be secured, and consequently An object of the present invention is to provide a torsional vibration damping device capable of improving the vibration damping performance.

  In order to achieve the above object, the invention according to claim 1 is characterized in that a rolling surface having a center of curvature is formed on the rotating body at a location deviating from the rotating center of the rotating body, and the centrifugal operation is performed by rotating together with the rotating body. In a torsional vibration damping device comprising a plurality of rolling elements that are brought into contact with the rolling surface by force and roll on the rolling surface by torsional vibration of the rotating body, the rolling elements are moved by the torsional vibration. When rolling on a rolling surface, a guide mechanism is provided for rolling the rolling elements in a direction twisted with respect to the circumferential direction of the rotating body so that the rolling elements do not contact each other. It is characterized by this.

  According to a second aspect of the present invention, in the first aspect of the invention, the guide mechanism is provided on a convex portion provided on one of the outer peripheral edge of the rolling element and the rolling surface, and on the other. A vibration damping device comprising a guide groove fitted to the convex portion.

  The invention of claim 3 is the invention of claim 2, wherein the convex portion is formed with a tapered inclined surface, and a surface facing the tapered surface is formed in the guide groove. This is a vibration damping device.

  According to this invention, it becomes possible to arrange a rolling element newly in the space provided in order to avoid contact between rolling elements, As a result, since the total mass of a rolling element can be increased, it vibrates. Attenuation performance can be improved. In this way, the contact between the rolling elements can be prevented or suppressed. For example, even when the amplitude of the rolling elements is large due to the low order of the torsional vibration of the object to be controlled, the desired vibration damping performance can be achieved. Can be obtained. Moreover, since the guide groove is fitted to the convex portion, the rolling direction of the rolling element can be maintained. That is, even when an external force that changes the angle between the circumferential direction of the rotating body and the direction in which the rolling element rolls acts on the rolling element, the intended rolling direction can be maintained. it can. Moreover, it replaces with newly arrange | positioning a rolling element in the space mentioned above, and vibration damping performance can also be improved by enlarging each rolling element and increasing the mass.

An example of torsional vibration damping according to the present invention is schematically shown, wherein (a) is a front view of the torsional vibration damping device, and (b) is an enlarged sectional view of a part of the torsional vibration damping device. It is a figure which expands and shows a part of torsional vibration damping device shown in FIG. It is a figure which shows typically the relative position of a convex part and the surface of the outer peripheral side of a rolling chamber. It is a figure which shows typically the state which the rolling element is reciprocating. It is a figure which shows typically the example which changed a part of structure of the torsional vibration damping device shown in FIG. It is a figure which shows typically the other example which changed a part of structure of the torsional vibration damping device shown in FIG.

  Next, the present invention will be described more specifically. FIG. 1 schematically shows an example of a torsional vibration damping device 1 according to the present invention, where (a) is a front view of the torsional vibration damping device 1 and (b) is a part of the torsional vibration damping device 1. FIG. FIG. 2 shows an enlarged part of the torsional vibration damping device 1 shown in FIG. A cylindrical outer member 3 is provided concentrically with a cylindrical inner member 2 that rotates integrally with a rotation shaft such as an output shaft of an engine (not shown) or an input shaft of a transmission. An annular spacer 4 is fitted on the outer peripheral side of the inner member 2, and the spacer 4 reduces the hollow portion formed between the outer peripheral surface of the inner member 2 and the inner peripheral surface of the outer member 3. ing. The inner member 2 and the spacer 4 are connected by, for example, a bolt 5. The hollow portion accommodates the rolling elements described below, secures the rolling region by partitioning, and further forms a rolling surface.

  A plurality of protrusions 6 are formed on the outer peripheral side of the spacer 4 at regular intervals in the circumferential direction. The protrusions 6 are formed in a circular or semicircular shape as an example, and as shown in FIG. 1A and FIG. 2, the radius of the rotation shaft among the protrusions 6 and the inner peripheral edge of the hollow portion described above. The rolling elements are arranged between the outer peripheral surface in the direction and the movement of the rolling elements in the radial direction of the rotation shaft is suppressed. Although not shown in detail, a cover member that connects the inner member 2 and the outer member 3 and covers the hollow portion described above is provided, and these inner member 2, outer member 3, spacer 4, etc. The rotating body 7 in the invention is configured.

In the example shown in FIG. 1, the surface 8 on the outer peripheral side in the radial direction of the rotating body 7, that is, the inner peripheral surface 8 of the outer member 3 is continuously uneven in the radial direction of the rotating body 7. It is formed as a changing curved surface. A hollow portion is defined by a portion where the distance between the outer peripheral surface 8 and the outer peripheral surface 9 of the spacer 4 is narrow, and the portion thus partitioned is a rolling chamber 10. Each rolling element 11 is accommodated in each rolling chamber 10. The rolling element 11 is rotated together with the rotating body 7 and is moved to the outer peripheral surface 8 of each rolling chamber 10 by the centrifugal force acting thereon. The torsional vibration of the rotating body 7 causes the rolling element 11 to move in the circumferential direction of the rotating body 7. of the inertia forces occur, being guided by the predetermined angle theta ₁ only twisted direction with respect to the circumferential direction of the rotary member 7 by a guide mechanism to be described below, i.e. on the rolling surface to be described later is tilted Roll.

  As shown in FIG. 1B, the rolling element 11 includes a cylindrical shaft portion 11a and a disc portion 11b that is integrally provided on both sides thereof and has an outer diameter larger than the outer diameter of the shaft portion 11a. , 11c. A surface 11e on the shaft portion 11a side of the disc portion 11c faces the surface 11d on the shaft portion 11a side of the disc portion 11b, and a groove portion 12 is formed between these surfaces 11d and 11e. Yes. When the convex part 13 formed in the outer peripheral surface 8 of the rolling chamber 10 fits into the groove part 12, the rolling direction of the rolling element 11 is guided. The convex part 13 is formed in the rectangle curved along the shape of the outer peripheral surface 8 as an example. Further, the protrusion 6 is also fitted in the groove 12. That is, the width of the groove portion 12 is formed larger than the width of the convex portion 13 and the protruding portion 6. The groove 12 corresponds to the guide groove in the present invention.

  Further, the upper surface of the convex portion 13 is in contact with the outer peripheral surface of the shaft portion 11 a to form a rolling surface 14. The height of the convex portion 13 is the same as or slightly longer than the length from the outer peripheral surface of the shaft portion 11a to the outer peripheral edge of each of the disk portions 11b and 11c. These groove portions 12 and convex portions 13 correspond to the guide mechanism 15 in the present invention. In the example shown here, the rolling surface 14 is formed as an arc surface having a curvature radius smaller than the radius of the rotating body 7 and a constant curvature as an example.

The relative positions of the convex portions 13 and the outer peripheral surface 8 will be described. As shown in FIG. 3, the convex portion 13 has a direction along the rolling surface 14 in the circumferential direction of the rotating body 7 or rotation. It is formed on the outer peripheral surface 8 so as to be twisted by a predetermined angle θ _{1 with} respect to the surface rp. That is, the rolling element 11 rolls in a direction twisted by a predetermined angle θ _{1 with} respect to the circumferential direction of the rotating body 7. Therefore, the raceway surface op of the rolling element 11 formed by connecting the position of the center of gravity G of the rolling element 11 that changes by rolling on the rolling surface 14 is predetermined with respect to the rotation surface rp of the rotating element 7. They intersect at an angle of θ ₁ . The predetermined angle θ ₁ , that is, the inclination angle θ ₁ , as an example, the torsional vibration to be controlled acts on the rotating body 7, and the rolling element is generated by the inertial force IF generated in the rolling element 11 in the circumferential direction of the rotating body 7. 11 is less than the maximum angle at which 11 can roll. In the example shown in FIG. 3, the maximum angle is the angle θ formed by the orbital plane op and the plane p passing through the intersection or line of the two planes op and rp described above and parallel to the rotation axis of the rotating body 7. ₂ is a so-called friction angle. Therefore, the range of the inclination angle θ ₁ described above is an angle range obtained by subtracting the angle θ ₂ formed from the angle (π / 2) formed by the rotation surface rp and the plane p. Since the protrusion 6 is also configured to fit into the groove 12, the protrusion 6 is also inclined by the angle θ _{1 with} respect to the rotation surface rp of the rotating body 7.

Next, the operation of the torsional vibration damping device 1 configured as described above will be described. The rotating body 11 accommodated in the rolling chamber 10 rotates together with the rotating body 7 as the rotating body 7 rotates. Specifically, since the rolling element 11 is pressed against the rolling surface 14 by centrifugal force, the rolling element 11 revolves around the rotation center O ₀ of the rotating body 7. Since the rolling surface 14 is a curved surface having a radius of curvature smaller than the radius of the rotating body 7, a line connecting the center of the rolling surface 4, that is, the center of curvature of the rolling surface 4 and the rotational center O ₀ of the rotating body 7. The position intersecting the rolling surface 4 is the position farthest from the center O ₀ of the rotating body 7. Therefore, in a state where centrifugal force is applied to the rolling element 11 and no force in the circumferential direction of the rotating body 7 is applied, the rolling element 11 is the most from the rotation center O ₀ of the rotating body 7 in the rolling surface 4. Moved to a distant position. 1 and 2 show this state. This position is referred to as a neutral position. At this neutral position, the centers of gravity of the rolling elements 11 are arranged on a line connecting the rotation center O ₀ of the rotating body 7 and the center of curvature of the rolling surface 14.

When torsional vibration acts on the rotating body 7, a force acts so as to twist the rotating shaft integral with the rotating body 7. That is, an inertial force acts on the rolling element 11 as angular acceleration occurs in the rotating body 7. The rolling direction of the rolling element 14 is guided by the guide mechanism 15, and is twisted by the inclination angle θ _{1 with} respect to the rotation surface rp of the rotating body 7. Therefore, even if a plurality of rolling elements 14 are attached to the rotating body 7, the rolling elements 14 can reciprocate on the rolling surface 14 without contacting each other. This state is shown in FIG.

The force acting on the rolling element 14 whose rolling direction is guided by the guide mechanism 15 will be described. Since the raceway surface op of the rolling element 11 intersects with the rotation surface rp of the rotating body 7 at a predetermined angle θ ₁ , an inertial force IF is generated in the rolling element 11, for example, rolling on one side. When doing, as shown in FIG. 3, the side surface 11d of the disc part 11b and the side surface 13a of the convex part 13 which opposes this contact. Inertial force IF is as shown in FIG. 3, the rolling and component force in the direction cf ₁ for rolling of the rolling elements 11 can be decomposed into a component force cf ₂ in the direction perpendicular to the component force cf _1. Since the component force cf ₂ acts to press the rolling element 11 against the convex portion 13, the rolling element 11 has a side surface in addition to the frictional force f ₁ generated between the outer peripheral surface of the shaft portion 11 a and the rolling surface 14. frictional force _{f 2} also acts occurring between 11d and side 13a. That is, the rolling element 11 rolls along the side surface 13a while slipping between the side surface 11d and the side surface 13a. Therefore, the inclination angle θ ₁ is set so that the component force cf ₁ is larger than the friction force obtained by combining the friction forces f ₁ and f ₂ . Although not shown in detail, when an inertial force having a direction opposite to the above-described inertial force IF is generated on the rolling element 11 and rolls to the other side, the side surface 11e of the disc portion 11c faces the side. The side surface 13b of the convex part 13 which contacts is in contact. Based on the same principle, the rolling element 11 rolls along the side surface 13b while sliding between the side surface 11e and the side surface 13b.

FIG. 5 schematically shows an example in which a part of the configuration of the torsional vibration damping device 1 shown in FIG. 1 is changed. In the example shown here, the convex portion of the guide mechanism according to the present invention is formed on the rolling element 11. This is an example. As shown in FIG. 5, the shaft portion 11a of the rolling element 11 is formed with a large diameter, and the disk portions 11b and 11c are formed with a small diameter. Therefore, the outer peripheral side of the shaft part 11a protrudes from the outer peripheral edge of each disk part 11b, 11c. The protruding portion corresponds to the convex portion of the guide mechanism in the present invention, and the groove portion 12 that fits into the convex portion is formed on the outer peripheral surface 8. That is, the width of the groove portion 12 is formed wider than the width of the shaft portion 11a, and the direction along the groove is twisted by a predetermined angle θ _{1 with} respect to the circumferential direction of the rotating body 7 or the rotation surface rp. So that it is inclined. Moreover, the groove depth is shorter than the height from the outer peripheral edge of each disk part 11b, 11c to the outer peripheral edge of the axial part 11a. As described above, in the example illustrated in FIG. 5, the outer peripheral portion of the shaft portion 11 a is configured to fit into the groove portion 12 and roll with the bottom surface of the groove portion 12 as the rolling surface 14. In addition, you may comprise so that the outer peripheral surface of the disc parts 11b and 11c may roll on the surface (namely, outer peripheral surface 8) of the both sides of the groove part 12 in the outer peripheral surface 8. FIG. On the other hand, the protruding portion 6 is formed by a pair of substantially circular disk portions and a groove portion formed between the disk portions and into which the shaft portion 11a is fitted. The protrusion 6 shown in FIG. 5 is also inclined by the angle θ _{1 with} respect to the rotation surface rp of the rotating body 7.

Therefore, even in the rolling element 11 configured as shown in FIG. 5, the rolling direction of the rolling element 14 is guided by the guide mechanism 15, so even if a plurality of rolling elements 14 are attached to the rotating body 7, Each rolling element 14 can reciprocate on the rolling surface 14 without contacting each other. Also, rolling if the element 11 is an inertial force IF rolls, for example, in one side of the resulting frictional force f ₂ in contact with one side surface 12a forming the side 11f and the groove 12 of the shaft portion 11a is Arise. That is, the rolling element 11 rolls along the side surface 12a of the groove portion 12 while sliding between the side surfaces 11f and 12a. Although not shown in detail, when an inertial force having a direction opposite to the above-described inertial force IF is generated on the rolling element 11 and rolls to the other side, the other side surface 11g and the groove portion 12 of the shaft portion 11a are rolled. The rolling element 11 rolls along the other side surface 12b while sliding between the side surfaces 11g and 12b according to the same principle.

FIG. 6 schematically shows another example in which a part of the configuration of the torsional vibration damping device 1 shown in FIG. 1 is changed. As shown in FIG. 6, a rolling surface 14 is formed on the outer peripheral surface 8 of the rolling chamber 10, and a convex portion 16 having a tapered surface is formed near the neutral position on the rolling surface 14. The convex part 16 is formed in a triangular prism shape as an example, and the intersecting line of the tapered two surfaces 16a and 16b is twisted by the angle θ _{1 with} respect to the rotational surface rp of the rotating body 7, that is, intersects with an inclination. . In the example shown in FIG. 6, the rolling element 17 is formed such that the outer diameter in the vicinity of the center is shorter than the outer diameters at both ends in the axial direction of the rolling element 17. That is, the rolling element 17 is formed with tapered inclined surfaces 17a and 17b inclined from both sides in the axial direction toward the center, and a groove portion 18 is formed by these inclined surfaces 17a and 17b. The inclined surfaces 17a and 17b are opposed to the tapered surfaces 16a and 16b of the convex portion 16, respectively. These convex portions 16 and groove portions 18 constitute a guide mechanism 19 in the present invention. In the example shown in FIG. 6, the protrusion 6 is formed in a substantially semicircular shape, and a protrusion symmetric to the protrusion 16, that is, a triangular prism-shaped protrusion is formed on the rolling element 17 side of the protrusion 6. ing. As shown in FIG. 6, the convex portion is provided with tapered surfaces 6 a and 6 b that face the inclined surfaces 17 a and 17 b of the rolling element 17 and fit into grooves formed by the inclined surfaces 17 a and 17 b. In the protrusion 6 shown in FIG. 6, the intersecting line between the tapered two surfaces 6 a and 6 b is inclined with respect to the rotation surface rp of the rotating body 7 by an angle θ ₁ .

  In the torsional vibration damping device 1 having such a configuration, when the inertial force IF is generated in the rolling element 17 to roll to one side and the rolling element 17 is in the vicinity of the neutral position, the convex portion 16 is The groove portion 18 is fitted, and the inclined surface 17a of the rolling element 17 and the tapered surface 16a of the convex portion 16 are in contact with each other. That is, in the place where these surfaces 16a and 17a are in contact, the rolling direction of the rolling element 17 is guided and changed in the direction along the tapered surface 16a. And when it remove | deviates from a neutral position, since the convex part 16 does not fit into the groove part 18, the direction where the rolling element 17 rolls is not guided. That is, when it deviates from the neutral position, the rolling direction of the rolling element 17 may deviate from the direction along the tapered surface 16a. However, when the rolling element 17 returns to the vicinity of the neutral position by the reciprocating motion and the inclined surface 17a and the tapered surface 16a come into contact with each other, the rolling direction of the rolling element 17 is guided in the direction along the tapered surface 16a. Thus, it can be said that the guide mechanism 19 shown in FIG. 6 has a function of adjusting or correcting the rolling direction of the rolling element 17.

Therefore, also in the torsional vibration damping device 1 configured as shown in FIG. 6, the rolling direction of the rolling element 17 is guided by the guide mechanism 19, so even if a plurality of rolling elements 17 are attached to the rotating body 7, The rolling elements 17 can reciprocate on the rolling surface 14 without contacting each other. Further, in the example shown in FIG. 6, compared with the examples shown in FIGS. 1 and 5, the number of places where the convex portion 16 is fitted into the groove 18 is reduced, so that the places where the frictional force f ₂ is generated are reduced. The rolling element 17 can be made to roll easily. Further, in the vicinity of the neutral position, the tapered surfaces 16a and 17a come into contact with each other. Therefore, even if an excessive inertia force is applied, the convex portion 16 is engaged with the groove portion 18 or they are mutually connected. It can be prevented or suppressed from being caught.

Thus, in the torsional vibration damping device 1 according to the present invention, since the rolling elements 11 can roll along the inclination angle θ ₁ , contact between the rolling elements 11 can be prevented or suppressed, Thereby, the desired vibration damping performance can be obtained. Moreover, since the space provided in order to avoid contact between the rolling elements 11 can be reduced, the number of the rolling elements 11 arrange | positioned at the rotary body 7 can be increased. That is, since the total mass of the rolling elements 11 mounted on the apparatus can be increased, the vibration damping performance can be improved.

  DESCRIPTION OF SYMBOLS 1 ... Torsional vibration damping device 11, 17 ... Rolling body 12, 18 ... Groove part, 13, 16 ... Convex part, 14 ... Rolling surface, 15, 19 ... Guide mechanism.

Claims (3)

A rolling surface having a center of curvature is formed on the rotating body at a location deviating from the rotational center of the rotating body, and is brought into contact with the rolling surface by centrifugal force generated by rotating together with the rotating body and torsion of the rotating body. In the torsional vibration damping device including a plurality of rolling elements that roll on the rolling surface by vibration,
When the rolling elements roll on the rolling surface by the torsional vibration, the rolling elements are twisted with respect to the circumferential direction of the rotating body so that the rolling elements do not contact each other. A torsional vibration damping device comprising a guide mechanism for rolling the shaft. The guide mechanism includes a convex portion provided on one of the outer peripheral edge of the rolling element and the rolling surface, and a guide groove provided on the other and fitted to the convex portion. The torsional vibration damping device according to claim 1. The convex part is formed with a tapered inclined surface,
The torsional vibration damping device according to claim 2, wherein a surface facing the tapered surface is formed in the guide groove.

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