WO2017038202A1 - Phase adjustment unit and valve timing changing device - Google Patents

Abstract

This phase adjustment unit includes: a drive-side ring (22); a driven-side ring (31); multiple spherical bodies (40) that make contact with the drive-side ring with a first radius of rotation (R1), make contact with the driven-side ring with a second radius of rotation (R2) different from the first radius of rotation, and are pressed and sandwiched between the drive-side ring and the driven-side ring in at least the axial line direction (S); and an adjustment member (50) capable of adjusting the revolution of the multiple spherical bodies. Thus, it is possible to achieve a simpler structure, a reduction in the number of parts, a reduction in the size of the device, more flexibility in machining precision, and the like.

Description

Phase adjustment unit and valve timing changing device

The present invention relates to a phase adjusting unit that adjusts the relative rotational phase of two rotating bodies, and also uses the phase adjusting unit to change the opening / closing timing (valve timing) of an intake valve or an exhaust valve of an internal combustion engine in accordance with the operating situation. The present invention relates to a valve timing changing device that changes the timing.

Conventional valve timing changing devices include a driving side rotating body including a sprocket that rotates in synchronization with an engine crankshaft, a driven side rotating body that rotates integrally with a camshaft, and a driven side relative to the rotation of the driving side rotating body. What is provided with the phase adjustment unit etc. which adjust the phase of rotation of a rotary body is known (for example, refer patent document 1 etc.).

Here, as the phase adjustment unit, a ring roller that rotates integrally with the driving-side rotator, a sun roller disposed inside the ring roller, and a rotation between the inner peripheral surface of the ring roller and the outer peripheral surface of the sun roller. A planetary traction drive including a plurality of moving planetary rollers, a planetary roller that supports the planetary roller so as to rotate and revolve, and includes a carrier that rotates integrally with the driven-side rotating body as the planetary roller revolves is adopted.
The sun roller of the planetary traction drive is appropriately rotated by an electric motor to change the opening / closing timing of the intake valve or exhaust valve driven by the camshaft.

However, since the phase adjusting unit of the valve timing changing apparatus employs a planetary roller that is long in the axial direction (thrust direction) of the camshaft, the axial dimension becomes long, resulting in an increase in the size of the apparatus. . Further, since the planetary roller and the ring roller, and the planetary roller and the sun roller are in line contact, each roller is required to have strict processing accuracy. Furthermore, a carrier that supports a plurality of planetary rollers so as to rotate and revolve is required, and it is difficult to reduce the number of components structurally.

Also, since the planetary traction drive is a general planetary deceleration mechanism, the reduction ratio cannot be increased so much. Therefore, for example, when the sun roller is rotated using an electric motor when adjusting the phase, an electric motor having a large output is required.

Furthermore, when a planetary roller having a truncated cone shape or a columnar shape that is long in the axial direction is used, there is a risk that problems such as tilting of the rotating shaft of the planetary roller or popping out of the planetary roller may occur during power transmission. Therefore, to prevent these problems, it is necessary to employ a solid carrier.

JP 2010-77814 A

The present invention has been made in view of the above circumstances, and its object is to simplify the structure, reduce the number of parts, reduce the size of the apparatus, reduce the processing accuracy of various parts, and accompanying it. While reducing the manufacturing cost, etc., it is possible to eliminate the tilt and pop-out of the rotation shaft of the rollers that make up the traction drive as in the past, and to increase the reduction ratio and adjust the phase with a small output electric motor, etc. It is an object to provide a phase adjustment unit capable of performing the above and a valve timing changing device including the phase adjustment unit.

The phase adjustment unit of the present invention is a phase adjustment unit that adjusts the relative rotational phase of a driving side rotating body and a driven side rotating body that rotate about a predetermined axis, and is a driving side formed on the driving side rotating body. A ring, a driven ring formed on the driven rotating body, and a contact with the driven ring at a second rotating radius different from the first rotating radius at a first rotating radius around the axis. However, it includes a rotation transmission body that is pressed and clamped between the driving ring and the driven ring at least in the axial direction, and an adjustment member that can rotate and adjust the rotation transmission body.

According to this configuration, in a normal operation in which phase adjustment is not performed, when the driving side rotating body rotates in one direction, the driving side ring rotates integrally with the driving side rotating body. The driven ring rotates in one direction together with the driving side ring via the rotation transmitting body pressed and clamped at least in the axial direction by the driving side ring and the driven side ring.
On the other hand, at the time of phase adjustment, if the adjusting member is appropriately rotated in one direction or the other direction around the axis by a driving source such as an electric motor, the rotation transmission body rotates and is relative to the driving side ring and the driven side ring. A rotational force is exerted while giving a rotational phase difference.
That is, the rotation transmitting body is in contact with the driving side ring at the first turning radius and is in contact with the driven side ring at the second turning radius, so that the driving side ring and the driven side ring are connected to the contact point. A rotation difference corresponding to the difference in rotation radius (difference in contact position) occurs. As a result, a relative rotational phase difference is provided between the driving side ring and the driven side ring, and the phase of the rotation of the driving side rotating body and the rotation of the driven side rotating body is appropriately adjusted.

As described above, the phase adjustment unit includes the drive transmission ring, the driven ring, the rotation transmission body that is pressed and clamped at least in the axial direction while being in contact with the rotation radius different from that of the drive ring and the driven ring, and the adjustment member. Since the differential frictional transmission mechanism is employed, there are no problems such as noise due to backlash that occurs in the case of the gear transmission mechanism and a decrease in durability.
Here, since the rotation transmission body is required to be pressed and clamped in at least the axial direction (thrust direction), not in the direction perpendicular to the axis (radial direction), it can be surely pressed and clamped in the thrust direction to generate a frictional force. As long as the axial dimension can be reduced. Therefore, simplification of the structure, reduction in the number of parts, miniaturization of the apparatus, and the like can be achieved. In addition, problems such as tilting and popping of the rotation shaft of the rotation transmitting body can be solved. Furthermore, since the reduction ratio can be set large, an electric motor having a small output can be used when adjusting the rotation of the adjusting member.

In the phase adjustment unit configured as described above, the rotation transmitting body includes a plurality of spheres arranged around the axis, and the adjustment member can roll the plurality of spheres in cooperation with the driving side ring and the driven side ring. The driving side ring is in contact with the plurality of spheres such that the normal at the contact point with each of the plurality of spheres forms a first angle with respect to the axis, and the driven side ring is in each of the plurality of spheres. A configuration may be adopted in which the normal line at the contact point with the sphere contacts a plurality of spheres so as to form a second angle different from the first angle with respect to the axis.

According to this configuration, in the operation of adjusting the phase, when the adjustment member is appropriately rotated in one direction or the other direction around the axis by a driving source such as an electric motor, the plurality of spheres rotate and revolve respectively. A rotational force is exerted while giving a relative rotational phase difference to the drive side ring and the driven side ring.
Here, since each of the plurality of spheres is in contact with the driving side ring at the first angle and is in contact with the driven side ring at the second angle, the driving side ring and the driven side ring have contact points up to the contact point. Difference in rotation radius (| first rotation radius−second rotation radius |). As a result, a relative rotational phase difference is provided between the driving side ring and the driven side ring, and the phase of the rotation of the driving side rotating body and the rotation of the driven side rotating body is appropriately adjusted.

Here, by using a spherical body as the rotation transmitting body, it is possible to easily form a point contact between the driving side ring and the driven side ring and the spherical body while reducing the dimension in the axial direction. In particular, it is possible to eliminate the tilt of the rotating shaft and the protrusion of the roller that occur in the case of a roller that is long in the axial direction as in the prior art.
Further, for example, a spherical body can be easily obtained by diverting a general-purpose product such as a steel ball applied to a bearing or the like, so that strict processing accuracy as in the prior art is not required, and the manufacturing cost can be reduced.
Further, since the driving side ring and the driven side ring are in contact with the sphere at the first angle and the second angle, respectively, the driving side ring and the driven side ring are not only pushed in the thrust direction but also in the radial direction with respect to the sphere. A pressure is exerted, and the spherical body can be surely pressed and clamped in cooperation with the adjusting member to obtain a desired frictional force.

In the phase adjustment unit configured as described above, the adjustment member is disposed on the inner side of the plurality of spheres in the radial direction perpendicular to the axis, and the driving side ring and the driven side ring are formed from the plurality of spheres in the radial direction perpendicular to the axis. Alternatively, a configuration may be adopted that is arranged outside.
According to this configuration, since the adjustment member → the plurality of spheres → the driving side ring and the driven side ring are arranged from the side close to the axis toward the outside in the radial direction, for example, the housing formed integrally with the sprocket As described above, the phase adjustment units can be collectively arranged within a range that does not exceed the outer diameter of the driving side rotating body. Therefore, downsizing of the device in the radial direction perpendicular to the axis can be achieved.

In the phase adjustment unit having the above-described configuration, the adjustment member may have a V-groove having a substantially V-shaped cross section so as to contact each of the plurality of spheres at two points.
According to this configuration, the plurality of spheres can be easily positioned in the axial direction in cooperation with the drive side ring and the driven side ring by fitting the plurality of spheres into the V groove of the adjustment member. In addition, by positioning each sphere at two points of the V-groove, it is possible to prevent each sphere from rotating vertically (that is, rotating in an undesired direction) as compared with the case of positioning at one point.

The phase adjustment unit having the above-described configuration may employ a configuration further including a pressing application mechanism that applies a pressing force in the axial direction between the driving side rotating body and the driven side rotating body and the rotation transmitting body.
According to this configuration, since the rotation transmitting body is pressed and clamped by the driving side ring and the driven side ring, even if a change with time occurs in the pressing force, the pressing force is applied by the pressing mechanism. A desired pressing force can be obtained by compensating for the change with time. In particular, when a disc spring or the like is used as the pressing mechanism, a predetermined pressing force can be generated even when the engine is stopped. When a loading cam mechanism or the like is used, the pressing according to the torque is started at the start of the engine. Pressure can be generated.

The phase adjustment unit having the above-described configuration may employ a configuration that further includes a retainer that positions the plurality of spheres at predetermined intervals.
According to this configuration, since the plurality of spheres are maintained at a predetermined interval by the retainer, it is possible to prevent the plurality of spheres from contacting each other when rotating and revolving. Therefore, a collision between a plurality of spheres can be prevented, and the plurality of spheres can perform stable rotation and revolution.

In the phase adjustment unit having the above-described configuration, a configuration in which the first rotation radius is set smaller than the second rotation radius may be adopted.
According to this configuration, at the time of phase adjustment, the adjusting member is rotated faster or slower (braking) in the same direction as the driving side ring and the driven side ring, and much energy is required to rotate faster. And
For example, when the phase adjustment unit is applied when adjusting the opening / closing timing of the intake valve or exhaust valve of the engine, the phase adjustment direction has an advance angle direction and a retard angle direction, and the advance angle direction is the intake valve or exhaust valve direction. Since it is the direction to push the valve open, it requires more energy than the retarding direction. Here, by setting the first turning radius <the second turning radius (that is, the first angle <the second angle), it is possible to advance the angle when the brake is applied to the adjusting member, and to save energy. Can do.

The valve timing changing device according to the present invention includes a phase adjustment unit that adjusts the relative rotation phase of a driving side rotating body that rotates in conjunction with rotation of a crankshaft and a driven side rotating body that rotates integrally with a camshaft. A valve timing changing device that changes the opening / closing timing of an intake valve or an exhaust valve driven by a camshaft, and employs any one of the phase change units configured as described above as a phase change unit.

According to this configuration, during normal operation without phase adjustment, when the driving side rotating body rotates in one direction in conjunction with the crankshaft, the driving side ring rotates integrally with the driving side rotating body, The driven ring rotates in one direction together with the driving ring via the rotation transmission body, and the camshaft rotates in one direction integrally with the driven ring. By the rotation of the camshaft, the intake valve or the exhaust valve is opened / closed at a predetermined valve timing.
On the other hand, at the time of phase adjustment, if the adjusting member is appropriately rotated in one direction or the other direction around the axis line by a driving source such as an electric motor, the rotation transmission body rotates to cause a phase difference between the driving side ring and the driven side ring. Applying rotational force while giving

That is, since the rotation transmitting body is in contact with the driving side ring at the first turning radius and is in contact with the driven side ring at the second turning radius, the driving side ring and the driven side ring rotate to the contact point. A rotation difference corresponding to the difference in radius (difference in contact position) occurs.
As a result, a relative rotational phase difference is given between the driving side ring and the driven side ring, and the phase of the rotation of the driving side rotating body and the rotation of the driven side rotating body is adjusted as appropriate. The opening and closing time can be changed.

According to the phase adjustment unit configured as described above, the structure is simplified, the number of parts is reduced, the apparatus is downsized, the processing accuracy of various parts is reduced, and the manufacturing cost is reduced accordingly. In addition, problems such as the inclination of the rotating shaft of the roller constituting the traction drive and the protrusion of the roller can be solved, and the reduction ratio can be set large, so that the phase adjustment can be performed with a small output electric motor or the like.

It is a disassembled perspective view which shows one Embodiment of the valve timing change apparatus provided with the phase adjustment unit which concerns on this invention. It is a perspective sectional view which passes along the axis line of the valve timing change apparatus shown in FIG. It is sectional drawing which passes along the axis line of the valve timing change apparatus shown in FIG. While showing the relationship of the drive side ring, driven side ring, rotation transmission body (sphere), and adjustment member which constitute the phase adjustment unit of the present invention, the first rotation radius (and the first angle) is the second rotation radius (and It is a schematic diagram which shows a structure smaller than (2nd angle). While showing the relationship of the drive side ring, driven side ring, rotation transmission body (sphere), and adjustment member which constitute the phase adjustment unit of the present invention, the first rotation radius (and the first angle) is the second rotation radius (and It is a schematic diagram which shows a structure larger than (2nd angle). FIG. 7 is a diagram illustrating the operation of the phase adjustment unit of the present invention, and is a schematic diagram illustrating the operation of the drive side ring, the rotation transmission body (sphere), and the driven side ring in a state where phase adjustment is not performed. FIG. 9 is a diagram illustrating the operation of the phase adjustment unit according to the present invention, and is a schematic diagram illustrating the operation of a drive side ring, a rotation transmission body (sphere), and a driven side ring when performing phase adjustment. It is a schematic diagram for demonstrating the reduction ratio in the phase adjustment unit of this invention. It is a disassembled perspective view which shows other embodiment of the valve timing change apparatus provided with the phase adjustment unit which concerns on this invention. It is a perspective sectional view which passes along the axis line of the valve timing change apparatus shown in FIG. It is sectional drawing which passes along the axis line of the valve timing change apparatus shown in FIG. It is a schematic diagram which shows the arrangement | positioning relationship of the loading cam mechanism as a press addition mechanism contained in the phase adjustment unit of this invention. It is a schematic diagram which shows the arrangement | positioning relationship of the loading cam mechanism as a press addition mechanism contained in the phase adjustment unit of this invention. Among the driving side ring, driven side ring, rotation transmission body (sphere), and adjustment member constituting the phase adjustment unit of the present invention, other embodiments of the adjustment member are shown, and the first rotation radius (and the first angle) are shown. ) Is a schematic diagram showing a configuration in which the second turning radius (and the second angle) is smaller. Among the driving side ring, driven side ring, rotation transmission body (sphere), and adjustment member constituting the phase adjustment unit of the present invention, other embodiments of the adjustment member are shown, and the first rotation radius (and the first angle) are shown. ) Is a schematic diagram showing a configuration in which the second turning radius (and the second angle) is larger.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
As shown in FIGS. 1 to 3, the valve timing changing device according to this embodiment is supported on a drive side that is rotatably supported around an axis S of a camshaft CS in conjunction with rotation of a crankshaft included in an engine. A rotating body A, a driven side rotating body B that rotates integrally with the camshaft CS, a phase adjusting unit that adjusts the relative rotational phase of the driving side rotating body A and the driven side rotating body B, a thrust bearing SB, and the like. Yes.

As shown in FIGS. 1 to 3, the phase adjustment unit includes a drive-side ring 22, a driven-side ring 31, a plurality of spheres 40 as a rotation transmission body, an adjustment member 50, a retainer 60, and a pair of dishes as a pressing addition mechanism. A spring DS or the like is provided.

Then, the adjustment member 50 included in the phase adjustment unit is appropriately rotated and adjusted by an electric motor (not shown) or the like, thereby changing the opening / closing timing (valve timing) of the intake valve or the exhaust valve driven by the camshaft CS. It is like that.

As shown in FIGS. 1 to 3, the drive-side rotator A is connected to the first housing 10 that is rotatably supported around the axis S of the camshaft CS, and is connected to the first housing 10 by a bolt B <b> 1. A second housing 20 and the like are provided.
As shown in FIGS. 2 and 3, the first housing 10 accommodates a sprocket 11 around which a chain for transmitting rotation of the crankshaft is wound, an annular fitting recess 12 into which the thrust bearing SB is fitted, and a pair of disc springs DS. It has an annular housing recess 13, a plurality of screw holes 14 into which the bolts B1 are screwed.
As shown in FIGS. 2 and 3, the second housing 20 has a cylindrical portion 21 that is joined to the first housing 10, a drive side ring 22, a through hole 23 that exposes the adjustment member 50, and a plurality of penetrations through which bolts B1 are passed. It has holes 24 and the like.
As shown in FIGS. 2 to 4B, the drive side ring 22 has a contact surface 22 a that makes point contact with the plurality of spheres 40.
Here, as shown in FIGS. 4A and 4B, the contact surface 22a is formed in a conical surface shape with the axis S as the center, and makes point contact with the plurality of spheres 40, that is, the first rotation radius R1 around the axis S. It is formed so as to make point contact with the sphere 40. Further, the contact surface 22a has a sphere at a position where the normal line at the contact point forms a first angle θ1 with respect to an axis S ′ passing through the center of the sphere 40 and parallel to the axis S (that is, with respect to the axis S). It is formed so as to make point contact with 40.

As shown in FIGS. 1 to 3, the driven-side rotating body B includes a driven-side ring 31 disposed so as to face the driving-side ring 22 in the axis S direction, a fitting cylinder portion 32 fitted into the camshaft CS, The driven disk 30 is integrally formed with a through hole 33 and the like through which the bolt B2 passes.
Then, the driven disk 30 is fastened to the camshaft CS by a bolt B2 so as to rotate about the axis S integrally with the camshaft CS.
As shown in FIGS. 2 to 4B, the driven ring 31 has a contact surface 31 a that makes point contact with the plurality of spheres 40.
Here, as shown in FIGS. 4A and 4B, the contact surface 31a is formed in a conical surface shape with the axis S as the center, and makes point contact with the plurality of spheres 40, that is, the axis S different from the first rotation radius R1. It is formed so as to make point contact with the sphere 40 at a second rotation radius R2. Further, the contact surface 31a has a second angle θ2 that is different from the first angle θ1 with respect to an axis S ′ that passes through the center of the sphere 40 and is parallel to the axis S (that is, with respect to the axis S). It is formed so as to make point contact with the sphere 40 at the position formed.
4A shows a configuration in which the first rotation radius R1 <the second rotation radius R2 and the first angle θ1 <the second angle θ2. FIG. 4B shows a configuration in which the first rotation radius R1> the second rotation radius R2 and the first angle θ1> the second angle θ2. As the phase adjustment unit, any of the configurations shown in FIGS. 4A and 4 may be adopted.

As shown in FIGS. 1 to 3, the plurality of spheres 40 are fitted into the V-groove 51 of the adjustment member 50 so as to be arranged in an annular shape around the axis S so as to be freely rotatable, and in the direction of the axis S The ring 22 and the driven ring 31 are disposed so as to be pressed and clamped.
As shown in FIGS. 4A and 4B, each sphere 40 makes point contact with the contact surface 22a of the drive side ring 22 at the first rotation radius R1 around the axis S, and the normal line at the contact point is the sphere 40. Are arranged so as to form a first angle θ1 with respect to an axis S ′ that passes through the center of the axis and is parallel to the axis S (that is, with respect to the axis S).
Further, each sphere 40 makes point contact with the contact surface 31a of the driven ring 31 at a second rotation radius R2 around the axis S different from the first rotation radius R1, and the normal line at the contact point is that of the sphere 40. It is arranged so as to form a second angle θ2 with respect to an axis S ′ passing through the center and parallel to the axis S (that is, with respect to the axis S).
Further, each sphere 40 is in two-point contact with the contact surface 51a of the V groove 51 of the adjustment member 50 at the third rotation radius R3 around the axis S.

In a normal operation state in which the valve timing is not adjusted, the plurality of spheres 40 have a role of locking and rotating the driving side ring 22 and the driven side ring 31 by friction force without rotating. Eggplant.
On the other hand, when adjusting the valve timing, the plurality of spheres 40 are rotated and revolved appropriately through the rotation adjustment of the adjustment member 50, so that the rotational radius of the drive side ring 22 and the driven side ring 31 is increased. A rotation difference corresponding to the difference (| R1−R2 |) is generated, and a relative rotation phase difference is provided between the rotation of the driving side rotating body A and the rotation of the driven side rotating body B.

The adjustment member 50 is formed to be rotatable about the axis S as shown in FIGS. 1 to 4B.
The adjusting member 50 removably connects a drive shaft (not shown) such as an electric motor or the like having a substantially V-shaped cross section so as to contact the plurality of spheres 40 at two points in the axis S direction. The connection part 52 grade | etc., Is provided.
The adjustment member 50 is configured to press and hold the sphere 40 from the axis S direction between the driving side ring 22 and the driven side ring 31 in a state where the plurality of spheres 40 held by the retainer 60 are fitted in the V-groove 51. By connecting the first housing 10 and the second housing 20, at least the connecting portion 52 is assembled from the through hole 23 so as to be rotatable around the axis S.
Here, as shown in FIGS. 4A and 4B, the contact surface 51a of the V-groove 51 is in contact at two points aligned in the axis S direction at the third rotation radius R3 around the axis S, and the axis of the sphere 40 The spherical body 40 is pressed and supported so as to be able to roll in cooperation with the contact surface 22a of the drive side ring 22 and the contact surface 31a of the driven side ring 31 while restricting the displacement in the S direction.

As shown in FIG. 1, the retainer 60 is formed in a cylindrical shape, and receives each of the spheres 40 so that the spheres 40 can roll with a predetermined gap, and the plurality of spheres 40 are spaced apart from each other around the axis S. A plurality of circular holes 61 are provided.
According to this, since the plurality of spheres 40 are maintained at a predetermined interval around the axis S by the retainer 60, the plurality of spheres 40 can be prevented from contacting each other when rotating and revolving. Therefore, the plurality of spheres 40 can be prevented from colliding with each other, and the plurality of spheres 40 can be stably rotated and revolved.
In the phase adjustment unit, the retainer 60 is not essential, and a configuration in which the retainer 60 is eliminated may be employed.

The pair of disc springs DS is disposed in the housing recess 13 of the first housing 10 as shown in FIGS. 1 to 3. The pair of disc springs DS exert a pressing force that separates the first housing 10 and the driven disk 30 from each other in the axis S direction. That is, the pair of disc springs DS serves as a pressing mechanism that applies a pressing force in the direction of the axis S between the driving ring 22 and the driven ring 31 and the sphere 40.
According to this, even when the pressing force is changed with time in a state where the spherical body 40 is pressed and clamped by the driving side ring 22 and the driven side ring 31, the pressing force is applied by the pair of disc springs DS. Therefore, a desired pressing force can be obtained by compensating for the change with time, and in particular, a predetermined pressing force can be generated even when the engine is stopped.

In the above configuration, the driving side ring 22 included in the driving side rotating body A, the driven side ring 31 included in the driven side rotating body B, and the driving side ring 22 are in contact with each other at the first rotation radius R1 around the axis S. A plurality of spheres 40 as rotation transmission bodies that are pressed and clamped between the driving side ring 22 and the driven side ring 31 at least in the direction of the axis S while being in contact with the driven side ring 31 at a second rotation radius R2 different from the first rotation radius R1. The phase adjusting unit that adjusts the phase of rotation of the driven side rotating body B with respect to the rotation of the driving side rotating body A is configured by the adjusting member 50 that can adjust the rotation (spinning and revolution) of the plurality of spheres 40 about the axis S. ing.

The operation of this phase adjustment unit will be described.
First, when the valve timing is not changed, as shown in FIG. 5A, when the driving side rotating body A including the driving side ring 22 rotates in one direction, the driven side ring 31 is moved through the frictional force of the plurality of spheres 40. The driven-side rotating body B and the adjustment member 50 that are included also rotate integrally in one direction.
On the other hand, when changing the valve timing, as shown in FIG. 5B, when the adjusting member 50 is rotated in one direction or the other direction using an electric motor (not shown) or the like, the plurality of spheres 40 rotate. And revolves around the axis S to generate a rotation difference corresponding to the difference in rotation radius (| first rotation radius R1−second rotation radius R2 |) between the drive side ring 22 and the driven side ring 31 to drive A relative rotational phase difference is generated between the rotation of the side rotating body A and the rotation of the driven side rotating body B.
Therefore, it can be changed to a desired valve timing by appropriately adjusting the rotation of the adjusting member 50.

According to the phase adjustment unit having the above-described configuration, it is possible to simplify the structure, reduce the number of parts, reduce the size of the apparatus, and the like. In particular, by using the spherical body 40 as the rotation transmitting body, it is possible to easily form a point contact between the driving side ring 22 and the driven side ring 31 and the spherical body 40 while reducing the dimension in the axis S direction. Therefore, it is possible to solve problems such as tilting of the rotating shaft and popping out of the roller that occur when using a roller that is long in the axial direction as in the prior art.
Further, for example, by diverting a steel ball or the like applied to a bearing or the like, the sphere 40 can be easily obtained, and the strict processing accuracy as in the prior art is not required, and the manufacturing cost can be reduced.
Furthermore, since the driving side ring 22 and the driven side ring 31 are in contact with the spherical body 40 at the first angle θ1 and the second angle θ2, respectively, the driving side ring 22 and the driven side ring 31 are thrust against the spherical body 40. The pressing force is applied not only in the direction (axis S direction) but also in the radial direction. Thereby, in cooperation with the adjustment member 50, the spherical body 40 can be reliably pressed and clamped to obtain a desired frictional force.

The reduction ratio of the position adjustment unit having the above configuration will be described with reference to FIG.
In addition to the first rotation radius R1, the second rotation radius R2, and the third rotation radius R3, the rotation radius from the center of the sphere 40 to the contact point of the drive side ring 22 is Rb1, and the center of the sphere 40 is moved to the driven ring 31. When the rotation radius to the contact point is Rb2, and the rotation radius from the center of the sphere 40 to the contact point of the adjustment member 50 is Rb3, the reduction ratio α is expressed by the following equation.
α = − {R2 · (Rb3 · R1 + Rb1 · R3)} / {R3 · (Rb2 · R1−Rb1 · R2)}
Therefore, by setting the values of R1 and R2 (values of Rb1 and Rb2) to different values, the high reduction ratio can be easily set.
By setting the reduction ratio α to be large, the adjustment member 50 can be rotationally adjusted with a small output electric motor or the like, which contributes to power saving, miniaturization of the electric motor, and the like.

In the position adjustment unit configured as described above, the adjustment member 50 is disposed inside the sphere 40 in the radial direction perpendicular to the axis S, and the driving side ring 22 and the driven side ring 31 are spherical in the radial direction perpendicular to the axis S. 40, the adjustment member 50 → the sphere 40 → the drive side ring 22 and the driven side ring 31 are arranged from the side close to the axis S of the camshaft CS toward the outside in the radial direction. become.
Therefore, the phase adjustment units can be arranged in a concentrated manner within a range not exceeding the outer diameter of the housing 10 formed integrally with the drive side rotor A, for example, the sprocket 11, and the diameter perpendicular to the axis S A reduction in the size of the device in the direction can be achieved.

In the phase adjustment unit configured as described above, it is preferable that the first rotation radius R1 is set smaller than the second rotation radius R2.
At the time of phase adjustment, the adjustment member 50 is rotated faster or slower (a brake is applied) in the same direction as the driving side ring 22 and the driven side ring 31, and much energy is required to rotate the adjustment member 50 faster. The direction of phase adjustment includes an advance angle direction and a retard angle direction. Since the advance direction is a direction in which the intake valve or the exhaust valve is pushed open, it requires more energy than the retard direction.
Here, by setting the first turning radius R1 <the second turning radius R2 (that is, the first angle θ1 <the second angle θ2), the adjustment member 50 can be advanced when the brake is applied, and the energy Labor saving can be achieved.

In the phase adjustment unit having the above configuration, it is preferable to set the first angle θ1 and the second angle θ2 to be larger than 45 degrees.
According to this, when variations occur in the processing of the contact surfaces 22a, 31a of the drive side ring 22 and the driven side ring 31, variations occur in the rotation radii R1, R2 at the contact position with the sphere 40, that is, at the contact points. Although there is a possibility of affecting the reduction ratio, by setting the first angle θ1> 45 degrees and the second angle θ2> 45 degrees, it is possible to suppress the variation in the rotation radius due to the processing variation of the contact surfaces 22a and 31a. it can.
Further, by setting the first angle θ1> 45 degrees and the second angle θ2> 45 degrees, the first rotation radius R1 and the second rotation radius R2 can be set to large values, and a large torque can be transmitted.
Further, by setting the first angle θ1> 45 degrees and the second angle θ2> 45 degrees, the axial line is generated based on the generation of the normal force due to the wedge effect of the contact surfaces 22 and 31a of the driving side ring 22 and the driven side ring 31. The pressing force generated in the S direction can be increased.

7 to 9 show another embodiment of the valve timing changing device according to the present invention. The embodiment described above except that one disc spring DS and a loading cam mechanism RC are employed as the pressing addition mechanism. The same components are denoted by the same reference numerals and description thereof is omitted.
As shown in FIGS. 7 to 9, the valve timing changing device according to this embodiment includes a first housing 10 ′ and a second housing 20 constituting the driving side rotating body A, and a driven side constituting the driven side rotating body B. Disks 30 'and 70, a phase adjustment unit, a thrust bearing SB, a bearing disk 80, and the like are provided.
The phase adjustment unit includes a drive side ring 22, a driven side ring 31, a plurality of spheres 40, an adjustment member 50, a retainer 60, a single disc spring DS as a pressing addition mechanism, a loading cam mechanism RC, and the like.

As shown in FIGS. 8 and 9, the first housing 10 ′ includes a sprocket 11, one disc spring DS, an annular fitting recess 12 ′ into which a thrust bearing SB incorporated in the bearing disk 80 is fitted, and a driven disk. An annular housing recess 13 ′ for housing 70, a plurality of screw holes 14, and the like.
As shown in FIGS. 7 to 9, the driven disk 30 ′ includes a driven ring 31, a cam portion 32 ′ that defines a cam groove that exerts a cam action on the sphere 74, a through hole 33, and the like.
As shown in FIGS. 7 to 9, the driven-side disk 70 is disposed so as to be opposed to the cam portion 32 'and defines a cam groove or the like that exerts a cam action on the sphere 74, and is fitted into the camshaft CS. It has a joint tube portion 72, a through hole 73 through which the bolt B2 is passed.

The loading cam mechanism RC is constituted by the cam portion 32 ′, the cam portion 71, and the plurality of spheres 74. When the driven disk 30 ′ and the driven disk 70 rotate about the axis S, the loading cam mechanism RC causes the sphere 74 to receive the cam action when the torque fluctuation or rotational phase shift occurs. A pressing force is generated so that the disk 30 ′ and the driven disk 70 are separated from each other in the axis S direction. As a result, the loading cam mechanism RC applies a pressing force in the direction of the axis S between the driving side ring 22 and the driven side ring 31 and the sphere 40.

According to the apparatus having the above configuration, by adopting the single disc spring DS and the loading cam mechanism RC as the pressing addition mechanism, the spherical body 40 is pressed and clamped by the driving side ring 22 and the driven side ring 31. Even if a change with time occurs in the pressing force, a desired pressing force can be obtained by compensating the change with time. In particular, it is possible to generate a predetermined pressing force even when the engine is stopped by one disc spring DS, and it is possible to generate a pressing force corresponding to the torque at the start of the engine by the loading cam mechanism RC.

According to the apparatus according to this embodiment, as in the above-described embodiment, the phase adjustment unit is in contact with the driving side ring 22, the driven side ring 31, the driving side ring 22, and the driven side ring 31 at a different radius of rotation. Since the differential friction transmission mechanism including the spherical body 40 pressed and clamped at least in the direction of the axis S and the adjustment member 50 is employed, problems such as noise due to backlash generated in the case of the gear transmission mechanism and a decrease in durability occur. There is nothing.
In addition, since the spherical body 40 is required to be pressed and clamped at least in the direction of the axis S (thrust direction) rather than in the direction perpendicular to the axis S (radial direction), it can be surely pressed and clamped in the thrust direction to generate a frictional force. As long as the dimension in the axis S direction can be reduced, the structure can be simplified, the number of parts can be reduced, and the apparatus can be downsized.
Furthermore, since the reduction ratio can be set large, an electric motor having a small output can be used when adjusting the rotation of the adjusting member 50.

Here, regarding the arrangement relationship between the loading cam mechanism RC and the thrust bearing SB, as shown in FIG. 10A, the arrangement relationship in the embodiment of FIGS. 7 to 9 or as shown in FIG. 10B, the thrust bearing SB An arrangement relationship in which the loading cam mechanism RC is replaced may be employed.

FIG. 11A and FIG. 11B are schematic views showing another embodiment of the adjusting member included in the valve timing changing device according to the present invention. As shown in FIGS. 11A and 11B, the adjustment member 50 ′ includes a contact surface 51 a defined by the outer peripheral surface of the cylindrical portion 51 ′ so as to contact the plurality of spheres 40 at one point.
And adjustment member 50 'arranges the some spherical body 40 hold | maintained by the retainer 60 so that it may roll on the contact surface 51a. Further, the first housing 10 and the second housing 20 are connected while the spherical body 40 is pressed and clamped from the axis S direction by the driving side ring 22 and the driven side ring 31, so that the adjustment member 50 ′ In cooperation with the contact surface 22a and the contact surface 31a of the driven-side ring 31, the plurality of spheres 40 are pressed and supported so as to roll freely.

That is, each sphere 40 makes point contact with the contact surface 22a of the drive side ring 22 at the first rotation radius R1 around the axis S, as shown in FIGS. 11A and 11B, and the normal line at the contact point is It arrange | positions so that the 1st angle (theta) 1 may be made | formed with respect to the axis line S 'which passes along the center of the spherical body 40 and is parallel to the axis line S (namely, with respect to the axis line S).
Further, each sphere 40 makes point contact with the contact surface 31a of the driven ring 31 at a second rotation radius R2 around the axis S different from the first rotation radius R1, and the normal line at the contact point is that of the sphere 40. It is arranged so as to form a second angle θ2 with respect to an axis S ′ passing through the center and parallel to the axis S (that is, with respect to the axis S).
Further, each sphere 40 is in contact with the contact surface 51 a ′ of the cylindrical portion 51 ′ of the adjustment member 50 ′ at a single point at the third rotation radius R 3 ′ around the axis S.

The operation of the adjustment member 50 'is the same as described above.
That is, when the valve timing is not changed, when the driving side rotating body A including the driving side ring 22 rotates in one direction, the driven side rotating body B including the driven side ring 31 and the frictional force of the plurality of spherical bodies 40 and The adjustment member 50 'also rotates integrally in one direction.
On the other hand, when changing the valve timing, when the adjusting member 50 ′ is rotated in one direction or the other direction using an electric motor (not shown) or the like, the plurality of spheres 40 rotate and revolve around the axis S. Thus, a rotation difference corresponding to the difference in rotation radius (| first rotation radius R1−second rotation radius R2 |) is generated between the driving side ring 22 and the driven side ring 31 to rotate the driving side rotating body A. And a relative phase difference is caused between the rotation of the driven-side rotator B.

As described above, according to the valve timing changing device configured as described above, the phase adjustment unit is in contact with the driving side ring 22, the driven side ring 31, the driving side ring 22, and the driven side ring 31 at a different rotation radius. However, since a differential friction transmission mechanism including a rotation transmission body (sphere 40) pressed and clamped at least in the direction of the axis S and the adjustment members 50 and 50 ′ is employed, noise due to backlash generated in the case of the gear transmission mechanism, There is no problem such as a decrease in durability.

Further, since the rotation transmitting body (sphere 40) is required to be pressed and clamped in at least the direction of the axis S (thrust direction), not in the direction perpendicular to the axis S (radial direction), it is reliably pressed and clamped in the thrust direction. As long as force can be generated, the dimension in the direction of the axis S can be reduced, and the structure can be simplified, the number of parts can be reduced, and the apparatus can be downsized.
Further, there is no problem such as tilting or jumping out of the rotation axis of the rotation transmitting body (sphere 40). Furthermore, since the reduction ratio can be set large, an electric motor having a small output can be used when adjusting the rotation of the adjusting members 50 and 50 '.

In the above embodiment, the case where the sphere 40 is adopted as the rotation transmission body constituting the phase adjustment unit is shown, but the present invention is not limited to this. At least in the direction of the axis S and the movement of the driving-side ring and the movement of the driving-side ring at the first turning radius R1 around the axis A and at the second turning radius R2 different from the first turning radius R1. As long as the rotation transmission body is pressed and clamped by the side ring, a rotation transmission body in another form may be adopted.

As described above, the phase adjustment unit of the present invention achieves the simplification of the structure, the reduction of the number of parts, the downsizing of the apparatus, the reduction of processing accuracy of various parts, the reduction of the manufacturing cost associated therewith, and the like. It is possible to eliminate the inclination and pop-out of the rotating shaft of the roller constituting the conventional traction drive, and to increase the reduction ratio and adjust the phase with an electric motor with a small output. Therefore, this phase adjustment unit can be applied as a valve timing changing device for an internal combustion engine, and is also useful for mechanisms and devices that need to adjust the relative rotational phase of two rotating bodies.

CS Camshaft S Axis A Drive side rotator B Driven side rotator SB Thrust bearing DS Disc spring (Pressurizing mechanism)
RC loading cam mechanism (pressing mechanism)
B1, B2 Bolts 10, 10 'First housing 11 Sprocket 12, 12' Fitting recess 13, 13 'Housing recess 14 Screw hole 20 Second housing 21 Cylindrical portion 22 Drive side ring (phase adjustment unit)
22a Contact surface 23, 24 Through hole 30, 30 'Drive side disk 31 Drive side ring (phase adjustment unit)
31a Contact surface 32 Fitting cylinder part 32 'Cam part (loading cam mechanism)
33 Through-hole 40 Sphere (Rotation transmission body, phase adjustment unit)
50, 50 'adjustment member (phase adjustment unit)
51 V-groove 51 ′ Cylindrical portions 51 a, 51 a ′ Contact surface 52 Connecting portion 60 Retainer 70 Driven disk 71 Cam portion (loading cam mechanism)
72 fitting cylinder 73 through-hole 74 sphere (loading cam mechanism)
80 Bearing disc R1 First turning radius R2 Second turning radius θ1 First angle θ2 Second angle

Claims (8)

1. A phase adjusting unit for adjusting a relative rotational phase of a driving side rotating body and a driven side rotating body that rotate around a predetermined axis;
   A drive side ring formed on the drive side rotating body;
   A driven ring formed on the driven rotating body;
   At least in the axial direction, in contact with the driven ring at a first turning radius around the axis and in contact with the driven ring at a second turning radius different from the first turning radius; A rotation transmission body pressed and held by the driven ring;
   An adjustment member capable of rotationally adjusting the rotation transmission body;
   Including a phase adjustment unit.
2. The rotation transmission body includes a plurality of spheres arranged around the axis,
   The adjusting member supports the plurality of spheres so as to roll in cooperation with the driving side ring and the driven side ring,
   The driving ring is in contact with the plurality of spheres such that a normal line at a contact point with each of the plurality of spheres forms a first angle with respect to the axis;
   The driven ring contacts the plurality of spheres such that a normal line at a contact point with each of the plurality of spheres forms a second angle different from the first angle with respect to the axis;
   The phase adjustment unit according to claim 1.
3. The adjustment member is disposed inside the plurality of spheres in a radial direction perpendicular to the axis,
   The drive side ring and the driven side ring are disposed outside the plurality of spheres in a radial direction perpendicular to the axis.
   The phase adjustment unit according to claim 2.
4. The adjusting member has a V-groove having a substantially V-shaped cross section so as to contact each of the plurality of spheres at two points.
   The phase adjustment unit according to claim 2, wherein the phase adjustment unit is provided.
5. A pressure applying mechanism for applying a pressing force in the axial direction between the driving side rotating body and the driven side rotating body and the rotation transmitting body;
   The phase adjustment unit according to claim 2, wherein the phase adjustment unit is a unit.
6. A retainer for positioning the plurality of spheres at a predetermined distance from each other;
   6. The phase adjustment unit according to claim 2, wherein
7. The first turning radius is set smaller than the second turning radius;
   The phase adjustment unit according to claim 1, wherein the phase adjustment unit is a unit.
8. A phase adjusting unit for adjusting a relative rotational phase between a driving side rotating body that rotates in conjunction with rotation of the crankshaft and a driven side rotating body that rotates integrally with the camshaft, and is driven by the camshaft; A valve timing changing device for changing the opening / closing timing of an intake valve or an exhaust valve,
   The phase adjustment unit is the phase adjustment unit according to any one of claims 1 to 7.
   A valve timing changing device characterized by that.
   

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