JP7040283B2 - Valve opening / closing timing control device - Google Patents

Description

The present invention relates to a valve opening / closing timing control device that sets a relative rotation phase between a driving side rotating body and a driven side rotating body by a driving force of an electric actuator.

Conventionally, for opening and closing valves of an internal combustion engine in a state where the drive side rotating body that rotates synchronously with the crankshaft of the internal combustion engine centering on the rotating shaft core and the drive side rotating body are arranged radially inside the driving side rotating body with a coaxial core with the rotating shaft core. A valve opening / closing timing control device including a driven side rotating body that rotates integrally with the camshaft of the above and an electric actuator that sets the relative rotation phase of the driving side rotating body and the driven side rotating body is known (for example, a patent). See Document 1).

The valve open / close timing control device described in Patent Document 1 is connected to an output gear (a driven side internal gear portion in the document) provided on the driven side rotating body and a driving side rotating body, and is eccentric with respect to the rotating shaft core. An input gear that rotates on an eccentric shaft (planetary gear in the literature), a tubular eccentric member that supports the input gear (planetary carrier in the literature), and the radial inside of the driven side rotating body and the diameter of the eccentric member. A first bearing (planetary bearing in the literature) placed between the outside of the direction and a second bearing (planetary in the literature) placed between the radial inside of the drive-side rotating body and the radial outside of the eccentric member. (Bearing) and (see FIGS. 19 to 21 of Patent Document 1). Further, the input gear is connected to the drive-side rotating body by a drive-side external gear portion that meshes with the drive-side internal gear portion formed on the drive-side rotating body, and further extends between the first bearing and the driven-side rotating body. It has a driven side external gear that meshes with the output gear of the extended driven side rotating body.

The first bearing is urged in the direction of the input gear by a spring member, and has a drive-side internal gear portion of the drive-side rotating body and a drive-side external gear portion of the input gear having fewer teeth than the drive-side internal gear portion. Are meshed with each other, and the output gear of the driven side rotating body and the driven side external gear portion of the input gear having fewer teeth than the driven side internal gear portion are meshed with each other. Further, the driven side external gear portion of the input gear is formed to have a smaller number of teeth than the drive side external gear portion, and the eccentric shaft core is revolved around the rotating shaft core by the rotation of the eccentric member by the driving force of the electric actuator. The meshing position between the drive side external gear portion and the driven side external gear portion of the input gear and the drive side internal gear portion and the output gear of the driven side rotating body is changed. As a result, the relative rotation phase is changed by the difference in the number of teeth between the driven side external gear portion and the driving side external gear portion in the input gear.

Japanese Unexamined Patent Publication No. 2008-38886

The valve open / close timing control device described in Patent Document 1 urges the first bearing with a spring member to eliminate backlash in the meshing portion between the input gear and the output gear. The spring member and the second bearing are eliminated. It is necessary to design so that it does not come into contact with the bearing. In the technique described in Patent Document 1, a protrusion is provided on the radial outer side of the eccentric member, and the protrusion is arranged between the spring member and the second bearing so that the spring member and the second bearing are in sliding contact with each other. Is prevented.

However, the valve opening / closing timing control device described in Patent Document 1 can shorten the distance in the rotation axis direction between the first bearing and the second bearing urged by the spring member by the protrusion of the eccentric member. However, the shaft length becomes large. Moreover, as the distance between the first bearing and the second bearing increases, the moment applied to these bearings increases due to the reaction force received from the meshing portion between the output gear and the input gear, which shortens the life of the bearing.

Therefore, in a valve opening / closing timing control device that sets the relative rotation phase between the driving side rotating body and the driven side rotating body by the driving force of the electric actuator, it is desired to make the valve compact while improving the durability of the bearing.

The characteristic configuration of the valve opening / closing timing control device according to the present invention includes an input gear that rotates on an eccentric shaft core that is in a parallel posture with the rotating shaft core and has a predetermined eccentric amount with respect to the rotating shaft core. It has a drive-side rotating body that rotates synchronously with the crank shaft of the internal combustion engine around the rotating shaft core, and an output gear that includes an output gear that includes a larger number of teeth than the number of teeth of the input gear. A driven side rotating body that rotates integrally with a cam shaft for opening and closing a valve of an engine, an electric actuator that sets the relative rotation phase of the driving side rotating body and the driven side rotating body, and a tubular shape that is rotated by the electric actuator. An eccentric member, a first bearing that supports the eccentric member, and a second bearing that supports the input gear are provided, and the eccentric shaft core is rotated by rotation of the eccentric member by the driving force of the electric actuator. The relative rotation phase is changed by revolving around the rotation shaft core to change the meshing position between the output gear and the input gear, and the inner diameter of the first bearing is the inner diameter of the second bearing. The point is larger than the value obtained by adding twice the amount of eccentricity.

In this configuration, the eccentric shaft core is revolved around the rotating shaft core by the rotation of the eccentric member by the driving force of the electric actuator, and the input gear provided on the driving side rotating body and the output provided on the driven side rotating body are provided. The relative rotation phase between the driving side rotating body and the driven side rotating body can be changed by changing the meshing position with the gear. As a result, a moment acts on the first bearing that supports the eccentric member and the second bearing that supports the front input gear by receiving a reaction force from the meshing portion, and durability becomes a problem. Therefore, it is desirable that the first bearing and the second bearing are close to each other in the direction of the axis of rotation.

By the way, in the input gear provided on the drive side rotating body, the eccentric shaft core revolves around the rotating shaft core by a predetermined amount of eccentricity, so that the inner peripheral surface of the second bearing is deviated in the radial direction around the rotating shaft core. The amount of movement is twice the amount of core. That is, if the inner diameter of the first bearing is made larger than the value obtained by adding twice the eccentricity to the inner diameter of the second bearing as in this configuration, the inner peripheral surface of the first bearing when the drive-side rotating body rotates. Is always located radially outside the inner peripheral surface of the second bearing. As a result, even when a leaf spring or the like is arranged on the inner peripheral surface of the second bearing, the first bearing does not interfere with the leaf spring. Therefore, the first bearing and the second bearing can be brought close to each other along the rotation axis direction.

Therefore, the shaft length of the valve opening / closing timing control device can be shortened, and the moment applied to these bearings due to the reaction force received from the meshing portion between the output gear and the input gear can be reduced to improve the durability of the bearing. can. As described above, in the valve opening / closing timing control device that sets the relative rotation phase between the driving side rotating body and the driven side rotating body by the driving force of the electric actuator, the bearing can be made compact while improving the durability.

Another characteristic configuration is that the eccentric member has a first portion in which the first bearing is arranged and a second portion in which the second bearing is arranged, and the second bearing has a diameter of the input gear. It is arranged between the inside in the direction and the radial outside of the second portion of the eccentric member, and is arranged between the radial inside of the second bearing and the radial outside of the eccentric member. 2 A urging member for urging the bearing to the side of the input gear is further provided, and the first portion of the eccentric member has a protruding portion protruding radially outward from the radial outer surface of the urging member. Is formed, and the outer peripheral surface of the protruding portion and the inner peripheral surface of the first bearing are fitted to each other.

If an urging member for urging the second bearing to the side of the input gear is provided as in this configuration, backlash at the meshing portion between the output gear and the input gear can be eliminated. Further, as in this configuration, a protrusion is provided on the first portion of the eccentric member so as to project radially outward from the radial outer surface of the urging member, and the outer peripheral surface of the protrusion and the inner circumference of the first bearing are provided. If the surface is fitted, the protrusion can reliably prevent the urging member from sliding with the first bearing.

Another characteristic configuration is that the urging member and the first bearing partially overlap each other in the radial direction.

If the urging member and the first bearing partially overlap in the radial direction as in this configuration, the first bearing and the second bearing are in a state of being closer to each other in the rotation axis direction. Therefore, the shaft length of the valve opening / closing timing control device can be shortened, and the durability of the bearing can be reliably improved.

Another characteristic configuration is that the drive-side rotating body further includes a main body portion to which the rotation of the internal combustion engine is transmitted, and an old dam joint for connecting the input gear to the main body portion, and the first bearing and the second bearing. The bearings are arranged close to the rotating shaft core, and the Oldham joint is arranged along the rotating shaft core on a side farther from the cam shaft than both the first bearing and the second bearing. There is a point.

According to this configuration, the drive-side rotating body further includes a main body portion to which the rotation of the internal combustion engine is transmitted and an old dam joint for connecting the input gear to the main body portion, and the old dam joint is the first bearing in the direction along the rotation axis. It is located farther from the camshaft than both the second bearing and the second bearing. Therefore, the first bearing and the second bearing can be easily brought close to each other in the rotation axis direction without an old dam joint intervening between the first bearing and the second bearing.

Another characteristic configuration is that the eccentric member has protrusions protruding radially outward on the side closer to the cam shaft than both the first bearing and the second bearing in the direction along the axis of rotation. The protrusion is sandwiched between the first bearing and the driven side rotating body in the direction along the rotating shaft core.

The eccentric member receives a reaction force from the meshing portion between the output gear and the input gear, and easily moves in the direction of the axis of rotation. By arranging the protrusion of the eccentric member between the first bearing and the driven side rotating body as in this configuration, the eccentric member is prevented from moving in the direction of the rotation axis, and smooth rotation is achieved. It can be realized. Moreover, since the protrusions of the eccentric member are arranged closer to the camshaft than both the first bearing and the second bearing, the protrusions do not intervene between the first bearing and the second bearing. The first bearing and the second bearing can be easily brought close to each other in the direction of the axis of rotation.

It is sectional drawing of the valve opening / closing timing control device. FIG. 2 is a sectional view taken along line II-II of FIG. FIG. 3 is a sectional view taken along line III-III of FIG. FIG. 6 is a sectional view taken along line IV-IV of FIG. It is an exploded perspective view of the valve opening / closing timing control device.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[Basic configuration]
As shown in FIG. 1, a drive-side rotating body A that rotates synchronously with the crank shaft 1 of the engine E as an internal combustion engine and a rotating shaft core X, and a rotating shaft arranged inside the drive-side rotating body A in the radial direction. Set the relative rotation phase between the driven side rotating body B that rotates integrally with the intake cam shaft 2 (an example of the cam shaft) for opening and closing the valve around the core X, and the driving side rotating body A and the driven side rotating body B. The valve opening / closing timing control device 100 is configured with a phase control motor M (an example of an electric actuator) composed of an electric motor. The valve opening / closing timing control device 100 is arranged between the phase control motor M and the intake camshaft 2 in the direction along the rotation axis X.

The engine E is configured as a 4-cycle type in which a piston 4 is housed in a plurality of cylinders 3 formed in a cylinder block, and the piston 4 is connected to a crankshaft 1 by a connecting rod 5. A timing chain 6 (a timing belt or the like) is wound around the output sprocket 1S of the crankshaft 1 of the engine E and the drive sprocket 11S of the drive side rotating body A. As a result, the rotation of the crankshaft 1 of the engine E is transmitted to the drive-side rotating body A.

As a result, when the engine E is in operation, the entire valve opening / closing timing control device 100 rotates about the rotation axis X. Further, the driving force of the phase control motor M activates the phase adjusting mechanism C, which will be described later, so that the driven side rotating body B can be displaced relative to the driving side rotating body A in the same direction as the rotation direction or in the opposite direction. By this displacement, the relative rotation phase between the driving side rotating body A and the driven side rotating body B is set, and the opening / closing timing (opening / closing timing) of the intake valve 2B is controlled by the cam portion 2A of the intake camshaft 2.

The operation in which the driven side rotating body B is displaced in the same direction as the driving side rotating body A is referred to as an advance angle operation, and the intake compression ratio is increased by this advance angle operation. Further, the operation in which the driven side rotating body B is displaced in the opposite direction to the driving side rotating body A is referred to as a retard angle operation, and the intake compression ratio is reduced by this retard angle operation.

[Valve opening / closing timing control device]
As shown in FIGS. 1 to 4, the drive-side rotating body A includes a cylindrical main body Aa centered on a rotating shaft core X, an oldham joint Cx that rotates synchronously with the main body Aa, and an input gear 30. ing. The main body Aa is configured by fastening the outer case 11 having the drive sprocket 11S formed on the outer periphery thereof and the front plate 12 with a plurality of fastening bolts 13. The outer case 11 is a bottomed tubular type having an opening at the bottom. The Oldham joint Cx and the input gear 30 that form a part of the drive-side rotating body A also function as the phase adjusting mechanism C described later. The input gear 30 is connected to the main body Aa via the Oldham joint Cx.

An intermediate member 20 (an example of a driven side rotating body B) and a phase adjusting mechanism C having a hypocycloid type gear reduction mechanism are housed in the internal space of the outer case 11. Further, the phase adjusting mechanism C includes an old dam joint Cx that reflects the phase change on the driving side rotating body A and the driven side rotating body B, and this old dam joint Cx has an intermediate member 20 and a front plate in the rotation axis X direction. It is arranged between 12 and 12. A lubrication recess 12a, which is a slight gap in the rotation axis X direction, is formed on the surface of the front plate 12 facing the Oldham joint Cx.

The intermediate member 20 constituting the driven side rotating body B has a support wall portion 21 connected to the intake camshaft 2 in a posture orthogonal to the rotating shaft core X, and a cylindrical intake camshaft centered on the rotating shaft core X. A cylindrical wall portion 22 projecting in a direction away from 2 is integrally formed.

The intermediate member 20 is inserted so as to be relatively rotatable in a state where the outer surface of the tubular wall portion 22 is in contact with the inner surface of the outer case 11, and is taken in by a connecting bolt 23 inserted through a through hole in the center of the support wall portion 21. It is fixed to the end of the camshaft 2. In the fixed state in this way, the outer end (the side farther from the intake camshaft 2) of the tubular wall portion 22 in the direction along the rotary shaft core X is inside (the side farther from the intake camshaft 2) in the direction along the rotary shaft core X than the front plate 12. It is configured to be located on the side closer to the intake camshaft 2. An opening 21a for guiding oil is formed inside the eccentric member 26 on a part of the surface of the support wall portion 21 of the intermediate member 20 that comes into contact with the intake camshaft 2.

The phase control motor M is supported by the engine E by a support frame 7 so that its output shaft Ma is arranged on a coaxial core with the rotary shaft core X. A pair of engaging pins 8 having a posture orthogonal to the rotation shaft core X are formed on the output shaft Ma of the phase control motor M.

[Phase adjustment mechanism]
As shown in FIGS. 1 to 5, the phase adjusting mechanism C is composed of a plurality of members so as to change the relative rotation phase between the driving side rotating body A and the driven side rotating body B by the driving force of the phase control motor M. ing. The phase adjusting mechanism C includes an intermediate member 20, an output gear 25 formed on the inner peripheral surface of the tubular wall portion 22 of the intermediate member 20, an eccentric member 26, and a leaf spring 27 (an example of an urging member). A first bearing 28, a second bearing 29, a fixing ring 31, an Oldham joint Cx, and an input gear 30 are provided. The first bearing 28 and the second bearing 29 are ball bearings having inner rings 28a and 29a and outer rings 28b and 29b, respectively.

Of the inner circumference of the tubular wall portion 22 of the intermediate member 20, a support surface 22S centered on the rotary shaft core X is formed inside (a position adjacent to the support wall portion 21) in the direction along the rotary shaft core X. An output gear 25 centered on the rotary shaft core X is integrally formed on the outer side (the side farther from the intake camshaft 2) in the direction along the rotary shaft core X from the support surface 22S.

The eccentric member 26 has a cylindrical shape, and the eccentric member 26 is in the radial direction of the driven side rotating body B (intermediate member 20) on the inner side (the side closer to the intake camshaft 2) in the direction along the rotating shaft core X. The first portion 26A that supports the inside and the second portion 26B that supports the radial inside of the drive-side rotating body A (input gear 30) on the outside (the side farther from the intake camshaft 2) along the rotation shaft core X. And have. The second portion 26B has an eccentricity that is an outer peripheral surface centered on the eccentric shaft core Y that is parallel to the rotation shaft core X and eccentric with respect to the rotation shaft core X with a predetermined eccentricity amount Dy. A support surface 26E is formed (see FIG. 3). A leaf spring 27 is fitted in a recess 26F formed on the outer periphery of the eccentric support surface 26E. Further, the first portion 26A is formed with a protruding portion 26S protruding radially outward from the radial outer surface of the leaf spring 27. A circumferential support surface 26Sa centered on the rotation axis X is formed on the outer peripheral surface of the protrusion 26S (see FIG. 2).

On the inner circumference of the eccentric member 26, a pair of engaging grooves 26T to which each of the pair of engaging pins 8 of the phase control motor M can be engaged are formed in a posture parallel to the rotary shaft core X (FIG. 4). reference). Further, an annular protrusion 26a projecting radially outward is formed at an end portion on the inner side (side of the support wall portion 21) in the direction along the rotation axis core X of the eccentric member 26. The protrusion 26a is sandwiched between the support wall portion 21 of the driven side rotating body B and the first bearing 28 in the direction along the rotating shaft core X, and has a function of preventing the eccentric member 26 from coming off. ..

As shown in FIGS. 1 to 3, the eccentric member 26 has a circumferential support surface 26Sa (outer peripheral surface of the protruding portion 26S) press-fitted into the inner peripheral surface of the inner ring 28a of the first bearing 28 (an example of fitting). The eccentric support surface 26E is in contact with a part of the inner peripheral surface of the inner ring 29a of the second bearing 29 in a fitted state by the urging force of the leaf spring 27. Further, the outer peripheral surface of the outer ring 28b of the first bearing 28 is press-fitted into the support surface 22S of the tubular wall portion 22 of the driven side rotating body B (intermediate member 20), and the outer peripheral surface of the outer ring 29b of the second bearing 29 is an input gear. It is press-fitted into the inner peripheral surface of 30. At this time, the tubular wall portion 22 supports the first bearing 28 in the radial direction, the first bearing 28 supports the eccentric member 26 in the radial direction, and the eccentric member 26 supports the second bearing 29 in the radial direction. However, the second bearing 29 supports the input gear 30 in the radial direction. That is, the first bearing 28 is arranged between the radial inside of the driven side rotating body B (intermediate member 20) and the radial outside of the first portion 26A of the eccentric member 26, and the second bearing 29 is on the drive side. It is arranged between the radial inside of the rotating body A (input gear 30) and the radial outside of the second portion 26B of the eccentric member 26. That is, the first bearing 28 is supported by the driven side rotating body B and supports the eccentric member 26, and the second bearing 29 is supported by the eccentric member 26 and supports the input gear 30. The eccentric member 26 and the inner ring 28a of the first bearing 28 are press-fitted, the driven side rotating body B and the outer ring 28b of the first bearing 28 are press-fitted, and the input gear 30 and the outer ring 29b of the second bearing 29 are press-fitted. Is not particularly limited as long as both members can rotate integrally. Further, the first bearing 28 is not limited to a configuration in which the first bearing 28 is directly supported by the tubular wall portion 22 and directly supports the eccentric member 26. The first bearing 28 may be supported by the tubular wall portion 22 via another member arranged between the tubular wall portion 22 and the first bearing 28, or the first bearing 28 and the eccentric member 26 The first bearing 28 may support the eccentric member 26 via another member arranged between the bearings. The same applies to the second bearing 29. That is, the second bearing 29 is not limited to the configuration in which it is directly supported by the eccentric member 26 and directly supports the input gear 30. The second bearing 29 may be supported by the eccentric member 26 via another member arranged between the eccentric member 26 and the second bearing 29, or between the second bearing 29 and the input gear 30. The second bearing 29 may support the input gear 30 via another arranged member.

In the present embodiment, the inner diameter D1 of the first bearing 28, which is the diameter of the inner peripheral surface of the inner ring 28a of the first bearing 28, is the inner diameter of the second bearing 29, which is the diameter of the inner peripheral surface of the inner ring 29a of the second bearing 29. It is configured to be larger than the value obtained by adding twice the eccentricity amount Dy to D2. Further, the leaf spring 27 and the first bearing 28 partially overlap each other in the radial direction. Therefore, the first bearing 28 and the second bearing 29 are in a state of being close to each other in the rotation axis X direction.

In this phase adjusting mechanism C, the number of teeth of the external tooth portion 30A of the input gear 30 is set to be one tooth less than the number of teeth of the internal tooth portion 25A of the output gear 25. Then, a part of the outer tooth portion 30A of the input gear 30 meshes with a part of the inner tooth portion 25A of the output gear 25.

The leaf spring 27 is composed of a pair of bending members obtained by bending a spring plate material into a U shape, and a part of the outer tooth portion 30A of the input gear 30 is bitten into a part of the inner tooth portion 25A of the output gear 25. An urging force is applied to the input gear 30 so as to match. By the urging force of the leaf spring 27, backlash in the meshing portion between the input gear 30 and the output gear 25 can be eliminated. The pair of bending members of the leaf spring 27 are installed at predetermined positions by the guide convex portion 26F formed in the concave portion 26F of the eccentric support surface 26E (see FIG. 4). In the present embodiment, the length of the leaf spring 27 in the rotation shaft core X direction is larger than the length of the second bearing 29 in the rotation shaft core X direction, and the center of the leaf spring 27 along the rotation shaft core X direction. The positional relationship between the leaf spring 27 and the second bearing 29 is defined so as to coincide with the center of the second bearing 29 along the rotation axis X direction (see FIG. 1). As a result, the urging force of the leaf spring 27 can be evenly applied to the second bearing 29, so that backlash at the meshing portion between the input gear 30 and the output gear 25 can be reliably eliminated.

The fixing ring 31 is a C-shaped annular member, and is an annular member formed in the circumferential direction on the outer side (the side farther from the intake camshaft 2) in the rotation axis X direction than the eccentric support surface 26E of the eccentric member 26. By fixing the fixing ring 31 to the groove 26Ea in the fitted state, the second bearing 29 is prevented from coming off (see FIG. 5).

As shown in FIGS. 1, 4, and 5, the orthogonal joint Cx has a central annular portion 41 and a pair of annular portions 41 protruding outward in the radial direction along a first direction (left-right direction in FIG. 4). An external engaging arm 42 and an internal engaging arm 43 projecting radially outward along a second direction (vertical direction in FIG. 4) orthogonal to the first direction from the annular portion 41 are integrally formed. It is composed of joint members. Each of the pair of internal engaging arms 43 is formed with an engaging recess 43a connected to the opening of the annular portion 41.

Of the outer case 11, a pair of guide groove portions 11a extending in the radial direction about the rotation axis X from the internal space to the external space of the outer case 11 are through grooves at the opening edge portion where the front plate 12 abuts. It is formed in a shape. The groove width of the guide groove portion 11a is set to be slightly wider than the width of the external engaging arm 42, and a pair of discharge flow paths 11b for discharging the lubricating oil are formed in each guide groove portion 11a. The discharge flow path 11b may be formed on the front plate 12.

The input gear 30 is an annular member having a plurality of external tooth portions 30A in the circumferential direction, and is eccentric with a posture parallel to the rotation shaft core X and a predetermined eccentricity amount Dy with respect to the rotation shaft core X. Rotates around the eccentric shaft core Y. A pair of engaging protrusions 30T are integrally formed on the end surface of the input gear 30 facing the front plate 12. The engagement width of the engagement protrusion 30T is set to be slightly narrower than the engagement width of the engagement recess 43a of the internal engagement arm 43.

From such a configuration, the pair of external engaging arms 42 of the Oldham joint Cx are engaged with the pair of guide groove portions 11a of the outer case 11, and the engaging recesses 43a of the pair of internal engaging arms 43 of the Oldam joint Cx are engaged. By engaging the pair of engaging protrusions 30T of the input gear 30, the oldham joint Cx can be made to function.

At this time, the oldham joint Cx can be displaced in the first direction (left-right direction in FIG. 4) in which the external engaging arm 42 projects with respect to the outer case 11, and the internal engaging arm 43 engages with the oldam joint Cx. The input gear 30 can be freely displaced in the second direction (vertical direction in FIG. 4) along the forming direction of the joint recess 43a.

As shown in FIG. 1, the lubricating oil supplied from the oil pump P is inside the eccentric member 26 from the lubricating oil passage 15 of the intake camshaft 2 via the opening 21a of the support wall portion 21 of the intermediate member 20. It is supplied to the space. The lubricating oil supplied in this way is supplied to the first bearing 28 from the gap between the protrusion 26a of the eccentric member 26 and the support wall portion 21 of the driven side rotating body B by centrifugal force, and the first bearing 28 operates smoothly. Let me. At the same time, the lubricating oil in the internal space of the eccentric member 26 is supplied to the Oldham joint Cx by centrifugal force and also to the second bearing 29, and is supplied to the internal tooth portion 25A of the output gear 25 and the external teeth of the input gear 30. It is supplied to and from the portion 30A. Then, the lubricating oil supplied to the Oldham joint Cx is discharged to the outside through the gap between the external engaging arm 42 of the Oldam joint Cx and the guide groove portion 11a of the outer case 11.

In particular, since the discharge flow path 11b is formed in the guide groove portion 11a, when the engine E in a stopped state in a cold environment is started, the internal lubricating oil is swiftly passed through the discharge flow path 11b by centrifugal force. Is discharged to. Therefore, the highly viscous lubricating oil is discharged in a short time, the influence of the viscosity of the lubricating oil is eliminated, and the phase adjusting mechanism C can be operated quickly.

In the valve open / close timing control device 100 in the assembled state, as shown in FIG. 1, the support wall portion 21 of the intermediate member 20 is connected to the end of the intake camshaft 2 by the connecting bolt 23, and the intake camshaft 2 and the intermediate member are connected to each other. 20 and 20 rotate integrally. The eccentric member 26 is rotatably supported by the first bearing 28 with respect to the intermediate member 20 about the rotary shaft core X. As shown in FIGS. 1 and 2, the input gear 30 is supported by the second bearing 29 with respect to the eccentric support surface 26E of the eccentric member 26, and the external teeth of the input gear 30 are supported by the urging force of the leaf spring 27. A part of the portion 30A meshes with a part of the internal tooth portion 25A of the output gear 25.

Further, as shown in FIG. 4, the external engaging arm 42 of the Oldham joint Cx engages with the pair of guide groove portions 11a of the outer case 11, and the input gear 30 fits into the engaging recess 43a of the internal engaging arm 43 of the Oldam joint Cx. The engaging protrusion 30T of the above engages. Since the front plate 12 is arranged on the outer side of the Oldham joint Cx as shown in FIG. 1, the Oldam joint Cx can move in the direction orthogonal to the rotation axis X while in contact with the inner surface of the front plate 12. Will be. Due to this arrangement, the Oldham joint Cx is outside the rotation shaft core X direction (farther side from the intake camshaft 2) from both the first bearing 28 and the second bearing 29, and is in the rotation shaft core X direction from the front plate 12. It is arranged inside (the side closer to the intake camshaft 2).

Then, as shown in FIGS. 1 to 3, a pair of engaging pins 8 formed on the output shaft Ma of the phase control motor M are engaged with the engaging groove 26T of the eccentric member 26.

[Operating mode of phase adjustment mechanism]
The phase control motor M is controlled by a control device (not shown) configured as an ECU. The engine E is equipped with a sensor (not shown) capable of detecting the rotation speed (rotational speed per unit time) of the crankshaft 1 and the intake camshaft 2 and the respective rotation phases, and detection of these sensors. The signal is configured to be input to the controller.

The control device maintains the relative rotational phase by driving the phase control motor M at a speed equal to the rotational speed of the intake camshaft 2 when the engine E is operating. On the other hand, the advance angle operation is performed by reducing the rotation speed of the phase control motor M from the rotation speed of the intake camshaft 2, and conversely, the retard angle operation is performed by increasing the rotation speed. As described above, the intake compression ratio is increased by the advance angle operation, and the intake compression ratio is decreased by the retard angle operation.

When the phase control motor M rotates at a constant speed (constant speed with the intake camshaft 2) with the outer case 11, the meshing position of the outer tooth portion 30A of the input gear 30 with respect to the inner tooth portion 25A of the output gear 25 does not change. Therefore, the relative rotation phase of the driven side rotating body B with respect to the driving side rotating body A is maintained.

On the other hand, by driving and rotating the output shaft Ma of the phase control motor M at a speed higher or lower than the rotation speed of the outer case 11, the eccentric shaft core Y in the phase adjusting mechanism C revolves around the rotation shaft core X. Due to this revolution, the meshing position of the input gear 30 with respect to the inner tooth portion 25A of the output gear 25 with respect to the outer tooth portion 30A is displaced along the inner circumference of the output gear 25, and a rotational force is generated between the input gear 30 and the output gear 25. Works. That is, a rotational force centered on the rotary shaft core X acts on the output gear 25, and a rotational force that tries to rotate around the eccentric shaft core Y acts on the input gear 30.

As described above, the input gear 30 does not rotate with respect to the outer case 11 because its engaging protrusion 30T engages with the engaging recess 43a of the internal engaging arm 43 of the Oldham joint Cx, and is a drive-side rotating body. The rotational force of the main body Aa of A acts on the output gear 25. Due to the action of this rotational force, the intermediate member 20 together with the output gear 25 rotates about the rotation shaft core X with respect to the outer case 11. As a result, the relative rotation phase between the driving side rotating body A and the driven side rotating body B is set, and the opening / closing timing is set by the intake camshaft 2.

Further, when the eccentric shaft core Y of the input gear 30 revolves around the rotating shaft core X, the external engaging arm 42 of the Oldham joint Cx protrudes from the outer case 11 due to the displacement of the input gear 30. The input gear 30 is displaced in the direction in which the internal engaging arm 43 protrudes (second direction).

As described above, since the number of teeth of the external tooth portion 30A of the input gear 30 is set to be one tooth less than the number of teeth of the internal tooth portion 25A of the output gear 25, the eccentric shaft core Y of the input gear 30 rotates. When it revolves about one rotation around the shaft core X, the output gear 25 rotates by one tooth, and a large deceleration is realized.

[Action / effect of the embodiment]
As described above, in the present embodiment, the eccentric shaft core Y is revolved by the rotation of the eccentric member 26 by the driving force of the phase control motor M, and the input gear 30 and the driven side rotation provided on the driving side rotating body A are rotated. The relative rotation phase can be changed by changing the meshing position with the output gear 25 provided on the body B. As a result, the first bearing 28 arranged between the radial inner side of the driven side rotating body B (intermediate member 20) and the radial outer side of the first portion 26A of the eccentric member 26, and the driving side rotating body A (input). A moment acts on the second bearing 29 arranged between the radial inner side of the gear 30) and the radial outer side of the second portion 26B of the eccentric member 26 by receiving a reaction force from the meshing portion. Durability becomes an issue. Therefore, it is desirable that the first bearing 28 and the second bearing 29 are close to each other in the rotation axis X direction.

Therefore, as shown in FIG. 1, in the present embodiment, the inner diameter D1 of the first bearing 28 is configured to be larger than the value obtained by adding twice the eccentricity Dy to the inner diameter D2 of the second bearing 29. This is arranged between the radial inside of the drive-side rotating body A and the radial outside of the eccentric member 26 because the eccentric shaft core Y of the input gear 30 provided on the driving-side rotating body A revolves. This is because the amount of movement of the inner peripheral surface of the second bearing 29 is twice the amount of eccentricity Dy in the radial direction about the rotating shaft core X. That is, if the inner diameter D1 of the first bearing 28 is made larger than the value obtained by adding twice the eccentricity amount Dy to the inner diameter D2 of the second bearing 29 as in the present embodiment, the driving side rotating body A becomes the first in rotation. The inner peripheral surface of the 1 bearing 28 is always located radially outside the inner peripheral surface of the second bearing 29. As a result, the first bearing 28 does not interfere with the leaf spring 27 arranged on the inner peripheral surface of the second bearing 29. Therefore, the first bearing 28 and the second bearing 29 can be brought close to each other along the rotation axis X direction. In particular, in the present embodiment, the leaf spring 27 and the first bearing 28 partially overlap each other in the radial direction. As a result, the first bearing 28 and the second bearing 29 are in a state closer to each other in the rotation axis X direction.

Therefore, the shaft length of the valve opening / closing timing control device 100 can be shortened, and the moment applied to the bearings 28 and 29 due to the reaction force received from the meshing portion between the output gear 25 and the input gear 30 can be reduced to reduce the moment applied to the bearings 28 and 29. , 29 can be improved in durability.

Further, since the outer peripheral surface (circumferential support surface 26Sa) of the protruding portion 26S protrudes from the radial outer surface of the leaf spring 27, the protruding portion 26S ensures sliding contact between the leaf spring 27 and the first bearing 28. Can be prevented.

Further, since the oldham joint Cx is made of a plate material, the valve opening / closing timing control device 100 can be miniaturized in the direction along the rotation axis X. The Oldham joint Cx is arranged on the side of the intake camshaft 2 farther from both the first bearing 28 and the second bearing 29 in the direction along the rotation shaft core X. Therefore, the first bearing 28 and the second bearing 29 can be easily brought close to each other in the rotation axis X direction without the old dam joint Cx intervening between the first bearing 28 and the second bearing 29.

Further, the eccentric member 26 has a protrusion 26a protruding outward in the radial direction on the side closer to the intake cam shaft 2 than both the first bearing 28 and the second bearing 29 in the direction along the rotation shaft core X. The protrusion 26a is sandwiched between the first bearing 28 and the driven side rotating body B in the direction along the rotating shaft core X. Therefore, the stress that receives the reaction force from the meshing portion between the output gear 25 and the input gear 30 and moves the eccentric member 26 to the side far from the intake cam shaft 2 along the rotation axis X direction is the eccentric member. Even when acting on 26, the protrusion 26a abuts on the first bearing 28, and the stress is received by the press-fitting surface of the first bearing 28 and the support surface 22S of the cylindrical wall portion 22 of the driven side rotating body B, resulting in bias. The movement of the core member 26 can be prevented. Moreover, since the protrusion 26a of the eccentric member 26 is arranged closer to the intake camshaft 2 than both the first bearing 28 and the second bearing 29, it is located between the first bearing 28 and the second bearing 29. The first bearing 28 and the second bearing 29 can be easily brought close to each other in the rotation axis X direction without the intervention of the protrusion 26a.

Further, the circumferential support surface 26Sa of the eccentric member 26 supports the support surface 22S which is the inner peripheral surface of the intermediate member 20 via the first bearing 28, and the eccentric support surface 26E of the eccentric member 26 is the second bearing. The inner peripheral surface of the input gear 30 is supported via 29. Therefore, even if the urging force of the leaf spring 27 acts in the direction of changing the posture of the eccentric member 26, the entire circumference of the circumferential support surface 26Sa of the eccentric member 26 is the inner circumference of the intermediate member 20 due to the first bearing 28. It is held so as to be embraced by the eccentric member 26, and the positional relationship between the eccentric member 26 and the intermediate member 20 can be maintained.

In particular, in this configuration, the urging force of the leaf spring 27 acts only between the eccentric member 26 and the intermediate member 20 and does not act on the external member. Therefore, for example, the urging force of the leaf spring 27 acts on the external member. It is not necessary to consider deformation and displacement, and the posture of the eccentric member 26 can be maintained with higher accuracy.

[Another Embodiment]
(1) In the above-described embodiment, the urging force of the leaf spring 27 is applied to the input gear 30 to eliminate backlash at the meshing portion between the input gear 30 and the output gear 25, but the leaf spring 27 is omitted. Is also good. Even in this case, the input gear 30 and the output gear 25 mesh with each other, so that the drive-side rotating body A and the driving-side rotating body A can be integrally rotated.
(2) In the above-described embodiment, the oldham joint Cx is composed of a plate-shaped joint member, but for example, as described in the above-mentioned Patent Document 1 (Japanese Patent Laid-Open No. 2008-38886), the drive-side rotating body A The old dam joint Cx may be omitted by forming an internal gear portion on the inner peripheral surface and engaging the internal gear portion with the input gear 30. In this case, the first bearing 28 may be arranged between the radial inside of the front plate 12 of the drive-side rotating body A and the radial outside of the eccentric member 26.
(3) In the above-described embodiment, the first bearing 28 that supports the eccentric member 26 is directly supported by the tubular wall portion 22 of the intermediate member 20 (driven rotating body), but the present invention is not limited to this. do not have. As in Patent Document 1, the planetary bearing (corresponding to the first bearing 28 of the present embodiment) is a separate member arranged between the planetary bearing and the driven side rotating body (corresponding to the intermediate member 20 of the present embodiment). It may be supported by the driven side rotating body via the vehicle.
(4) In the above-described embodiment, the valve opening / closing timing control device 100 is provided on the intake side of the engine E, but the valve opening / closing timing control device 100 may be provided on the exhaust side of the engine E.

The present invention can be used in a valve opening / closing timing control device that sets the relative rotation phase between the driving side rotating body and the driven side rotating body by the driving force of the electric actuator.

1 Crankshaft 2 Intake camshaft (camshaft)
25 Output gear 26 Eccentric member 26A First part 26B Second part 26S Protruding part 26Sa Circumferential support surface (outer peripheral surface)
26a Protrusion 27 Spring body (urgency member)
28 1st bearing 29 2nd bearing 30 Input gear 100 Valve opening / closing timing control device A Drive side rotating body B Driven side rotating body Cx Oldham joint D1 Inner diameter of 1st bearing D2 Inner diameter of 2nd bearing D E. institution)
M phase control motor (electric actuator)
X Rotating shaft core Y Eccentric shaft core

Claims (5)

It has an input gear that rotates in an eccentric shaft core that is parallel to the rotating shaft core and has a predetermined amount of eccentricity with respect to the rotating shaft core, and rotates synchronously with the crank shaft of the internal combustion engine around the rotating shaft core. Drive side rotating body and
A driven side rotating body having an output gear having a number of teeth larger than the number of teeth of the input gear and rotating integrally with the camshaft for opening and closing the valve of the internal combustion engine on a coaxial core with the rotating shaft core.
An electric actuator that sets the relative rotation phase of the driving side rotating body and the driven side rotating body, and
A cylindrical eccentric member rotated by the electric actuator and
The first bearing that supports the eccentric member and
A second bearing that supports the input gear is provided.
The relative rotation phase is changed by revolving the eccentric shaft core around the rotation shaft core by the rotation of the eccentric member by the driving force of the electric actuator and changing the meshing position between the output gear and the input gear. Changed,
A valve opening / closing timing control device in which the inner diameter of the first bearing is larger than the value obtained by adding twice the eccentricity to the inner diameter of the second bearing. The eccentric member has a first portion in which the first bearing is arranged and a second portion in which the second bearing is arranged.
The second bearing is arranged between the radial inside of the input gear and the radial outside of the second portion of the eccentric member.
Further provided with an urging member arranged between the radial inner side of the second bearing and the radial outer side of the eccentric member to urge the second bearing toward the input gear.
A protrusion is formed in the first portion of the eccentric member so as to project radially outward from the radial outer surface of the urging member, and the outer peripheral surface of the protrusion and the inside of the first bearing. The valve opening / closing timing control device according to claim 1, wherein the peripheral surface is fitted to the peripheral surface. The valve opening / closing timing control device according to claim 2, wherein the urging member and the first bearing partially overlap each other in a radial direction. The drive-side rotating body further includes a main body portion to which the rotation of the internal combustion engine is transmitted, and an oldham joint for connecting the input gear to the main body portion.
The first bearing and the second bearing are arranged close to each other in the direction of the axis of rotation.
13. Valve opening / closing timing control device. The eccentric member has a protrusion that protrudes radially outward on the side closer to the camshaft than both the first bearing and the second bearing in the direction along the rotary shaft core.
The valve opening / closing timing control device according to any one of claims 1 to 4, wherein the protrusion is sandwiched between the first bearing and the driven side rotating body in a direction along the rotating shaft core.

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