This application is based on Japanese Patent Application No. 2014-209565 filed on Oct. 13, 2014, the disclosure of which is incorporated herein by reference in its entirety.
The present disclosure relates to a valve timing controller.
A valve timing controller is attached to an internal combustion engine to control a valve timing of valve opened and closed by a camshaft. JP 5240309 B2 (US 2010/0180845 A1) describes a valve timing controller equipped with a driving rotor supported by a journal portion from a radially inner side to rotate with a crankshaft, a driven rotor rotating with a camshaft inside of the driving rotor, and a planet gear engaged with the driving rotor and the driven rotor to control a rotation phase of the driven rotor relative to the driving rotor by carrying out planet movement. The driven rotor has a contact surface in contact with a tip end of a chamfering portion, and a feed port passing through the driven rotor in an axial direction to introduce lubricant supplied from the camshaft into the driving rotor.
In the contact surface of the driven rotor in contact with the camshaft, the outer edge part of the feed port is located at the radially same position as the outer circumference part of the journal portion, or is positioned on the radially outer side of the outer circumference part. In these cases, the lubricant lubricating the interface of the journal portion may decrease.
The camshaft may have a chamfering portion at which the diameter is decreased as extending from the journal portion toward the tip end, in consideration of the workability and safety for a worker at the assembling time. However, at the feed port, if the outer edge part of the chamfering portion is located on the radially inner side of the tip end of the camshaft, introduction of the lubricant may be affected.
It is an object of the present disclosure to provide a valve timing controller in which lubricant easily lubricates various parts.
According to an aspect of the present disclosure, for an internal combustion engine having a camshaft with a journal portion and a chamfering portion, a valve timing controller includes a driving rotor, a driven rotor and a planet gear, and controls valve timing of a valve opened and closed by the camshaft using a torque transferred from a crankshaft. A diameter of the chamfering portion decreases as extending from the journal portion toward a tip end of the camshaft. The driving rotor is supported by the journal portion from a radially inner side to rotate with the crankshaft. The driven rotor rotates with the camshaft inside of the driving rotor. The planet gear is engaged with the driving rotor and the driven rotor to control a rotation phase of the driven rotor relative to the driving rotor by carrying out planet movement. The driven rotor has a contact surface in contact with a tip end of the chamfering portion, and a feed port passing through the driven rotor in an axial direction to introduce lubricant supplied from the camshaft into the driving rotor. The feed port has an outer edge part located on a radially outer side. The outer edge part, on a side adjacent to the contact surface, is located on a radially outer side of the tip end of the chamfering portion and is located on a radially inner side of an outer circumference part of the journal portion.
Accordingly, the lubricant supplied from the camshaft is introduced into the driving rotor from the feed port. The outer edge part of the feed port is at least located on the outer side of the tip end of the chamfering portion in the radial direction, so lubricant easily and smoothly infiltrates into the interface of the contact surface and the journal portion. Moreover, the outer edge part of the feed port is located on the inner side of the outer circumference part of the journal portion in the radial direction, so lubricant further easily infiltrates into the interface of the journal portion by centrifugal force. Thus, lubricant easily lubricates various parts in the valve timing controller.
According to an aspect of the present disclosure, for an internal combustion engine having a camshaft with a journal portion and a chamfering portion, a valve timing controller includes a driving rotor, a driven rotor and a planet gear, and controls valve timing of a valve opened and closed by the camshaft using a torque transferred from a crankshaft. A diameter of the chamfering portion decreases as extending from the journal portion toward a tip end of the camshaft. The driving rotor is supported by the journal portion from a radially inner side to rotate with the crankshaft. The driven rotor rotates with the camshaft inside of the driving rotor. The planet gear is engaged with the driving rotor and the driven rotor to control a rotation phase of the driven rotor relative to the driving rotor by carrying out planet movement. The driven rotor has a contact surface in contact with a tip end of the chamfering portion, and a feed port passing through the driven rotor in an axial direction to introduce lubricant supplied from the camshaft into the driving rotor. The feed port has an outer edge part located on a radially outer side. A diameter of the outer edge part is smaller on an opposite side opposite from the contact surface in contact with the camshaft than that on the contact surface. The outer edge part, on the opposite side, is located on a radially inner side of an outer circumference part of the journal portion. The outer edge part, on the contact surface, is located on a radially outer side of a tip end of the chamfering portion.
Accordingly, the lubricant supplied from the camshaft is introduced into the driving rotor from the feed port. The outer edge part of the feed port on the opposite side of the camshaft opposite from the contact surface is at least located on the radially inner side of the outer circumference part of the journal portion, so lubricant easily infiltrates into the interface of the journal portion by centrifugal force. The outer edge part on the contact surface is located on the radially outer side of the tip end of the camshaft, so lubricant easily and smoothly infiltrates into the interface of the contact surface and the journal portion. Thus, lubricant easily lubricates various parts in the valve timing controller.
The above and other objects, features and advantages of the present disclosure will become more apparent from the following detailed description made with reference to the accompanying drawings. In the drawings:
Embodiments of the present disclosure will be described hereafter referring to drawings. In the embodiments, a part that corresponds to a matter described in a preceding embodiment may be assigned with the same reference numeral, and redundant explanation for the part may be omitted. When only a part of a configuration is described in an embodiment, another preceding embodiment may be applied to the other parts of the configuration. The parts may be combined even if it is not explicitly described that the parts can be combined. The embodiments may be partially combined even if it is not explicitly described that the embodiments can be combined, provided there is no harm in the combination.
A valve timing controller 100 according to a first embodiment is shown in
The camshaft 1 opens and closes an intake valve of the internal combustion engine by torque transfer, and controls the intake valve to have a suitable valve timing. The camshaft 1 has a journal portion 1a and a chamfering portion 1c. A diameter of the chamfering portion 1c decreases from the journal portion 1a to a tip end 1d of the camshaft 1. An outer circumference part 1b of the camshaft 1 has a cylindrical shape at the journal portion 1a, and has a cone shape at the chamfering portion 1c.
The valve timing controller 100 includes an actuator 10, a power control circuit 20, and a phase controlling mechanism 30.
The actuator 10 is an electric motor such as brushless motor, and has a case 11 and a control shaft 12. The case 11 is fixed to a fix portion of the internal combustion engine, and the control shaft 12 is supported by the case 11 to be able to rotate in both a right direction and a reverse direction.
The power control circuit 20 has a driver, and a microcomputer for controlling the driver, and is arranged outside and/or inside the case 11 and electrically connected with the actuator 10. The power control circuit 20 supplies electricity to the actuator 10 so as to adjust the valve timing according to the operational status of the internal combustion engine, such that the rotation state of the control shaft 12 is controlled.
The phase controlling mechanism 30 has a driving rotor 40, a driven rotor 50, a planet carrier 60, and a planet gear 70.
As shown in
As shown in
As shown in
The peripheral wall part of the driven rotor 50 has a driven side annular-gear part 52 with a tip circle smaller than a root circle. The inside diameter of the driven side annular-gear part 52 is set smaller than the inside diameter of the drive side annular-gear part 46a, and the number of teeth of the driven side annular-gear part 52 is set fewer than the number of teeth of the drive side annular-gear part 46a. The driven side annular-gear part 52 is located between the drive side annular-gear part 46a and the camshaft 1 in the axial direction.
As shown in
As shown in
The planet gear 70 has a stepped cylindrical shape as a whole, and the peripheral wall part has a drive side external-gear part 72 and a driven side external-gear part 74, with a tip circle larger than a root circle. The drive side external-gear part 72 is arranged in the drive side annular-gear part 46a, and geared with the drive side annular-gear part 46a.
In contrast, the driven side external-gear part 74 located between the drive side external-gear part 72 and the fastening part 54 is arranged in the driven side annular-gear part 52, and geared with the driven side annular-gear part 52. The outer diameter of the driven side external-gear part 74 is set smaller than the outer diameter of the drive side external-gear part 72. The number of teeth of the driven side external-gear part 74 and the drive side external-gear part 72 is set smaller respectively than the number of teeth of the driven side annular-gear part 52 and the drive side annular-gear part 46a by the same number.
Thus, the phase controlling mechanism 30 has the planet gear 70 engaged between the driving rotor 40 and the driven rotor 50, and converts the rotational movement of the planet carrier 60 according to the rotation state of the control shaft 12 into the planet movement of the planet gear 70. Therefore, the rotation phase of the driven rotor 50 relative to the driving rotor 40 is controlled to set the valve timing.
Specifically, when the control shaft 12 rotates at the same speed with the driving rotor 40, the planet carrier 60 does not have relative rotation relative to the drive side annular-gear part 46a. Therefore, the external-gear part 72, 74 of the planet gear 70 engaged with the annular-gear parts 46a, 52 has no planet movement, and rotates with the rotors 40 and 50. As a result, since the rotation phase does not change, the valve timing is held at this time.
When the control shaft 12 rotates at a speed higher than the driving rotor 40, the planet carrier 60 has relative rotation on the advance side relative to the drive side annular-gear part 46a. The external-gear part 72, 74 of the planet gear 70 integrally has planet movement while meshing with the annular-gear part 46a, 52. As a result, since the driven rotor 50 carries out relative rotation on the advance side relative to the driving rotor 40, and the rotation phase changes on the advance side, such that the valve timing is advanced at this time.
When the control shaft 12 rotates at a speed lower than the driving rotor 40 or rotates in the reverse direction relative to the driving rotor 40, the planet carrier 60 has relative rotation relative to the drive side annular-gear part 46a. The external-gear part 72, 74 of the planet gear 70 integrally has planet movement while meshing with the annular-gear part 46a, 52. As a result, since the driven rotor 50 carries out relative rotation on the retard side relative to the driving rotor 40, and the rotation phase changes on the retard side, such that the valve timing is retarded at this time.
As shown in
As shown in
The fastening part 54 has a through hole 58 passing through the driven rotor 50 in the axial direction, and the fastening component 55 passes through the through hole 58 having a cylindrical shape. The fastening component 55 is a screw component having an axial part 55a and a head 55b. The axial part 55a passes through the through hole 58 through the projection end 1e of the camshaft 1, and is engaged with the camshaft 1. The fastening part 54 is supported between the head 55b and the camshaft 1, and is fastened to the camshaft 1.
The annular port 56 is continuously extended in the rotational direction of the driven rotor 50, and has a circular based groove shape. The annular port 56 is opened in the contact surface 54a of the fastening part 54. In this embodiment, the outer circumference part of the annular port 56 is located on the radially inner side of the tip end 1d of the chamfering portion 1c and the outer circumference part 1b of the journal portion 1a in the camshaft 1 having the same axis as the annular port 56. The inner periphery part of the annular port 56 is located on the radially inner side of the inner periphery part of the through hole 58 to which the projection end 1e of the camshaft 1 is fitted in the fastening part 54 having the same axis as the annular port 56.
The annular port 56 communicates with a through hole 1f of the camshaft 1 at one place in the extending direction. The through hole 1f sends lubricating oil as a lubricant, and is connected to the pump 2 discharging lubricating oil in response to operation of the internal combustion engine. The lubricating oil breathed out from the pump 2 is supplied to the annular port 56 through the through hole 1f, as shown in
The fastening part 54 has the feed port 57 opened in the inner circumference surface of the through hole 58, and a bottom is defined on the radially outer side of the opening in the shape of a based groove. The feed port 57 passes through the driven rotor 50 in the axial direction, between the contact surface 54a and the opposing surface 54b, and is opened in both of the contact surface 54a and the opposing surface 54b. A positioning component 59 with a pin shape is inserted into the feed port 57 to fit and fix to the camshaft 1, on the radially outer side of the through hole 58 in which the fastening component 55 passes in the fastening part 54, such that the driven rotor 50 is positioned relative to the camshaft 1 in the circumferential direction. That is, the feed port 57 works as an insertion hole of the positioning component 59 when the positioning component 59 is inserted.
As shown in
In the fastening part 54, the feed port 57 communicates to one place of the annular port 56 extended in the rotational direction of the driven rotor 50. The communication part of the feed port 57 communicating with the annular port 56 is set to be deviated (shifted) in the rotational direction of the driven rotor 50 relative to the communication part of the through hole 1f, that is, relative to the supply part of lubricating oil from the through hole 1f. In this embodiment, the communication part is set at a position shifted around the rotation central line RCL by 180 degrees.
Accordingly, as shown in
At this time, as shown in
The driving rotor 40 has the thrust receptacle part 44c projected toward the contact surface 54a from the plane-shaped inner wall surface 44b of the sprocket component 44 to receive the driven rotor 50 in the axial direction. The thrust receptacle part 44c is arranged on the radially outer side of the outer edge part 57a. That is, the feed port 57 and the thrust receptacle part 44c are arranged not to be in contact with each other. The thrust receptacle part 44c is coaxially in contact with the contact surface 54a, thereby the contact surface 54a is supported by the thrust receptacle part 44c.
Furthermore, in this embodiment, the sprocket component 44 of the driving rotor 40 has a pressure regulation hole 44d which releases the pressure of the lubricant between the contact surface 54a of the driven rotor 50 and the inner wall surface 44b of the driving rotor 40, on the radially outer side of the feed port 57. In this embodiment, the pressure regulation hole 44d is located on the radially outer side of the thrust receptacle part 44c.
Advantages of the first embodiment are explained below.
According to the first embodiment, lubricating oil as a lubricant supplied from the camshaft 1 is introduced into the driving rotor 40 from the feed port 57. Since the outer edge part 57a of the feed port 57 in the radial direction is located on the radially outer side of the tip end 1d of the chamfering portion 1c at least, lubricating oil easily and smoothly lubricates the contact surface 54a and the interface of the journal portion 1a. Moreover, since the outer edge part 57a of the feed port 57 in the radial direction is located on the radially inner side of the outer circumference part 1b of the journal portion 1a, lubricating oil further easily infiltrates to the interface of the journal portion 1a by centrifugal force. Thus, lubricating oil can easily lubricate various parts in the valve timing controller 100.
According to the first embodiment, the driving rotor 40 has the thrust receptacle part 44c projected toward the contact surface 54a to receive the driven rotor 50 in the axial direction, and the outer edge part 57a on the contact surface 54a is located on the radially inner side of the thrust receptacle part 44c. Accordingly, an oil film is stably formed between the driven rotor 50 and the driving rotor 40, because the oil film as a liquid film formed from the feed port 57 between the driven rotor 50 and the driving rotor 40 is restricted from being cut by the edge. Thus, the damaging can be controlled.
According to the first embodiment, the driving rotor 40 has the pressure regulation hole 44d to release the pressure of lubricating oil between the driven rotor 50 and the driving rotor 40 on the radially outer side of the feed port 57. Therefore, the driving rotor 40 is restricted from displacing relative to the driven rotor 50 with the pressure of lubricating oil between the driven rotor 50 and the driving rotor 40. As a result, the planet gear 70 can smoothly move.
According to the first embodiment, the valve timing controller further includes a positioning component 59 which positions the driven rotor 50 relative to the camshaft 1, and the positioning component 59 is to be inserted to the feed port 57 as an insertion slot. Therefore, the feed port 57 can be easily formed by using the insertion slot required for positioning as the feed port 57.
As shown in
In the second embodiment, the outer edge part 257a of the feed port 257 in the radial direction is formed so that the diameter decreases as extending away from the contact surface 54a in contact with the camshaft 1. In detail, the outer edge part 257a has one-step level difference as extending away from the contact surface 54a in contact with the camshaft 1.
The deepest point 257b of the outer edge part 257a of the feed port 257, that is opposite from the contact surface 54a (namely, adjacent to the opposing surface 54b) is arranged on the radially inner side of the outer circumference part 1b of the journal portion 1a. Moreover, in this embodiment, the deepest point 257b of the outer edge part 257a opposite from the contact surface 54a is located on the radially inner side of the outer circumference part 1b of the journal portion 1a, and is arranged on the radially inner side of the tip end 1d of the chamfering portion 1c.
On the other hand, the deepest point 257b of the outer edge part 257a adjacent to the contact surface 54a is arranged on the radially outer side of the tip end 1d of the chamfering portion 1c. Moreover, in this embodiment, the deepest point 257b of the outer edge part 257a adjacent to the contact surface 54a is arranged on the radially outer side of the tip end 1d of the chamfering portion 1c, and is arranged on the radially inner side of the outer circumference part 1b of the journal portion 1a. Furthermore, in this embodiment, the outer edge part 257a adjacent to the contact surface 54a is arranged on the radially inner side of the thrust receptacle part 44c. That is, the feed port 257 and the thrust receptacle part 44c are arranged not to contact with each other.
As shown in
According to the second embodiment, lubricating oil as a lubricant supplied from the camshaft 1 is introduced into the driving rotor 40 from the feed port 257. Since the outer edge part 257a of the feed port 257 opposite from the contact surface 54a of the camshaft 1 is arranged on the radially inner side of the outer circumference part 1b of the journal portion 1a at least, lubricant easily infiltrates into the interface of the journal portion 1a by centrifugal force. Since the outer edge part 257a adjacent to the contact surface 54a is arranged on the radially outer side of the tip end 1d of the chamfering portion 1c, lubricating oil easily and smoothly infiltrates into the contact surface 54a and interface of the journal portion 1a. Thus, the valve timing controller 200 can be offered in which lubricating oil easily lubricates various parts.
According to the second embodiment, the outer edge part 257a on the opposite side is arranged on the radially inner side of the outer circumference part 1b of the journal portion 1a, and is arranged on the radially inner side of the tip end 1d of the chamfering portion 1c. Accordingly, lubricating oil can be made to infiltrate into various parts by centrifugal force from the radially inner side.
According to the second embodiment, the outer edge part 257a adjacent to the contact surface 54a of the camshaft 1 is arranged on the radially outer side of the tip end 1d of the chamfering portion 1c, and is arranged on the radially inner side of the outer circumference part 1b of the journal portion 1a. Accordingly, lubricating oil infiltrates into the interface of the journal portion 1a more easily by centrifugal force from the outer edge part 257a adjacent to the contact surface 54a of the camshaft 1.
According to the second embodiment, the diameter of the feed port 257 is decreased at the outer edge part 257a stepwise extending away from the contact surface 54a. Accordingly, the step produces a liquid pool at the feed port 257, and lubricating oil easily infiltrates into the interface of the journal portion 1a with centrifugal force from the liquid pool.
According to the second embodiment, the driven rotor 50 has the pressure regulation hole 251 releasing the pressure of lubricating oil between the driven rotor 50 and the driving rotor 40 on the radially outer side of the feed port 257. Accordingly, the driving rotor 40 is restricted from being displaced relative to the driven rotor 50 due to the pressure of lubricating oil between the driven rotor 50 and the driving rotor 40. As a result, motion of the planet gear 70 is restricted from being affected.
The advantage of the first embodiment is also acquired by the composition which is common between the first embodiment and the second embodiment.
As a first modification of the first and second embodiments, the feed port 57 may be established at two or more places.
As a second modification of the second embodiment, the outer edge part 257a on the opposite side may be arranged on the radially inner side of the outer circumference part 1b of the journal portion 1a, and the outer edge part 257a adjacent to the contact surface 54a may be arranged on the radially outer side of the tip end 1d of the chamfering portion 1c.
For example, as shown in
For example, as shown in
For example, as shown in
As a third modification of the second embodiment, as shown in
As a fourth modification of the first and second embodiments, the driving rotor 40 may not have the thrust receptacle part 44c.
As a fifth modification of the first and second embodiments, the driving rotor 40 may not have the pressure regulation hole 44d, and/or the driven rotor 50 may not have the pressure regulation hole 251.
The present disclosure is applicable to an equipment which adjusts valve timing of an exhaust valve or an equipment which adjusts valve timing of both an intake valve and an exhaust valve.
Such changes and modifications are to be understood as being within the scope of the present disclosure as defined by the appended claims.
Number | Date | Country | Kind |
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2014-209565 | Oct 2014 | JP | national |