Phase controller and cam shaft phase controller for internal combustion engine

Abstract

A parallel guide portion as an integral structure of a sprocket and a vane, as well as a slant guide portion, are arranged alternately on the same circumference, with circumferential gaps being formed between said guide portion and the parallel guide portion, said guide portion having a shape such that the circumferential gaps become smaller in one axial direction of a cam shaft. Wedge members are disposed in the circumferential gaps respectively and are moved in one axial direction to fill up the circumferential gaps, thereby fixing the phase between the sprocket and the vane into a locked state. The wedge angle of each wedge member is set sufficiently small and, by utilizing varying torques acting on the cam shaft, said members are each moved and locked in one axial direction with a spring. Said members are actuated in an opposite axial direction with oil pressure to release the locked state, thereby permitting a phase angle control. By utilizing a varying torque acting on the cam shaft, the phase of the cam shaft is returned for itself to an intermediate position and is locked without looseness.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a sectional side view in an intermediate position unlocked state of a phase controller according to a first embodiment of the present invention, corresponding to a sectional view taken on line A-A in FIG. 2;

FIG. 2 is a cross sectional view taken on line B-B in FIG. 1;

FIG. 3 is a sectional side view in an intermediate position locked state of the phase controller of the first embodiment, corresponding to a sectional view taken on line C-C in FIG. 4;

FIG. 4 is a cross sectional view taken on line D-D in FIG. 3;

FIG. 5A to FIG. 5E comprise planarly developed sectional views of a circumference E in FIG. 2 or FIG. 4, illustrating intermediate position locking operations;

FIG. 6 is a sectional side view in an intermediate position unlocked state of a phase controller according to a second embodiment of the present invention, corresponding to a sectional view taken on line F-F in FIG. 7;

FIG. 7 is a cross sectional view taken on line G-G in FIG. 6;

FIG. 8 is a sectional side view in an intermediate position locked state of the phase controller of the second embodiment, corresponding to a sectional view taken on line H-H in FIG. 9;

FIG. 9 is a cross sectional view taken on line I-I in FIG. 8;

FIG. 10(A) and FIG. 10(B) comprise planarly developed sectional views of a circumference J in FIGS. 7 and 9, illustrating intermediate position locking operations;

FIG. 11 illustrates the shape of a slant guide alone which is a constituent part used in the second embodiment;

FIG. 12 illustrates the shape of a wedge member (3) alone which is a constituent part used in the second embodiment;

FIG. 13 illustrates the shape of an Oldham's coupling alone which is a constituent part used in the second embodiment;

FIG. 14 illustrates the shape of a parallel guide alone which is a constituent part used in the second embodiment;

FIG. 15 illustrates the shape of a thrust guide screw alone which is a constituent part used in the second embodiment;

FIG. 16 illustrates an outline of a conventional valve timing controller used in an automobile engine; and

FIG. 17 illustrates functions and effects attained by the conventional valve timing controller.

Claims

1. A phase controller having a first rotating member and a second rotating member adapted to be rotated through the first rotating member and controlling a phase angle as a relative rotational position between the first and second rotating members, the phase controller comprising: a first guide portion mounted so as to be relatively unrotatable to an upstream-side member in a power transfer path from the first rotating member to the second rotating member and a second guide portion mounted so as to be relatively unrotatable to a downstream-side member in the power transfer path, the first guide portion and the second guide portion being arranged alternately in the direction of a circumference at the same radial position;a first wedge member disposed between the first guide portion and the second guide portion in one circumferential direction of the first guide portion on the circumference and a second wedge member disposed between the first guide portion and the second guide portion in the other circumferential direction; andurging means that urge the first wedge member and the second wedge member in one axial direction simultaneously and drive means that move the first wedge member and the second wedge member in an opposite axial direction,wherein the first wedge member and the second wedge member are moved in the one axial direction by the urging means and the wedge members come into close contact with both the first and second guide portions in the one circumferential direction and in the other circumferential direction.

2. A phase controller having a first rotating member and a second rotating member adapted to be rotated through the first rotating member and controlling a phase angle as a relative rotational position between the first and second rotating members, the phase controller comprising: a first guide portion mounted unrotatably relative to the first rotating member and occupying a part on a circumference at a certain radial position;a second guide portion mounted unrotatably relative to the second rotating member and arranged alternately with the first guide portion in the direction of a circumference at the same radial position as the certain radial position;a first wedge member disposed between the first and second guide portions in one circumferential direction of the first guide portion on the circumference;a second wedge member disposed between the first and second guide portions in the other circumferential direction of the guide portion;urging means that urge the first and second wedge members in one axial direction simultaneously; anddrive means that move the first and second wedge members in an opposite axial direction,wherein the first and second wedge members are moved in the one axial direction into close contact with both the first and second guide portions by the urging means.

3. A phase controller according to claim 1, wherein the first and second guide portions each have a shape such that a circumferential gap between both the guide portions becomes smaller in the one axial direction, and the first and second wedge members disposed within the circumferential gap also each have a shape such that the circumferential size decreases in the one axial direction.

4. A phase controller according to claim 1, wherein the drive means that move the first and second wedge members in the opposite axial direction utilizes oil pressure as the driving force.

5. A phase controller according to claim 1, further comprising a plurality of oil chambers whose volumes increase or decrease in directions opposite to each other in interlock with a phase change between the first and second rotating members, the phase change being performed by controlling the feed and discharge of hydraulic oil to and from each of the oil chambers in a state in which the first and second wedge members are moved in the opposite axial direction by the drive means.

6. A phase controller according to claim 1, wherein the first and second wedge members comprise two or more pairs of first and second wedge members, and the first and second guide portions also comprise two or more pairs of first and second guide portions.

7. A phase controller according to claim 6, wherein the two or more pairs of the first and second guide portions perform a relative, translational motion in a plane orthogonal to the axial direction.

8. A phase controller according to claim 1, wherein a cutout portion is formed in at least one of the first guide portion and the second guide portion, the cutout portion corresponding to an axial position range which the first and second wedge members having been moved to one end in the opposite axial direction by the drive means occupy, and a circumferential gap between the first and second guide portions varies stepwise in the presence of the cutout portion.

9. A cam shaft phase controller for an internal combustion engine, comprising the phase controller described in claim 1, wherein the first rotating member is a rotating member rotated by a crank shaft of an engine and the second rotating member is a rotating member connected integrally with a cam shaft.

10. A valve timing controller for an internal combustion engine, comprising: a first rotating member to which a rotating force is transmitted from a crank shaft;a second rotating member configured to transmit a rotating force to a cam shaft;a phase shifting mechanism mounted so as to straddle the first and second rotating members and shifting a relative rotation phase of the cam shaft with respect to the crank shaft in accordance with the state of the internal combustion engine;contact/decontact portions adapted to move relatively in directions in which respective surfaces come into contact with or separate from each other in accordance with the shifting of the phase performed by the phase shifting mechanism, the distance between the surfaces varying in the axial direction of the first and second rotating members;a restraint member disposed so as to be movable between the surfaces of the contact/decontact portions and adapted to restrain the phase of the phase shifting mechanism at a predetermined position in a contacted state with the surfaces of the contact/decontact portions upon movement in one axial direction of the first and second rotating members and become spaced from at least one of the surfaces of the contact/non-contact portions to release the phase-restrained state of the phase shifting mechanism upon movement in the other axial direction; anda restraint control mechanism configured to cause the restraint member to move in accordance with the state of the internal combustion engine,wherein the restraint member is disposed so as to be positioned between the surfaces of the contact/decontact portions even in the phase-restraint released state of the phase shifting mechanism device.

11. A valve timing controller for an internal combustion engine, comprising: a first rotating member to which a rotating force is transmitted from a crank shaft;a second rotating member configured to transmit a rotating force to a cam shaft;a phase shifting mechanism mounted so as to straddle the first and second rotating members and shifting a relative rotation phase of the cam shaft with respect to the crank shaft in accordance with the state of the internal combustion engine;one or a plurality of moving portions each having a pair of end faces and provided in one member which moves relatively in accordance with the shifting of the phase performed by the phase shifting mechanism;a pair of restraint members disposed movably on both sides in the moving direction of the moving portion and adapted to, upon simultaneous movement thereof in one axial direction of the first and second rotating members, come into abutment under respective wedging actions against the pair of end faces, hold the moving body in a sandwiching manner and restrain the phase of the phase shifting mechanism at a predetermined position, while upon simultaneous movement thereof in the other axial direction of the first and second rotating members, separate from the pair of end faces to release the wedging actions, thereby releasing the restraint of the phase of the phase shifting mechanism; anda restraint control mechanism configured to cause the pair of restraint members to move in accordance with the state of the internal combustion engine,wherein the pair of restraint members are disposed so as to be kept opposed to at least one of the pair of end faces even in the phase-restraint released state of the phase shifting mechanism device.

12. A valve timing controller for an internal combustion engine, comprising: a first rotating member to which a rotating force is transmitted from a crank shaft;a second rotating member configured to transmit a rotating force to a cam shaft;a phase shifting mechanism mounted so as to straddle the first and second rotating members and shifting a relative rotation phase of the cam shaft with respect to the crank shaft in accordance with the state of the internal combustion engine;a restraint member adapted to move in one axial direction of the first and second rotating members, thereby restraining the phase of the phase shifting mechanism at a predetermined position, and move in the other axial direction of the first and second rotating members, thereby releasing the restraint of the phase of the phase shifting mechanism;a restraint control mechanism configured to cause the restraint member to move in accordance with the state of the internal combustion engine; andguide means that guide the restraint member up to the restraining position,wherein the restraint member is disposed so as to move always within the guide range of the guide means.

13. A phase controller according to claim 2, wherein the first and second guide portions each have a shape such that a circumferential gap between both the guide portions becomes smaller in the one axial direction, and the first and second wedge members disposed within the circumferential gap also each have a shape such that the circumferential size decreases in the one axial direction.

14. A phase controller according to claim 2, wherein the drive means that move the first and second wedge members in the opposite axial direction utilizes oil pressure as the driving force.

15. A phase controller according to claim 3, wherein the drive means that move the first and second wedge members in the opposite axial direction utilizes oil pressure as the driving force.

16. A phase controller according to claim 2, further comprising a plurality of oil chambers whose volumes increase or decrease in directions opposite to each other in interlock with a phase change between the first and second rotating members, the phase change being performed by controlling the feed and discharge of hydraulic oil to and from each of the oil chambers in a state in which the first and second wedge members are moved in the opposite axial direction by the drive means.

17. A phase controller according to claim 3, further comprising a plurality of oil chambers whose volumes increase or decrease in directions opposite to each other in interlock with a phase change between the first and second rotating members, the phase change being performed by controlling the feed and discharge of hydraulic oil to and from each of the oil chambers in a state in which the first and second wedge members are moved in the opposite axial direction by the drive means.

18. A phase controller according to claim 4, further comprising a plurality of oil chambers whose volumes increase or decrease in directions opposite to each other in interlock with a phase change between the first and second rotating members, the phase change being performed by controlling the feed and discharge of hydraulic oil to and from each of the oil chambers in a state in which the first and second wedge members are moved in the opposite axial direction by the drive means.

19. A phase controller according to claim 2, wherein the first and second wedge members comprise two or more pairs of first and second wedge members, and the first and second guide portions also comprise two or more pairs of first and second guide portions.

20. A phase controller according to claim 3, wherein the first and second wedge members comprise two or more pairs of first and second wedge members, and the first and second guide portions also comprise two or more pairs of first and second guide portions.