Abstract: A roller bearing includes an outer ring formed by connecting a plurality of arc-shaped outer ring members in a circumferential direction and a plurality of rollers arranged along an inner diameter surface of the outer ring. A slope surface (22i) is provided at one or each circumferential end on an inner diameter surface of the outer ring member (22a), and a contour line of the slope surface (22i) is along a direction perpendicular to a revolution direction of the roller.

Abstract: A variable valve lift device of an internal combustion engine having a first link arm rotatably supported at a fixed position of an engine body rotatably connected to a rocker arm, and a movable support shaft rotatably supporting one end portion of a second link arm of which an other end portion rotatably connected to the rocker arm is connected to a crank member formed in a crank shape having crank webs sandwiching the second link arm from opposite sides and a connecting part integrally joining both the crank webs at a position where interference with the second link arm is avoided. The crank member is rotationally driven with a drive device and an amount of lift of an engine valve is continuously changed, in addition to which, torsional rigidity of the crank member is ensured while ensuring assembly workability of the second link arm to the crank member, and reduction in size is made possible.

Abstract: In a variable stroke engine comprising a plurality of links (60, 61) connecting a piston (11) with a crankshaft (30), a control member (65) disposed on an engine main body so as to be moveable in two directions over a prescribed range relative to the engine main body, a control link (63) connecting one of the plurality of links with the control member and an actuator (AC) for displacing the control member, the actuator comprises a ratchet mechanism that utilizes a force transmitted from the piston to the control member as an actuating force for the control member. By providing a spring member (73, SP, 121) that applies a biasing force to the control member, an appropriate actuating force can be applied to the control member in either direction.

Abstract: A rocker arm (63) is provided with a valve connecting portion (63a) into which tappet screws (70) abutting against a pair of engine valves (19) are screwed so that their advance/retract positions can be adjusted, and the rocker arm (63) has a cam abutting portion (65) which abuts against a valve operating cam (69) and is interlocked and connected to the engine valves (19). The rocker arm (63) turnably connects to one end of a first link arm (61) turnably supported at a fixed position of an engine body and to one end of a second link arm turnably supported by a displaceable movable support shaft (68a). The rocker arm (63) is formed so that the valve connecting portion (63a) has a larger width in a direction along a rotating axis of the valve operating cam (69) than in the remaining part. This enables the lift amount of the engine valves to be continuously varied. It is also possible to reduce the size of the system, while ensuring follow-up ability of the opening/closing operations.

Abstract: There is provided an intake air amount control system for an internal combustion engine, which controls the amount of intake air by executing both cam phase control and valve lift control, and is capable of enhancing response and accuracy of the intake air amount control, while avoiding interaction between the cam phase control and the valve lift control. In the intake air amount control system 1, an ECU 2 controls the amount of intake air according to a target valve lift Liftin_cmd and a target cam phase Cain_cmd. The Liftin_cmd and Cain_cmd are respectively calculated as the sums of master values Liftin_cmd_ms and Cain_cmd_ms for causing an actual intake air amount Gcyl to converge to a target intake air amount Gcyl_cmd, and slave values Liftin_cmd_sl and Cain_cmd_sl set according to the master values Liftin_cmd_ms and Cain_cmd_ms (steps 56 and 64).

Abstract: An engine valve operating system is provided in which one end of a first link arm (61) turnably supported at a fixed position of an engine body and the other end of a second link arm (62) turnably supported by a displaceable movable shaft (68a) are turnably connected to a rocker arm (63) which has a cam abutting portion (65) abutting against a valve operating cam (69) and is interlocked and connected so as to apply a force in a valve opening direction to an engine valve (19) biased by a valve spring (24) in a valve closing direction. A rocker arm biasing spring (54) which is different from the valve spring (24) biases the rocker arm (63) in a direction in which the cam abutting portion (65) abuts against the valve operating cam (69). This ensures follow-up ability of the opening/closing operations and enables a reduction in the size of the system, while allowing the lift amount of the engine valve to vary continuously.

Abstract: A needle roller bearing comprises an outer ring having a plurality of outer ring members split by a parting line extending in the axial direction of the bearing, a plurality of needle rollers rotatably arranged on the raceway surface of the outer ring, and a retainer retaining the plurality of needle rollers. A curvature radius r1 of the outer ring member and a curvature radius r2 of the outer diameter of the retainer has a relation such that 1<r1/r2<1.3.

Abstract: A needle roller bearing comprises an outer ring having a plurality of outer ring members split by a parting line extending in the axial direction of the bearing, and a plurality of needle rollers rotatably arranged on the raceway surface of the outer ring. Thus, a non-contact length “L” between the outer ring members and the needle roller at an abutment part of the adjacent outer ring members, and an effective length “w” of the needle roller has a relation such that L/w<0.5.

Abstract: In an engine having a cylinder head which forms a portion of an engine body and is provided with an intake valve operated for opening and closing operations by an intake valve operating device having an intake camshaft and an exhaust valve driven for opening and closing operations by an exhaust valve operating device having an exhaust camshaft, the intake camshaft (30) is placed higher in position than the exhaust camshaft (35) by increasing the distance between the intake camshaft (30) and a combustion chamber (17) along a cylinder axis (C) of the engine body (11) relative to that between the exhaust camshaft (35) and the combustion chamber (17). Lubricating oil is thereby enabled to be easily used for exhaust valve operating device after being used for lubrication and cooling of the intake valve operating device, thus achieving efficient lubrication and cooling of the exhaust valve operating device.

Abstract: An engine valve operating system is provided in which a rocker arm (63) linked and connected to an engine valve (19) and has a cam-abutting portion (65) to abut a valve operating cam (69) is turnably connected, via first and second connecting shafts (64, 66), to one end of a first link arm (61) turnably supported on an engine body (10) and one end of a second link arm (62) turnably supported by a displaceable movable shaft (68a). Also, oil supply means (58) which supply oil to the upper connecting shaft (64) of first and second connecting shafts (64, 66) are fixed to the engine body (10). This makes it possible to implement an engine valve operating system which is compact in size, ensures follow-up ability of the valve opening/closing operation, has a simple lubricating structure with a reduced number of parts, and ensures smooth valve operation while allowing the lift amount of the engine valve to be varied continuously.

Abstract: An engine valve operating system is provided in which a rocker arm that swings by following a valve operating cam abuts against an engine valve via a hydraulic tappet, a receiving member (41) receiving the hydraulic tappet (12) being slidably fitted into the rocker arm (13), the hydraulic tappet (12) being fitted into the rocker arm (13), a restricting part (29) being provided so as to face the receiving member (41) from the side opposite to the hydraulic tappet (12), and an adjustment screw (44) for adjusting a clearance between the restricting part (29) and the receiving member (41) when the engine valve is in a valve-closed state being screwed into an engine main body (5) so that its position can be adjusted back-and-forth so as to abut against the receiving member (41) when the engine valve is closed.

Abstract: A variable valve lift device of an internal combustion engine is provided in which a first link arm (58) rotatably supported at a fixed position of an engine body is rotatably connected to a rocker arm (31), and a movable support shaft (60) rotatably supporting one end portion of a second link arm (59) of which other end portion rotatably connected to the rocker arm (31) is connected to a crank member (61) formed in a crank shape having crank webs (61a) sandwiching the second link arm (59) from opposite sides, and a connecting part (61c) integrally joining both the crank webs (61a) at a position where interference with the second link arm (59) is avoided. The crank member (61) is rotationally driven with drive means. Thus, an amount of lift of an engine valve is continuously changed, in addition to which, torsional rigidity of the crank member is ensured while ensuring assembly workability of the second link arm to the crank member, and reduction in size is made possible.

Abstract: In an engine in which a lift amount of a valve can be changed continuously, an engine valve operating system including a valve lift-changing mechanism is capable of increasing and decreasing the lift amount of the valve without changing an opening angle for the valve and capable of decreasing a tappet clearance in accordance with a decrease in lift amount of the valve. Thus, it is possible to prevent the ratio of the tappet clearance to the lift amount at a low valve lift from being increased to minimize the influence of the dispersion of the tappet clearance and to reduce the seating speed of the valve at the low valve lift to prevent the generation of a noise. It is also possible to prevent a reduction in performance of the engine at a high valve lift due to the dispersion of the tappet clearance and to decrease the seating noise of the valve at the low valve lift.

Abstract: A valve-operating system for an internal combustion engine includes cam followers which have cam abutment portions abutting against valve-operating cams provided on a camshaft and which are swingably carried in an engine body and operatively connected to engine valves biased in a closing direction by a valve spring. The cam followers are biased in a direction of abutment of the cam abutment portions against the valve-operating cams by a resilient biasing means different from the valve spring. A resilient biasing means includes a pull rod connected at one end thereof to the cam follower, and a compression coil spring interposed between the other end of the pull rod and the engine body to pull the pull rod to bias the cam follower in a direction of abutment of the cam abutment portion against the valve-operating cam. Thus, the resilient biasing means is constructed to be compact, leading to an increase in degree of freedom of the design of the structure of the valve-operating system.

Abstract: An engine valve operating system is provided in which one end of a first link arm (61) turnably supported at a fixed position of an engine body and the other end of a second link arm (62) turnably supported by a displaceable movable shaft (68a) are turnably connected to a rocker arm (63) which has a cam abutting portion (65) abutting against a valve operating cam (69) and is interlocked and connected so as to apply a force in a valve opening direction to an engine valve (19) biased by a valve spring (24) in a valve closing direction. A rocker arm biasing spring (54) which is different from the valve spring (24) biases the rocker arm (63) in a direction in which the cam abutting portion (65) abuts against the valve operating cam (69). This ensures follow-up ability of the opening/closing operations and enables a reduction in the size of the system, while allowing the lift amount of the engine valve to vary continuously.

Abstract: A rocker arm (63) is provided with a valve connecting portion (63a) into which tappet screws (70) abutting against a pair of engine valves (19) are screwed so that their advance/retract positions can be adjusted, and the rocker arm (63) has a cam abutting portion (65) which abuts against a valve operating cam (69) and is interlocked and connected to the engine valves (19). The rocker arm (63) turnably connects to one end of a first link arm (61) turnably supported at a fixed position of an engine body and to one end of a second link arm turnably supported by a displaceable movable support shaft (68a). The rocker arm (63) is formed so that the valve connecting portion (63a) has a larger width in a direction along a rotating axis of the valve operating cam (69) than in the remaining part. This enables the lift amount of the engine valves to be continuously varied. It is also possible to reduce the size of the system, while ensuring follow-up ability of the opening/closing operations.

Abstract: An engine valve operating system is provided that includes a variable valve lift mechanism in which, when there is a possibility that the rotational speed of the engine might increase beyond an allowed rotational speed due to a downshift error in a manual transmission, etc., the amount of valve lift is decreased without changing the opening angle of the valve (19). By so doing, the curvature at the top of the curve of lift of the valve (19) is reduced, the inertial force applied to the valve (19) is reduced, and improper movement of the valve (19) can be prevented. Moreover, it is possible to prevent any increase in the intake air volume due to a decrease in the amount of lift of the valve (19), and prevent the effectiveness of engine braking from being degraded, thus enabling the rotational speed of the engine to be decreased and thereby preventing improper movement of the valve (19) from being promoted.

Abstract: A pair of link arms each supported at one end thereof on an engine body for swinging movement about an axis parallel to a rotational axis for a valve-operating cam are connected at the other ends, for relative turning movement about an axis parallel to the rotational axis, directly to a rocker arm having a valve abutment abutting against an engine valve and a cam abutment contacting with the valve-operating cam. At least any one of the link arms is swingably supported at one end thereof on the engine body for continuous movement within a plane perpendicular to a rotational axis for the valve-operating cam. Such an arrangement ensures that a valve-operating system can be constructed compactly, and the opening lift amount of the engine valve can be changed continuously, while ensuring an excellent followability to the valve-operating cam.

Abstract: A needle roller bearing comprises an outer ring having a split part in a circumferential direction, a plurality of rollers which can roll along an inner diameter surface of the outer ring, and a cage holding the plurality of rollers. The outer ring has an engaging click protruding inward along a diameter at a width-direction end thereof to prevent the cage from moving in an axial direction.

Abstract: A needle roller bearing comprises an outer ring having a plurality of outer ring members split by split lines extending in an axial direction of the bearing, a plurality of needle rollers arranged on an orbit surface of said outer ring so that they can roll thereon, and a cage holding the needle rollers at intervals. The outer ring member has a projection serving as a positioning engaging part which engages with a housing for positioning, and an engaging click protruding from an axial end of the outer ring member inward along a diameter to prevent the cage from moving in an axial direction, in positions shifted from its circumferential center.