公开(公告)号：JPH11210423A

公开(公告)日：1999-08-03

申请号：JP1754898

申请日：1998-01-29

Applicant: MAZDA MOTOR

Inventor： ASAI AKIRA ,  DEGUCHI HIROAKI

IPC: F01L1/34

Abstract: PROBLEM TO BE SOLVED: To efficiently prevent damage to a camshaft without enlarging the axial diameter of the camshaft. SOLUTION: In this valve system for an engine equipped with a camshaft 1 driving the intake valve or exhaust valve of the engine, a plurality of oil passages 9, 10 is formed, which extends from the journal part 1b of the camshaft 1 supported by a bearing member comprising a cam cap 4 to the end part side of the camshaft 1, and also this plurality of oil passages 9, 10 is arranged in a position that it may not be overlapped on the projected part 14 of a cam profile when viewed from the end part side of the camshaft 1.

公开(公告)号：JPH11132016A

公开(公告)日：1999-05-18

申请号：JP31607897

申请日：1997-10-30

Applicant: MAZDA MOTOR

Inventor： DEGUCHI HIROAKI ,  ASAI AKIRA ,  ITO KAZUTOSHI

IPC: F01L1/34 ,  F02F7/00

Abstract: PROBLEM TO BE SOLVED: To make a device compact by forming an opening part in the upper wall of a cylinder head cover, and covering the opening part from the upper face side of the cylinder head cover with a valve case housing an oil control valve. SOLUTION: In a variable valve timing device of an internal combustion engine, which is provided with a valve timing adjusting mechanism 4 for adjusting the valve operating timing, and an oil control valve 12 provided in an oil path leading to the valve timing adjusting mechanism 4 to control oil pressure to adjust valve timing, an opening part 16 is formed in the upper wall of a cylinder head cover 1, the opening part 16 is covered from the upper face side of the cylinder head cover 1 with a valve case 11 in which the oil control valve 12 is housed, and oil paths 33 to 36 which utilize the opening part to connect the oil control valve 12 and the valve timing adjusting mechanism 4, are formed.

公开(公告)号：JPH0742511A

公开(公告)日：1995-02-10

申请号：JP20825293

申请日：1993-07-30

Applicant: MAZDA MOTOR

Inventor： ASAI AKIRA ,  NISHIDA MASAMI ,  FUKUMA MASANARI ,  DEGUCHI HIROAKI

IPC: F01L1/12 ,  F01L1/18

Abstract: PURPOSE:To set the sliding angle of a sliding cam to a low level so as to reduce abrasion resistance while attempting compatibility between improvement of rotary limit by ensuring rigidity of a swing arm and improvement of compact state by miniaturizing the sliding cam and the swing arm. CONSTITUTION:The valve system for an engine is provided with a swing arm 16 which abuts on the valve stem 5 upper end of an intake/exhaust valve 3 and lifts the intake/exhaust valve 3 by oscillating, an oscillating cam 14 for oscillating the swing arm 16 by being in sliding contact with the swing arm 16 and oscillating and a driving cam 12 for oscillating a swing cam 14 by coming in sliding contact with the oscillating cam 14 and oscillating. The lever ratio of the swing arm 16 is set so as to be changed for a period from closing valve to opening valve between the level of 1.0 or less at the time of a base circle and the level of 1.0 or more at the time of max lift, around 1.0 which is the center of levels.

公开(公告)号：JPH0726920A

公开(公告)日：1995-01-27

申请号：JP19403193

申请日：1993-07-09

Applicant: MAZDA MOTOR

Inventor： FUKUMA MASANARI ,  DEGUCHI HIROAKI ,  NISHIDA MASAMI ,  ASAI AKIRA

IPC: F01L13/00 ,  F02D11/06

Abstract: PURPOSE:To shorten the overall length of a cylinder head in which cam shaft shifting means is incorporated, and to restrain occurrence of knocking sound caused by variation in thrust. CONSTITUTION:An engine valve timing control device comprises a cam shaft 1 having an axially tapered cam 3, and cam shaft shifting means 4 for axially shifting the cam shaft 1 so as to change the valve lift. Further, the cam shaft shifting means 4 comprises a cylinder member 25 constituting a double-acting hydraulic cylinder, a piston member 26 inserted in the cylinder member 25 so as to reciprocate in the direction of the cam shaft, and a thrust limiting member 30 integrally incorporated with the piston member 26 and locked to an end part of the cam shaft so as to limit the movement of the cam shaft 1 in the thrust direction. Further, a thrust limiting member 30 is located in a hydraulic chamber 27 in the cylinder part 25, and the cylinder member 25 defines therein a bearing part 34 for the cam shaft end part.

公开(公告)号：JPH0726918A

公开(公告)日：1995-01-27

申请号：JP19402993

申请日：1993-07-09

Applicant: MAZDA MOTOR

Inventor： NISHIDA MASAMI ,  DEGUCHI HIROAKI ,  FUKUMA MASANARI ,  ASAI AKIRA

IPC: F01L1/08 ,  F01L1/12 ,  F01L1/18 ,  F01L13/00

Abstract: PURPOSE:To ensure rigidity without the installation of an additional rib and to reduce an inertia weight so as to enhance the speed limitation by setting the width of the cam surface of a swingable cam, narrower than that of the follower surface thereof so that the cam surface can be used as a reinforcing rib. CONSTITUTION:In an engine cam drive system, a swingable cam 9 has a cam surface 12 which makes slidable contact with an intake and exhaust valve 4 through the intermediary of either one 3 of movable members, that is, a tappet and a swing arm, and a follower surface 11 which makes slidable contact with a cam 7 on a cam shaft 2, and the follower surface 11 of the swingable cam 9 and the slidable contact surface of the cam 7 are tapered toward the cam shaft 6 so that the valve timing is changed by relatively moving the cam shaft 6 in the direction thereof. Further, the cam surface 12 of the swingable cam 9 has a narrow width so that the cam surface 12 serves as a rib 13, while the width of the follower surface 11 is set to be wider than the cam surface 12.

公开(公告)号：JPH06272525A

公开(公告)日：1994-09-27

申请号：JP6417793

申请日：1993-03-23

Applicant: MAZDA MOTOR

Inventor： FUKUMA MASANARI ,  NISHIDA MASAMI ,  ASAI AKIRA

IPC: F01L1/08 ,  F01L13/00

Abstract: PURPOSE:To maintain favourable output performance by setting cam surfaces of driving cams and oscillating cams so that composite acceleration of valve lift before and after variable operation of valve timing. CONSTITUTION:Shapes of cam surfaces 7a, 8a of driving cams 7, 8 and cam surfaces 41, 51 of oscillating cams 4, 5 are set so that a positive acceleration compound on the cam surfaces 41, 51 of the oscillating cams 4, 5 and a positive acceleration compound on the cam surfaces 7a, 8a of the driving cams 7, 8 are not overlapped in a valve lift process and the positive acceleration compound of the driving cams 7, 8 precede the positive acceleration compound of the oscillating cams 4, 5. Consequently, change of valve lift acceleration before and after variation at the time of valve timing variation by way of moving a camshaft 6 in the axial direction and change to the side of reduction are restrained. Accordingly, it is possible to maintain favourable output performance without lowering of engine output.

公开(公告)号：JPH0617627A

公开(公告)日：1994-01-25

申请号：JP17712792

申请日：1992-07-03

Applicant: MAZDA MOTOR

Inventor： ASAI AKIRA ,  NISHIDA MASAMI ,  FUKUMA MASANARI

IPC: F01L1/10 ,  F01L1/12 ,  F01L1/26 ,  F01L13/00

Abstract: PURPOSE:To reduce the number of slidable contact parts necessary to oscillate an oscillating cam to lift an intake valve or an exhaust valve of an engine and to obtain the satisfactory amount of the lift of the intake or exhaust valve. CONSTITUTION:A crank member 16 is rotated following a driving cam shaft 14. The crank member 16 is connected to an oscillating cam 12 by a crank arm 17. When a cylindrical member 15 mounted on the driving cam shaft 14 in a rotatable manner is rotated, the connection part of the cylindrical member 15 to a link member 18 is moved along a circular hole part 116b, and the upper end part of the crank arm 17 is moved along an oblong hole l6a. Thus, the radius of rotation of the connection part of the crank member 16 to the crank arm 17 is changed, and the opening/closing timing of an intake/exhaust valve 10 is changed.

公开(公告)号：JP2004245074A

公开(公告)日：2004-09-02

申请号：JP2003033413

申请日：2003-02-12

Applicant: Mazda Motor Corp ,  マツダ株式会社

Inventor： ASAI AKIRA

IPC: F01L1/34 ,  F01L13/00

Abstract: PROBLEM TO BE SOLVED: To form a compact cam cap by integrating a cam journal lubricating oil passage and a lock pin releasing oil passage for common use, and to provide a variable valve gear for an engine having a compatibility of engine starting stability and lubricating performance.
SOLUTION: The valve gear has: a first control circuit 90 including first control valves 23 and 24 to supply and discharge working oil to and from a phase variable mechanism; and a second control circuit 110 including a second control valve 120 to supply and discharge working oil to and from a lock releasing chamber 54. An oil passage 123 inside a cam shaft in the second control circuit 110 is branched and communicated to a bearing lubricating oil passage 124 provided inside the cam shaft. A control means 113 to control opening and closing, and an opening degree of the second control valve 120 is provided, and the control means 113 open-controls the opening degree of the second control valve 120 into a throttling state until complete explosion at least when the engine is started.
COPYRIGHT: (C)2004,JPO&NCIPI

公开(公告)号：JP2004239164A

公开(公告)日：2004-08-26

申请号：JP2003029290

申请日：2003-02-06

Applicant: Mazda Motor Corp ,  マツダ株式会社

Inventor： ASAI AKIRA

IPC: F01L1/04 ,  F01L1/34

Abstract: PROBLEM TO BE SOLVED: To provide a variable valve system for an engine with good responsiveness and small overlapping when an accelerator is returned from a high load condition to a low/medium load condition.
SOLUTION: In this variable valve system, portions of an advancing hydraulic line and a retarding hydraulic line for intake respectively comprise annular grooves 104, 113 for advancing and retarding provided on a bearing surface 4a for an intake camshaft 5 of a cam cap 4 that supports the camshaft 5 and a camshaft 6; and portions of an advancing hydraulic line and a retarding hydraulic line for exhaust respectively comprise annular grooves 123, 133 for advancing and retarding provided on a bearing surface 4b for the exhaust camshaft 6 of the cam cap 4. The annular groove 113 for retarding on the bearing surface 4a for the intake camshaft 5 of the cam cap 4 and the annular groove 123 for advancing on the bearing surface 4b for the exhaust camshaft 6 of the cam cap 4 are respectively provided in the center in the width direction of their respective bearing surfaces 4a, 4b.
COPYRIGHT: (C)2004,JPO&NCIPI

公开(公告)号：JPH11280414A

公开(公告)日：1999-10-12

申请号：JP8668198

申请日：1998-03-31

Applicant: Mazda Motor Corp ,  マツダ株式会社

Inventor： ASAI AKIRA ,  ARAKI KEIJI

IPC: F02B67/06 ,  F01L1/04 ,  F01L1/18 ,  F01L1/26 ,  F01L1/34 ,  F02F1/42

Abstract: PROBLEM TO BE SOLVED: To improve reliability without causing a considerable rise of a produc tion cost or useless increase in an engine overall length, by reducing a load applied to mainly NO.1 journal and bearing part of a cam shaft, in a narrow angle type DOHC engine E equipped with VVT for rotating a cam shaft relative ly to a cam pulley, to change the opening/closing timing of a valve to make output improvement and fuel cost reduction, etc., compatible, and having the narrow nipping angle of an exhaust valve. SOLUTION: Two cam shafts 2 and 3 on suction and exhaust sides are arranged close to each other in an engine width direction, so as to overlap on the center line looking from the center line direction of the head bolt holes 20 and 20... of a cylinder head 1. The cam shaft 2 on the suction side arranged with VVT is adopted as a loose side cam shaft having a cam pulley into which the loose side span of a timing belt enters.

Abstract translation: 要解决的问题：为了提高可靠性，而不会导致生产成本的显着提高或发动机总长度的无用增加，通过减小主要以NO.1轴颈和凸轮轴的轴承部分施加的负载，以窄角度 配有VVT的DOHC发动机E，用于相对于凸轮滑轮旋转凸轮轴，以改变阀的打开/关闭正时，使输出改善和燃料成本降低等，并且具有窄的夹角 排气阀。 解决方案：吸气侧和排气侧的两个凸轮轴2和3沿发动机宽度方向彼此靠近设置，以便在头螺栓孔20和20的中心线方向上与中心线重叠。 采用配置有VVT的吸入侧的凸轮轴2作为具有凸轮滑轮的松弛侧凸轮轴，同步带的松散侧跨距进入该凸轮滑轮。