Abstract: A timing transmission mechanism (T2) in an engine is formed of a chain transmission system (C) that is formed from a drive sprocket (20) mounted on a crankshaft (4), a driven sprocket (25) mounted on a pump input shaft (24) of a high pressure fuel pump (P), and a chain (22) wound around the drive sprocket (20) and the driven sprocket (25); and a gear transmission system (G) that is formed from a drive gear (26) mounted on the pump input shaft (24) coaxially with the driven sprocket (25) and a driven gear (27) mounted on a camshaft (13b) and meshing with the drive gear (26). This enables a timing transmission mechanism to be provided that can increase the degree of freedom in layout of the high pressure fuel pump without causing any increase in the number of components, the weight, or the backlash.

Abstract: An oil communication passage (39b) is formed so as to run through a wall portion (39) separating an oil collector (41) and an oil drop hole (38) formed in an engine cylinder head (14), and oil that has collected in the oil collector (41) can therefore be guided to the oil drop hole (38) via the oil communication passage (39b). An oil supply passage (39c) and a retaining hole (39a) for retaining a hydraulic tappet (22), which is operated by oil supplied from the oil supply passage (39c), are formed in the wall portion (39) of the cylinder head (14), and the oil supply passage (39c) and the oil communication passage (39b) communicate with each other via the retaining hole (39a); therefore, even if part of the oil supplied from the oil supply passage (39c) to the hydraulic tappet (22) leaks into the retaining hole (39a), the oil can be discharged by utilizing the oil communication passage (39b).

Abstract: A timing transmission mechanism (T2) in an engine is formed of a chain transmission system (C) that is formed from a drive sprocket (20) mounted on a crankshaft (4), a driven sprocket (25) mounted on a pump input shaft (24) of a high pressure fuel pump (P), and a chain (22) wound around the drive sprocket (20) and the driven sprocket (25); and a gear transmission system (G) that is formed from a drive gear (26) mounted on the pump input shaft (24) coaxially with the driven sprocket (25) and a driven gear (27) mounted on a camshaft (13b) and meshing with the drive gear (26). This enables a timing transmission mechanism to be provided that can increase the degree of freedom in layout of the high pressure fuel pump without causing any increase in the number of components, the weight, or the backlash.

Abstract: An internal combustion engine has a camshaft holder 20 attached to a cylinder head 1, and two camshafts 11 and 12 are rotatably supported by the camshaft holder 20. A high-pressure pump 60 has a driving shaft 63 rotatively driven by the camshaft. An accessory holder 30 provided with a mounting seat 40 to which the high-pressure fuel pump 60 is attached is formed integrally with a lower camshaft holder 21 included in the camshaft holder 20. The mounting seat 40 is formed integrally with the accessory holder 30 and is provided with a through hole 41 in which the driving shaft 63 is received. Thus the cylinder head 1 is formed in a small size and a light weight. The accessory holder 30 can be formed with a high rigidity in a small size.

Abstract: An oil communication passage (39b) is formed so as to run through a wall portion (39) separating an oil collector (41) and an oil drop hole (38) formed in an engine cylinder head (14), and oil that has collected in the oil collector (41) can therefore be guided to the oil drop hole (38) via the oil communication passage (39b). An oil supply passage (39c) and a retaining hole (39a) for retaining a hydraulic tappet (22), which is operated by oil supplied from the oil supply passage (39c), are formed in the wall portion (39) of the cylinder head (14), and the oil supply passage (39c) and the oil communication passage (39b) communicate with each other via the retaining hole (39a); therefore, even if part of the oil supplied from the oil supply passage (39c) to the hydraulic tappet (22) leaks into the retaining hole (39a), the oil can be discharged by utilizing the oil communication passage (39b).

Abstract: An internal combustion engine has a camshaft holder 20 attached to a cylinder head 1, and two camshafts 11 and 12 are rotatably supported by the camshaft holder 20. A high-pressure pump 60 has a driving shaft 63 rotatively driven by the camshaft. An accessory holder 30 provided with a mounting seat 40 to which the high-pressure fuel pump 60 is attached is formed integrally with a lower camshaft holder 21 included in the camshaft holder 20. The mounting seat 40 is formed integrally with the accessory holder 30 and is provided with a through hole 41 in which the driving shaft 63 is received. Thus the cylinder head 1 is formed in a small size and a light weight. The accessory holder 30 can be formed with a high rigidity in a small size.