JPH04119311U - Camshaft lubrication system for overhead camshaft type engines - Google Patents

Abstract

(57) [Summary] [Purpose] When lubricating oil is supplied to the bearing parts 9, 10 of the camshafts 5, 7 and the hydraulic chain tension mechanism 15 for the timing chain 14 in an overhead camshaft type engine, The configuration is such that the supply of lubricating oil to the bearing parts 9 and 10 is not inhibited,
Simplify. [Structure] A hydraulic pressure supply passage 21 to the hydraulic chain tension mechanism 15 is formed inside the cylinder head 2, and this hydraulic pressure supply passage 21 is connected to the lubricating oil supply passages 19, 20 to the bearing parts 9, 10. It is connected to a portion close to the opening for the bearing portions 9 and 10.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

The present invention is a so-called oil cylinder with a camshaft installed on the top surface of the cylinder head. - In a bar head camshaft type engine, the bearing portion of the camshaft In addition to supplying lubricating oil to the camshaft, the timing from the crankshaft to the camshaft To supply hydraulic pressure to the hydraulic chain tension mechanism for the chain. The invention relates to a lubricating device.

0002

[Conventional technology]

Generally, in an overhead camshaft type engine, from the crankshaft A timing chain is used to transmit power to the camshaft, which is an improvement over prior technology. Japanese Utility Model Application Publication No. 57-71711 discloses a method for maintaining the timing chain in a tensioned state. A hydraulic chain tension mechanism is used to hold the This hydraulic chain tension mechanism is used for various operating parts in the engine. It is proposed to supply some of the lubricating oil.

0003

[Problem that the idea aims to solve]

However, this prior art does not provide the hydraulic chain tension from the lubricating oil pump. The hydraulic pressure supply pipe to the engine mechanism is formed inside the cylinder block or cylinder head. The lubricating oil supply passage is configured to be provided outside the engine separately from the lubricating oil supply passage. Therefore, not only does the structure become more complex and the price increase significantly, but also the lubrication This increases the number of locations where oil can leak, and what's more, the hydraulic valve is located outside the engine. It is necessary to secure enough space to install the hydraulic pressure supply line to the tension mechanism. Therefore, there is a problem that the engine becomes larger and heavier. Ta.

0004 The present invention provides a hydraulic chain tension mechanism for the timing chain. It is installed near the camshaft in the cylinder head, and A lubricating oil supply passage to the camshaft is formed inside the cylinder head. Focusing on the fact that the lubricant is supplied to the camshaft, Hydraulic chain tension without interfering with the supply of lubricant to the camshaft. The technical challenge is to solve the above problem by supplying hydraulic pressure to the mechanism. It is something that

[0005]

[Means to solve the problem]

In order to achieve this technical problem, this invention has a cylinder head with a camshaft. , hydraulic chain tension for the timing chain for power transmission to the camshaft. The lubricating oil pump is provided with a lubricating oil pump inside the cylinder head. An overhead cam with a lubricating oil supply passage to the bearing of the camshaft. In a shaft type engine, the hydraulic pressure supply communication to the hydraulic chain tension mechanism is a passage is formed inside the cylinder head, and the oil pressure supply passage is connected to the lubricating oil. The supply passage is connected to a portion of the supply passage close to the opening for the bearing portion.

[0006]

[Actions and effects of the idea]

With this configuration, the camshaft bearing is attached to the hydraulic chain tension mechanism. Hydraulic pressure can be supplied through the lubricating oil supply passage to the above-mentioned prior art. Install the hydraulic supply line for the hydraulic chain tension mechanism on the outside of the engine. This can be omitted.

[0007] In this case, the hydraulic pressure supply passage to the hydraulic chain tension mechanism is The lubricating oil supply passage to the shaft bearing is close to the opening to the bearing. When starting the engine, the lubricating oil pump is connected to the lubricating oil pump. The lubricating oil sent into the supply passage is transferred to the camshaft bearing and the hydraulic chain The hydraulic pressure can be supplied to both the hydraulic pressure and the hydraulic pressure mechanism at the same time. Camshaft bearing for supplying hydraulic pressure to the chain tension mechanism It is possible to reliably prevent delays and shortages in the supply of lubricating oil to parts. It is.

[0008]

[Effect of the idea]

Therefore, according to the present invention, when supplying lubricating oil to the hydraulic chain tension mechanism, In this case, the engine becomes larger and heavier, and lubricating oil leaks. This will definitely avoid an increase in the number of locations and an increase in prices. Furthermore, when starting the engine, lubricating oil is supplied to the camshaft bearing. said hydraulic chain tensioner without any delay or shortage in supply. It has the effect of supplying lubricating oil to the mechanism.

[0009]

【Example】

Hereinafter, embodiments of the present invention will be described below. The drawings when applied to an HC type engine will be explained. In the figure, numeral 1 indicates a cylinder block, and numeral 2 indicates the cylinder block 1. Each cylinder head is shown with a sealing gasket 3 sandwiched between them, and the corresponding The cylinder head 2 is attached to the cylinder block 1 with a plurality of head bolts 4. It has been concluded.

0010 Reference numeral 5 indicates a camshaft for the intake valve 6, and reference numeral 7 indicates a camshaft for the exhaust valve 8. Both camshafts 5 and 7 are connected to the cylinder head 2. are supported by bearings 9 and 10 parallel to each other on the upper surface thereof, and mesh with each other. They are interlocked by gears 11 and 12. In addition, the exhaust valve camshaft 8 is fitted with a A timing chain 14 is wound around the sprocket 13.

[0011] Reference numeral 15 denotes a hydraulic chain tensioner attached to the side surface of the cylinder head 2. As shown in FIG. 5, the hydraulic chain tension mechanism 15 is 15a, a plunger 15b slidably inserted into the case 15a, and the plunger 15b. It consists of a shoe member 15c attached to the tip of the plunger 15b, and its hydraulic chamber 15d. The spring 15e provided in the hydraulic chamber 15d and the hydraulic pressure introduced into the hydraulic chamber 15d Push out the plunger 15b and release the shoe member 15c at the tip of the plunger 15b. , by pressing against the timing chain 14, the timing chain 1 4, and its plunger 15b is designed to prevent its retreat. ratchet 15f is engaged.

0012 Further, reference numeral 16 indicates a lubricating oil pump (not shown) attached to the cylinder block 1. This lubricating oil passage 16 is bored in the gasket 3. The head bolt 4 communicates with the bolt hole 18 through which the head bolt 4 passes through the through hole 17. There is. The cylinder head 2 has the bolt hole 18 and the exhaust valve cam. A first lubricating oil supply passage 19 communicating with the shaft bearing part 10 is bored. and a portion of the first lubricating oil supply passage 19 near the bearing portion 10; a second lubricating oil supply passage communicating with the bearing portion 9 for the intake valve camshaft 5; A channel 20 is drilled. Furthermore, the cylinder head 2 includes the second lubricating oil supply passage. 20 near the bearing portion 9 and the hydraulic chain tension mechanism 15. A hydraulic pressure supply passage 21 communicating with the pressure chamber 15d is bored.

[0013] In this configuration, the lubricating oil passage in the cylinder block 1 from the lubricating oil pump The lubricating oil discharged into 16 reaches the first lubricating oil supply passage 19 through the bolt hole 18. The bearing of the exhaust valve camshaft 7 is supplied via this first lubricating oil supply passage 19. While some lubricating oil is supplied to the second lubricating oil supply passage 20, The oil flows into the bearing portion of the intake valve camshaft 5 from this second lubricating oil supply passage 20. 9 and the hydraulic chain tension via a hydraulic supply passage 21. It is supplied to the pressure chamber 15d in the mechanism 15.

[0014] In this case, a portion of the first lubricating oil supply passage 19 near the bearing portion 10 , while connecting the second lubricating oil supply passage 20 , while connecting the second lubricating oil supply passage 20 . By connecting the hydraulic pressure supply passage 21 to the part near the bearing part 9, it is possible to start the engine easily. During the movement, the lubricating oil supplied to the first lubricating oil supply passage 19 is transferred to the bearing portion 10. and the second lubricating oil supply passage 20 at the same time, while the second lubricating oil The lubricating oil that has entered the supply passage 20 is applied to both the bearing portion 9 and the hydraulic pressure supply passage 21 in approximately the same manner. Since lubricating oil can be distributed at the same time, there is no delay in supplying lubricating oil to both bearings 9 and 10. Therefore, it is possible to reliably reduce the occurrence of supply shortages or supply shortages.

[Brief explanation of drawings]

FIG. 1 is a plan view showing an embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II in FIG. 1;

FIG. 3 is a sectional view taken along line III-III in FIG. 1;

FIG. 4 is a sectional view taken along line IV-IV in FIG. 1;

FIG. 5 is a longitudinal sectional front view of the hydraulic chain tension mechanism.

[Explanation of symbols]

1 cylinder block 2 Cylinder head 3 Gasket 4 Head bolt 5 Camshaft for intake valve 7 Camshaft for exhaust valve 9,10 Bearing part 13 Sprocket 14 Timing chain 15 Hydraulic chain tension mechanism 17 Lubricating oil passage 18 bolt hole 19, 20 Lubricating oil supply passage 21 Hydraulic supply passage

Claims (1)

[Scope of utility model registration request] 1. A cylinder head is provided with a hydraulic chain tension mechanism for a camshaft and a timing chain for transmitting power to the camshaft, and a bearing for the camshaft is provided inside the cylinder head from the lubricating oil pump. In the overhead camshaft engine, the hydraulic chain tension mechanism is provided with a lubricating oil supply passage to the cylinder head, and the hydraulic chain tension mechanism is provided with a lubricating oil supply passage to the cylinder head. A camshaft lubricating device for an overhead camshaft engine, characterized in that the supply passage is connected to a portion of the supply passage that is close to an opening for the bearing portion.