JPH0533689Y2 - - Google Patents

Description

[Detailed description of the invention] (Industrial application field) The present invention is a chain lubricating system for an engine, especially a V
The present invention relates to a lubricating device for a chain that drives each of the above camshafts in a type engine.

(Prior Art) The valve mechanism for a V-type engine has two banks arranged in a V-shape around the crankshaft. One shaft is disposed between both banks, and this camshaft is used to control the valve movement between both banks. The intake and exhaust valves of each cylinder are driven to open and close, and an overhead camshaft is installed at the top of each bank, and each camshaft drives the intake and exhaust valves of each cylinder in the bank. There is one that has been made. In either type of camshaft, the camshaft is rotationally driven by the crankshaft via a chain or belt that is wound between the camshaft and the crankshaft. An oil passage is required to lubricate the area around the sprocket and the sprocket.

By the way, according to Japanese Patent Application Laid-open No. 57-131808,
In a V-type engine in which one camshaft is disposed between both banks and the camshaft is driven by a crankshaft via a chain, a guide groove communicating with an oil pump discharge port is provided in a chain cover that covers the chain. In addition, the guide groove is provided with an ejection hole for ejecting oil toward the chain. According to this, since the oil passage for chain lubrication is provided using the chain cover, it becomes possible to lubricate the chain with a relatively simple structure without requiring complicated piping or the like.

(Problem that the invention aims to solve) However, in an overhead camshaft type V-type engine in which a camshaft is installed at the top of two banks, the camshaft is wound between these camshafts and the crankshaft. It is necessary to lubricate two chains, and therefore two systems of oil passages must be led from the oil pump or engine lubrication system, making the configuration and piping of the oil passages complicated, making workability and assembly difficult. Problems arise in terms of availability, cost, etc.

Therefore, the present invention aims to improve the rigidity of the chain case that houses both chains in an overhead camshaft type V-type engine in which camshafts that are driven via chains are disposed above the two banks. The present invention aims to make it possible to lubricate both chains most effectively with an oil passage having a simple structure, and to facilitate machining of this oil passage and reduce costs.

(Means for solving the problems) In order to achieve the above object, the engine lubrication device according to the present invention is characterized by being configured as follows.

That is, camshafts are respectively disposed in two banks arranged in a V-shape with the crankshaft at the center, and these camshafts are connected to the first and second drive sprockets fixed to the crankshaft by the above-mentioned crankshaft. In an engine configured to be driven through first and second chains respectively wound around sprockets, a built-up portion extending in a horizontal direction is formed in a chain case housing the chains at a position near the crankshaft. One oil hole communicating with the engine's lubrication system is drilled in this built-up part, and a first oil hole is injected into the oil hole toward predetermined positions of the first and second chains, respectively. , the second oil jet nozzles are provided at intervals in the horizontal direction.

(Function) According to the above configuration, oil is introduced from the engine lubrication system into the oil hole drilled in the chain case, and the oil is injected from the first and second oil jet nozzles. , the first and second chains wound between the crankshaft and each camshaft are lubricated. In that case, it is only necessary to provide one oil hole in the chain case, and by communicating this with the engine's lubrication system, two chains can be lubricated. The structure of the oil passage is significantly simplified, and the oil hole is horizontally bored in the chain case near the crankshaft, and the first and second oil holes are spaced apart from each other in the chain case. Since the jet nozzle is provided, it is possible to efficiently inject lubricating oil to the parts of the first and second chains that require the most lubrication, that is, the vicinity of the respective winding parts to the first and second drive sprockets. Become. And in the above chain case,
Since the built-up portion in which the oil hole is bored is formed, this built-up portion acts as a hollow rib, and the rigidity of the chain case is improved.

(Example) Examples of the present invention will be described below.

As shown in FIG. 1, a V-type engine to which an embodiment of the present invention is applied includes a cylinder block 1 and first and second cylinder heads 2 ₁ and 2 ₂ attached to the upper end of the block 1. It has first and second banks 4 1 and 4 ₂ arranged in a V-shape around the crankshaft ₃ , and each of these banks 4 ₁ and 4 ₂ has a plurality of cylinders (not shown). A pair of intake valve and exhaust valve camshafts 5 _{1 ,} 5 1 and 5 ₂ , 5 ₂ are provided in the first and second cylinder heads 2 1 , _{2 2} in a row, respectively. It is arranged parallel to the shaft 3. A first chain is connected between the first drive sprocket 6 ₁ fixed to the crankshaft 3 and the first driven sprockets 7 ₁ and 7 ₁ fixed to the camshafts 5 ₁ and 5 ₁ of the first bank 4 ₁ , respectively. 8 ₁ is wound around the second driving sprocket 6 ₂ (see FIG. 2) which is similarly fixed to the crankshaft 3, and a second driven sprocket 6 2 which is fixed to the camshafts 5 ₂ and 5 ₂ in the second bank 4 ₂ , respectively. A second chain 8 ₂ is wound between the sprockets 7 ₂ and 7 ₂ , and the camshafts 5 are connected to each other via these chains 8 ₁ and 8 ₂ .
₁ , 5 ₁ , 5 ₂ , 5 ₂ are connected by the crankshaft 3,
It is designed to be driven at half the rotation speed.

Here, the first and second driven sprockets 7 ₁ ,
7 ₁ , 7 ₂ , 7 ₂ and the upper halves of the first and second chains 8 ₁ , 8 ₂ are the ends of the cylinder heads 2 ₁ , 2 ₂ and the upper parts of these heads 2 ₁ , 2 _{2 .} It is housed in head covers 9 ₁ , _{9 2 that} cover it, and as shown in _{FIGS .} The half part is housed in a chain case 10 fixed to the end face of the cylinder block 1, and is covered by a chain cover 11 fixed to the case 10. Further, an oil pump 12 consisting of a pair of gears 12a, 12b and a cover 12c is housed around the penetration part of the crankshaft 3 on the back side of the chain case 10, and is directly driven by the crankshaft 3. There is.
In addition, in Figures 1 and 2, 13 is an oil pan installed at the bottom of the engine, and 14...14
are the fixed guides of the chains 8 ₁ and 8 ₂ , 15, 1
5 is also a movable guide, and these movable guides 15, 15 are chain tensioners 16, 16.
The chains 8 ₁ and 8 ₂ are biased in the direction of tension. Further, in FIG. 2, reference numeral 17 denotes a pulley fixed to the end of the crankshaft 3 that passes through the chain case 10 and cover 11, and a water pump (not shown) and a power generator are connected by a belt 18 wound around the pulley. The machine is now being driven.

However, as shown in FIGS. 2 to 4, there is a built-up part 10a extending in the horizontal direction at a position directly above the penetration part of the crankshaft 3 in the chain case 10.
An oil hole 20, which is a drill hole, is provided in the built-up portion 10a from one side. The open end of the oil hole 20 is closed by a plug 21, and the oil hole 20 is connected to the center of the chain case 10 from the back side.
A vertical communication hole 22 leading to the cylinder block 1 is bored, and an open end of the communication hole 22 is connected to an oil passage 1a opened in the end surface of the cylinder block 1.

Further, a boss portion 10b,
10b are provided at intervals in the horizontal direction, and first and second oil jet nozzles 23 ₁ and 23 ₂ are provided in these boss portions 10b and 10b so as to communicate with the oil holes 20 in the built-up portion 10a, respectively. It is fixed by press-fitting or the like and protrudes parallel to the crankshaft 3. And, in the protruding part of the first nozzle 23 ₁ ,
Nozzle holes 23a ₁ , 23a ₁ are formed in the first chain 8 ₁ to open toward a position near the part where the first drive sprocket 6 ₁ is wrapped, and the projecting portion of the second nozzle 23 ₂ is provided with the Nozzle holes 23a _{2 and 23a 2 are} provided that open toward a position near a portion of the second chain 8 ₂ where the second drive sprocket 6 ₂ is wrapped.

According to the above configuration, when the engine is operating, the crankshaft 3 connects the first drive sprocket 6 ₁ ,
The first chain 8 ₁ and the first driven sprocket 7 ₁ ,
The intake and exhaust valve camshafts 5 ₁ and 5 _{1 in the first bank 4 1 are rotationally} driven through the
Drive sprocket 6 ₂ , second chain 8 ₂ and second
Second bank 4 via driven sprockets 7 ₂ , 7 ₂
The intake and exhaust valve camshafts 5 ₂ and 5 ₂ in ₂ are rotationally driven.

Also, at this time, the oil discharged from the oil pump 12 is supplied to each part of the engine, and a portion of the oil is supplied to the chain case 10 from the oil passage 1a in the cylinder block 1 through the communication hole 22 provided in the chain case 10. First and second oil jet nozzles 23 ₁ , which are introduced into an oil hole 20 drilled laterally in the oil hole 20 and communicate with the oil hole 20 .
23 Flows into ₂ . Then, this oil flows through the nozzle holes 23a ₁ and 23 of the first oil jet nozzle 22.
As _shown by arrow _A in _{FIG . 2} and 23a ₂ to a position near the part where the second chain ₈₂ wraps around the second drive sprocket ₆₂ , as shown by arrow B in FIG. As a result, these chains 8 ₁ , 8 ₂
And these chains 8 ₁ , 8 ₂ and driving sprockets 6 ₁ , 6 ₂ or driven sprockets 7 ₁ , 7 ₁ ,
The wrapping portions between 7 ₂ and 7 ₂ will be lubricated.

In that case, since the first and second oil jet nozzles 23 ₁ and 23 ₂ are communicated with one oil hole 20 bored in the chain case 10,
Injection and supply of oil to the two chains 8 ₁ and 8 ₂ will be performed through one system of oil passages, and therefore the lubrication for the first and second chains 8 ₁ and 8 ₂ will be performed independently. Compared to the case where the oil passage is used, the configuration of the oil passage is significantly simplified. Further, the first and second oil jet nozzles 23 ₁ and 23 ₂ can be relatively freely arranged at any position of the built-up part 10a in the chain case 10, and in particular, these oil jet nozzles 23 ₁ and 23 ₂ are provided at intervals in the oil hole 20 extending horizontally at a position directly above the crankshaft 3, and the nozzle holes 23a ₁ and 23
Since the direction of a ₂ can be freely set, it is possible to inject and supply oil to the optimum positions of the chains 8 ₁ and 8 ₂ without interfering with the chains 8 ₁ and 8 ₂ . Furthermore, the oil hole 20 is
The built-up part 10a is drilled in the built-up part 10a provided in the chain case 10 and extends in the horizontal direction.
act as hollow ribs, thereby increasing the rigidity of the chain case 10, which is relatively thin overall.

(Effects of the invention) As described above, according to the invention, camshafts are arranged above the two banks arranged in a V-shape, and these camshafts are connected to the first bank, which is fixed to the shaft by the crankshaft. In an engine configured to be driven through a second drive sprocket and first and second chains respectively wound around these sprockets, a chain case housing the first and second chains is horizontally driven. A built-up part is formed that extends into the built-up part, and one oil hole that communicates with the engine's lubrication system is bored in this built-up part, and first and second oil jet nozzles are connected to the oil hole to communicate with the engine's lubrication system. are arranged at intervals in the horizontal direction, and oil is injected and supplied from these nozzles to the first and second chains, so that the two chains are lubricated by one system of oil using the chain case. This will be done through a passageway. As a result, compared to the case where each chain is lubricated by an independent oil passage, the configuration of the oil passage is significantly simplified, and processing is facilitated and costs are reduced. In addition, the first and second
The oil jet nozzle can be provided so as to inject lubricating oil toward a position near each winding part of the first and second drive sprockets in the first and second chains, so both chains can be efficiently lubricated. Further, the oil hole or the built-up portion for providing the hole acts as a rib of the chain case, and the rigidity of the case is improved.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and FIG. 1 is a front view showing the end face where the camshaft drive chain of a V-type engine is installed, and FIGS. FIG. 4 is an enlarged front view showing the main parts of FIG. 1; FIG. 3.... Crankshaft, 4 ₁ , 4 ₂ ... Bank, 5 ₁ , 5 ₂ ... Camshaft, 6 ₁ , 6 ₂ ... First and second drive sprockets, 8 ₁ , 8 ₂ ... Chain, 10... ... Chain case, 10a ... Overlay part, 20 ... Oil hole, 23 ₁ , 23 ₂ ... Oil jet nozzle.

Claims (1)

[Scope of utility model registration request] A camshaft is installed in each of two banks arranged in a V shape with the crankshaft at the center.
The camshafts are configured to be driven by the crankshaft through first and second drive sprockets fixed to the crankshaft and first and second chains respectively wound around these sprockets. In the engine, a built-up part extending horizontally is formed in the vicinity of the crankshaft of the chain case that houses the chain, and one oil hole communicating with the lubrication system of the engine is bored in this built-up part. At the same time, first and second oil holes are injected into the oil holes toward predetermined positions of the first and second chains, respectively.
A chain lubricating device for an engine, characterized in that oil jet nozzles are provided at intervals in the horizontal direction.