JPS6056242B2 - Crankshaft lubrication system for multi-cylinder engines - Google Patents

Abstract

PURPOSE:To supply lubricating oil evenly from oiling opening to each crankpin, by providing oiling opening at low end of crankshaft and to construct main oil passage to connect oiling opening asympetrically within crankshaft. CONSTITUTION:Crankshaft A is equipped with crank pins of the number corresponds to the number of cylinders and connected to outer surface of each pin 3, 4 via a'-d' are crank arm a-d. Formed on axial line of crank pin 3, 4 are each mail oil passage 7, 8 from which, normal to each bearing a'-d', oiling openings 12, 12' and 13, 13' are formed. Passage 9, 10 to make connection between main oil passage 7, 8 are made with slant against axis of shaft, and passage 9 of outer side connects to oiling opening 5 which is provided at end of shaft. Thus, centrifugal force produced by shaft A supplies oil from oiling opening 5 to each oil passage evenly.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a crankshaft lubrication device for a multi-cylinder engine, which has an oil filler port provided at the end of the crankshaft for lubricating the outer periphery of the crank pin.

Conventionally, this type of lubrication device has a structure in which a plurality of crank pins are provided with main oil supply passages, an oil supply port is opened on the outer periphery of the pin, and the main oil supply passage is communicated with the oil supply port. Lubricating oil is pumped through the oil filler port at the end of the crankshaft, passes through the main oil supply path, and is supplied to the outer periphery of each crank pin from the oil filler port.

However, in the above-mentioned conventional type, each main oil supply passage and oil supply port provided on a plurality of crank pins are set to have the same eccentricity from the center of rotation of the crankshaft, and furthermore, the farther a crankpin is from the oil supply port, the greater the injection pressure due to passage resistance. Therefore, among the cylinders, the closer the oil filler port is to the cylinder, the more lubricant oil is supplied, and the farther the cylinder is from the oil filler port, the smaller the amount of lubricant oil supplied. However, in view of the above-mentioned conventional circumstances, the present invention aims to improve the lubrication function by making the amount of oil supplied to the crank pin portion of each cylinder approximately the same.
The device of the present invention utilizes the centrifugal force acting on the lubricating oil in the oil passage to change the magnitude of the oil pressure in the main oil supply passage of the crank pin, and constitutes a means for making the discharge pressure of each oil supply port approximately uniform. It is characterized by

To enumerate a few examples of the above means, the eccentricity of each main oil supply path with respect to the rotation center of the crankshaft is gradually increased as the distance from the oil filler port increases, and the eccentricity of the opening end of the oil filler port with respect to the crankshaft rotation center is There is a configuration in which the main oil supply path is set larger as the distance from the main oil supply path increases, or a configuration in which the former two are combined.

With the above configuration, as the crankshaft rotates, the centrifugal force applied to the main oil supply path and/or the oil filler port gradually increases as the distance from the oil filler port increases, and the magnitude of the injection pressure in each main oil feed path is corrected. Uniform discharge pressure acts.

Embodiments of the present invention will be described with reference to the drawings.
In Fig. 5, A, A'', A'' are the crankshafts of a four-cylinder engine, A, b, c, d are connecting rods, B is a crankcase, and each crankshaft A, A'', A'''' is equipped with two crank pins 3 and 4 arranged symmetrically from the rotation center line 0 via two pairs of crank webs 1, 1'', 2, 2'', and has a lubrication system that pumps lubricating oil to the shaft end. It has the same basic shape with a mouth 5.

Each of the crankshafts A, A'', A'''' connects the bearing portions Y, b'' of the connecting rods A, b to the crank pin 3, and the bearing portions C'', C'' of the connecting rods C, d to the crank pin 4, Connect d''.

1 and 2 show a first embodiment in which the eccentricity of the main oil supply passage acting as an oil reservoir received by each crank pin 3, 4 is different. To explain this, the crankshaft A is connected to each crank Holes are formed in the pins 3 and 4 in the axial direction from the sides of the crank webs 1 and 2'', respectively, and plugs 6 made of steel balls are provided at the open ends of the holes.
, 6'' are provided, and main oil supply passages 7 and 8 are formed by sealing them.
One of the main oil supply passages 7 communicates with the oil supply port 5 at the end of the shaft through a passage 9 which is bored across the crank web 1 and the crankshaft A.

Further, the crankshaft A passes through the main oil supply passage 7 from the side surface of the crank web 1, and has a passage 10 bored toward the inner end of the other main oil supply passage 8.
, 8 are communicated.

A plug 11 made of a steel ball is sealed at the open end of the passage 10.

The main oil supply passages 7 and 8 are formed at positions with different eccentricities 11 and 12 with respect to the rotation center line O of the crankshaft A, so that the eccentricity 12 of the main oil supply passage 8 which is far from the oil filler port 5 is set to the eccentric amount 12 which is closer to the oil filler port. It is set larger than the eccentricity 11 of the main oil supply path 7 on the side.

Oil fill ports 12, 12'' are bored in the crank pin 3 in the radial direction, and the oil fill ports 12, 12'' are communicated with the main oil feed path 7.

Further, the crank pin 4 has oil fill ports 13, 13 in the radial direction.
'' are opened and communicated with the main oil supply path 8, respectively.

The above oil filler ports 12, 12'', 13, 13'' are connected to the large end bearings a'', b'', c'', d'' of the connecting rods A, b, c, d, respectively.
The opening faces the inner surface, and each opening end is set to have the same amount of eccentricity with respect to the rotation center line 0. The lubricating oil pumped from the oil filler port 5 at the end of the crankshaft A is then transferred to the main oil supply path 7,
8 and passages 9, 10, oil filler ports 12, 12″, 13, 13
'', and as the crankshaft A rotates, the centrifugal force causes oil to be discharged from the oil filler ports 12, 12'', 13, 13'' to the outer periphery of the crank pins 3, 4 to form bearing parts a'', b'', c''. ,d
Lubricate ″.

Since the eccentricity 12 of the main oil supply passage 8, where the injection pressure is lower than that of the main oil supply passage 7 due to passage resistance, etc., is set larger than the eccentricity 11 of the other main oil supply passage 7, the lubricating oil in the main oil supply passage 8 is The action of the centrifugal force applied to the main oil supply path 7 is greater than that of the other main oil supply path 7,
Therefore, the magnitude of the injection pressure in both the main oil supply passages 7, 8 is corrected, and the discharge pressure applied to the opening ends of each oil supply port 12, 12'', 13, 13'' becomes approximately uniform, and the pressure on both the crank pins 3, 4 is approximately equal. The same amount of lubricating oil is supplied.

3 and 4 show a second embodiment in which the eccentricity of the oil supply opening end of each crank pin 3, 4 is different. To explain this, the crankshaft A'' is made to correspond to the first embodiment. and 7'' are the main oil supply passages provided on the crank pin 3, 8'' are the main oil supply passages provided on the crank pin 4, 9'' and 1'' are passages, 14,
1C and 15,15'' are oil fill ports.

The main oil supply passages 7'' and 8'' are formed at the center of the crank pins 3 and 4, respectively, and are positioned with the same eccentricity 1 relative to the rotational center line 0 of the crankshaft A.

The opening end 16 of the oil filler port 14, 14'' is connected to the crank pin 3.
Position it closer to the rotation center line 0 than the center, and connect the oil filler port 15,1
5'' is located outward from the center of the crank pin 4, thereby reducing the eccentricity of the opening end 17 of the oil filler port 15, 15'' with respect to the rotation center line 0! The opening end 16 of the fuel filler port 14, 1C
The eccentricity L1 is set to be larger than the eccentricity L1. In the second embodiment, since the eccentricity L2 of the oil filler opening end 17 on the side farther from the oil filler hole 5 is made larger than that of the oil filler opening end 16 on the side closer to the oil filler hole 5, the opening end 17 The centrifugal force exerted on the opening end 16 is larger than that on the opening end 16, so that the magnitude of the injection pressure at both ends is corrected, and the discharge pressure becomes approximately uniform.

Next, FIGS. 5 and 6 show a third embodiment in which the eccentricity of the main oil supply passage and the opening end of the oil supply port are different, and the crankshaft A''
7'' and 8'' are the main oil supply passages 92 and 10'', 18, 18'' and 19 and 19'' are the oil fill ports, 20 is the open end of the oil fill ports 18 and 1'', and 21 is the oil fill port 19. , 19'' open end.

The main oil supply passages 7″, 8″ are the oil filler ports 5 as in the first embodiment.
The eccentricity 12 of the main oil supply passage 8'' which is further away is provided at a position set to be larger than the eccentricity 11 of the main oil supply passage 7'' which is closer to the oil filler port 5. The opening ends 20 and 21 are connected to the oil filler port 5 as in the second embodiment.
Eccentricity L of the opening end 21 of the oil filler port 19, 19″ which is further away
2 is set to be larger than the eccentricity of the opening end 20 of the other oil filler port 18, 1'.

In this third embodiment, the eccentricity of the main oil supply passages 7'' and 8'' is 1, 1.
2 and the difference in eccentricity Ll, L2 of the open ends 20, 21 to correct the magnitude of the injection pressure of each crank pin part, and the crank pin is far away from the oil filler port 5. It is particularly effective when applied.

Although the above example shows a type 4-cylinder crankshaft,
The present invention is applicable regardless of whether the engine type is a parallel type or a horizontally opposed type. As described above, the present invention is formed on each crank pin of a multi-cylinder engine, and is designed to correct the magnitude of oil pressure in each main oil supply passage through which lubricating oil is pumped from the oil filler port at the end of the crankshaft. By increasing the eccentricity of the main oil supply path or the opening end of the oil filler port with respect to the center of rotation, the centrifugal force that acts on the lubricating oil is used, such as increasing the eccentricity of the main oil supply path or the opening end of the oil filler port as the distance from the oil filler port increases. Since the means for making the lubricating oil substantially uniform is provided, substantially the same amount of lubricating oil is supplied to each crank pin portion, and accordingly, each cylinder is supplied with just the right amount of lubricating oil, thereby improving the lubrication function.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional side view of the first embodiment of the present invention, Fig. 2 is a sectional view taken along the line ■-■, Fig. 3 is a longitudinal sectional side view of the second embodiment, and Fig. 4 is the oil filler port of each crank pin. FIG. 5 is a longitudinal cross-sectional side view of the third embodiment, and FIG. 6 is a cross-sectional explanatory view showing the eccentric positions of the main oil supply passage and oil filler port of each crank pin.

Claims (1)

[Scope of Claims] 1. In a crankshaft of a multi-cylinder engine having a plurality of crank pins in the axial direction, an oil fill port is provided at the end of the shaft, and a main oil feed path is provided for each crank pin, which opens to the outer periphery of the pin. In addition to providing an oil supply port, the main oil supply passages are sequentially connected and communicated with the oil supply port, and the lubricating oil passages for each crank pin are configured asymmetrically to reduce the effects of centrifugal force acting on the internal lubricating oil unequally. A crankshaft lubricating device comprising means for substantially equalizing the discharge pressure of each oil filler port. 2. In claim 1, a main oil supply passage is formed in each crank pin parallel to the crank pin axis, and a relatively small diameter oil supply port is communicated with the main oil supply passage, and
A crankshaft lubricating device in which a main oil supply passage bored in the crank pin on the side closer to the oil filler port is provided closer to the crankshaft center than the other main oil supply passage. 3. The crankshaft lubricating device according to claim 2, wherein the oil supply port is bored outward from the main oil supply passage. 4. In claim 1 or 2, the oil filler port drilled in the crank pin on the side closer to the oil filler port is
A crankshaft lubricating device that opens at a position closer to the axis of the crankshaft than the oil supply port drilled in the other crank pin. 5. In claim 1, 2, 3, or 4, the engine is a V-type four-cylinder engine, and the connecting rods of the cylinders forming a V-type arrangement are connected to a common crank pin. The crankshaft lubrication device has an oil filler port for each connecting rod. 6. In claim 1, 2, 3, or 4, the engine is a horizontally opposed four-cylinder engine, and the connecting rods of the cylinders arranged opposite to each other are connected to a common crank pin. , a crankshaft lubrication device with an oil filler port for each connecting rod. 7. In claim 1 or 2 or 3 or 4, a crank pin is provided for each connecting rod of cylinders arranged in parallel with each other, and one crank pin is connected to one connecting rod. A crankshaft lubricating device that lubricates the