JPS639778Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to a mechanism in which lubricating oil is supplied from the lubricating oil main pipe in the bed plate to the crank journal bearing part of the type in which a metal cap is bolted onto the metal receiving part of the bed plate. The purpose is to eliminate the need to drill holes in the lower main metal, which has a high surface pressure, and to eliminate the need for piping.

Conventionally, a crankshaft 7 is supported by a lower main metal 3 provided on a metal receiving portion 2 of a base plate 1 and an upper main metal 6 of a metal cap 5 which is fastened onto the base plate 1 by a metal cap bolt 4. When lubricating oil is supplied to the bearing part A, a cut hole 10 is provided that reaches from the main lubricant pipe 8 in the base plate 1 to the oil fill hole 9 in the lower main metal 3, or a journal bearing part is provided vertically upward from the main lubricant pipe 8. A drilled hole that reaches the main metal lubrication hole of A (both not shown)
has been established. However, when lubricating from the lower main metal 3, it is necessary to provide a lubricating hole 9 etc. in the lower main metal 3 that communicates with the cut hole 10.
The pressure-receiving area of the lower main metal 3 is reduced, and the increased surface pressure causes locally high oil film pressure, which may cause the oil film to run out. As a countermeasure to this problem, a method of lubricating the metal cap 5 side using piping is also adopted, and from a functional standpoint, the best and most effective journal lubrication can be expected, but because of the piping structure, reliability against damage to the pipe and joints is low. It becomes a problem.
In addition, it takes time and effort to remove the piping when removing the metal cap, making maintenance difficult.

The present invention forms an oil passage with an annular cross section in the intermediate section between the metal cap bolt and the bolt hole, and connects this oil passage through the drilled hole to the main lubricating oil pipe in the base plate, and the drilled hole in the metal cap. This is intended to solve the above-mentioned conventional problems by communicating with the inner surface of the upper main metal, which will be explained next with reference to the drawings.

The metal cap bolt 4 shown in FIG. A cap nut 14 is screwed onto the protruding portion. The mating surface part 15 (serration part) between the base plate 1 and the metal cap 5
The inner surfaces of the upper and lower bolt holes 13 and 12 are machined to fit a lubricating oil communication pipe 16 in a certain section _L1 . An oil passage 1 with an annular cross section is provided in the intermediate section L ₂ between the upper and lower bolt holes 13 and 12 and the bolt 4.
7 is formed, and the lower half of the oil passage 17 is connected to the base plate 1.
It communicates with the lubricating oil main pipe 8 through a bored hole 19 inside, and the upper end of the oil passage 17 communicates with an oil fill hole 21 in the upper main metal 6 through a bored hole 20. 22 is a blind plug, and 23 is an O-ring that seals the upper end of the oil passage 17. The communication pipe 16 serves to maintain airtightness at the mating surface portion 15 of the oil passage 17.

During operation of the engine, the pressurized lubricating oil in the lubricating oil main pipe 8 passes through the perforation 19 in the base plate 1 and flows into the oil passage 17 with an annular cross section.
, and is supplied to the inner surface of the upper main metal 6 from the oil passage 17 through the perforation 20. When removing the metal cap 5, it is sufficient to remove the cap nut 14, and there is no need to remove other piping.

As explained above, in the present invention, the base plate 1
Place the metal cap 5 on the metal receiving part 2 of the bolt 4.
An oil passage 17 with an annular cross section is formed in the intermediate section L ₂ between the bolt 4 and the bolt holes 13 and 12, and this oil passage 17 is drilled and passes through the hole 19 to the lubricating oil main pipe in the base plate 1. 8, since it communicates with the inner surface of the upper main metal 6 through the cut hole 20 in the metal cap 5, lubricating oil is supplied to the journal bearing part A from the metal cap 5 side. There is no need to drill holes in the lower metal where the oil film pressure is high, and a good oil film pressure distribution can be obtained, and the oil filling resistance is also reduced, improving lubrication performance. Bolt holes 13 and 12 of metal cap bolt 4 and drill hole 1
9 and 20, and does not require any piping, it is more reliable and easier to maintain than the piping-based method of lubricating the metal cap side.

When embodying the present invention, if the mating surface 15 between the base plate 1 and the metal cap 5 has good airtightness, the connecting pipe 16 may be omitted. Further, if the airtightness between the large diameter portion 4a of the bolt 4 and the bolt hole 13 is good, the O-ring 23 can be omitted.

[Brief explanation of the drawing]

FIG. 1 is a partial vertical sectional view perpendicular to the crankshaft of a diesel engine to which the present invention is applied. 1... Base plate, 2... Metal receiver, 4... Metal cap bolt, 5... Metal cap, 6...
...Upper main metal, 8...Lubricating oil main pipe, 12,
13... Bolt hole, 17... Oil path, 19, 20...
...Kirihole.

Claims (1)

[Scope of utility model registration request] A metal cap is bolted onto the metal receiving part of the base plate, and an oil passage with an annular cross section is formed in the intermediate section between the bolt and the bolt hole, and this oil passage is drilled and passes through the hole to lubricate the inside of the base plate. A crank journal bearing oil lubrication mechanism characterized by communicating with the oil main pipe and the inner surface of the upper main metal through a cut hole in the metal cap.