JPH0468485B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to internal combustion engines, and more specifically,
This invention relates to a structure for coupling a piston pin to a small end of a connecting rod.

Background Art The prior art is shown in FIG. piston 7
1 is connected to a connecting rod 1 via a piston pin 2. The connecting rod 1 has a small end fastened to a piston pin 2 by a bolt 3, a trunk 4 following the small end, a large end 6 fixed to the trunk 4 by a bolt 5, and a large end 6. It consists of a large end cap 7 which is secured by bolts 8 to the cap. The dividing planes of these connecting rods are indicated by reference numerals 72, 73, 74. During maintenance of the piston 71 and piston pin 2, the bolts 5 are removed and the trunk 4 of the connecting rod 1 and the large end cap 7 are removed. The end portion 6 is separated by a dividing surface 73.

In another prior art, as shown in FIG. 5, the trunk 4a and the large end 6a of the connecting rod 1a are separated by a dividing surface 75 that is closer to the large end 6a by means of a bolt 5a than in the prior art shown in FIG. It is configured to be divided.

Problems to be Solved by the Invention The problems with these conventional techniques are that the number of bolts for connection at the dividing plane of the connecting rod is relatively large, and therefore the work of tightening the bolts is also large. It takes time and effort to check the fastening state.

The present invention solves the above-mentioned problems by reducing the number of bolts that fasten the connecting rod, and provides a connecting rod structure that facilitates maintenance of pistons and the like.

Means for Solving the Problems The present invention provides a structure 25 that forms the crank chamber 24.
A cylinder liner 11 extending downward is fixed to the upper part of the cylinder liner 11, a piston 14 is housed in the cylinder liner 11, and a piston pin 16 is inserted through the piston 14.
The upper part 16c of the piston pin 16 is supported by the piston 14 via the first bearing 15 over the entire length of the piston pin 16, and
The lower intermediate portion 36 is supported by the piston 14 via the first bearing 15, and both axial ends 16a, 1 of the piston pin 16 are supported by the piston 14 via the first bearing 15.
6b is formed with notches 32 and 33 that are open downward, and these notches 32 and 33 are connected to the mounting surface 32 parallel to the axis 16d of the piston pin 16.
a, 33a, first screw holes 47 to 50 are formed in the mounting surfaces 32a, 33a, and the outer surface 3 of the intermediate portion 36 of the piston pin 16.
A second screw hole 41 is formed in 6a, and the spacing piece 17 has a pair of upper parts 34 and 35 that abut on the mounting surfaces 32a and 33a, respectively, and between these upper parts 34 and 35, the intermediate part A recess 37 is formed into which the upper part 34,
The piston pin 1 extends from 35 to the lower end surface 17b.
First insertion holes 43 to 46 are formed in the upper part 34 and extend perpendicularly to the axis 16d of the second screw hole 41.
An insertion hole 40 is formed, and the connecting rod main body 18 includes a small end 51, a trunk 52 extending downward from the small end 51, and a trunk 52.
The small end 51 has an upper end surface 51a that comes into contact with the lower end surface 17b of the spacing piece 17, and is further along the axis of the piston pin 16 than the trunk 52. It has attachment parts 51b, 51c which protrude outward from both sides, and each attachment part 51b,
51c, third insertion holes 56 to 59 corresponding to the first insertion holes 43 to 46 are formed, and the first bolt 42 is inserted into the first and third insertion holes 43.
~ 46, 56 ~ 59 are inserted, and one end thereof is the first
The second bolt 39 is screwed into the screw holes 47 to 50, and the other end is screwed into a nut 60 below the attachment parts 51b and 51c of the small end 51. The large end 53 and the large end cap 55 sandwich the crank pin 20 via the second bearing 19, and the third
The upper end surface 51a of the small end 51 is connected to the crank pin 2 by a bolt 54.
0, it is located below the lower end 14a of the piston 14 and the lower end 11a of the cylinder liner 11, and the crank chamber 24 of the frame 25 is large enough to allow the connecting rod main body 18 to take a lying position. A pair of maintenance windows 26 and 27 are formed on opposite sides of the frame 25 at positions where the third bolt 54 and the small end 51 face each other when the frame 25 is in the above-mentioned position. Each maintenance window 26, 27 has a lid 28,
This internal combustion engine is characterized in that 29 are provided so as to be openable and closable.

Embodiment FIGS. 1 and 2 show cross-sections of one embodiment of the invention. The top of the cylinder liner 11 of an internal combustion engine with a crank piston is closed off by a cylinder head 12 . The cylinder liner 11 is surrounded by a cylinder jacket 13. Inside the cylinder liner 11 is a piston 1.
4 is stored. A piston pin 16 is supported by the piston 14 via a bearing 15. There is a spacing piece 17 at the bottom of the piston pin 16, and a connecting rod body 18 is bolted to the bottom of the spacing piece 17. The connecting rod body 18 is connected to the crank pin 2 via a bearing 19 at its large end.
Connected to 0. The crank pin 20 is fixed to a crank arm 21, and the crank arm 21 is fixed to a crankshaft 22. On the opposite side of the crank arm 21 is a counterweight 2.
3 is formed. The crank chamber 24 is connected to the frame 2
It is divided by 5. Windows 26 and 27 for maintenance are provided on the sides of this frame 25, and the windows 26 and 27 are closed by lids 28 and 29 so as to be openable and closable. The frame 25 is fixed in a fixed position by a bed plate 30, for example to the bottom of the ship when used in a ship. The lower part of the crank chamber 24 is an oil pan 31.

FIG. 3 shows an exploded structure of an embodiment of the invention. At both ends 16a and 16b of the piston pin 16 in the axial direction, there are notches 3 that are open downward.
2 and 33 are formed. This notch 32,3
3, a pair of upper parts 34 and 35 of the spacer piece 17 are brought into contact with each other. A recess 37 into which the intermediate portion 36 of the piston pin 16 fits is formed between the upper portions 34 and 35 of the spacing pieces. Inner surfaces 34a, 35a of the spacing piece upper portions 34, 35 facing the recess 37 face outer surfaces 36a, 36b of the intermediate portion 36 of the piston pin, respectively. The fixing bolt 39 is inserted through an insertion hole 40 formed in the upper part 34 of one of the spacing pieces, and is inserted into a threaded hole 4 formed in the outer surface 36a of the intermediate portion 36 of the piston pin.
1 is screwed on. With this, piston pin 1
Even if a bolt 42 (described later) that fastens the piston pin 6 and the spacing piece 17 is removed, the spacing piece 17 is prevented from falling off the piston pin 16. The spacer piece 17 has insertion holes 43, 44 for fastening bolts extending vertically perpendicular to the axis of the piston pin 16;
5 and 46 are formed, respectively. This insertion hole 4
Piston pin 1 corresponding to 3, 44; 45, 46
6 Attachment surfaces 32a of notches 32 and 33 at both ends,
Screw holes 47, 48; 49, 50 are formed in 33a, respectively.

The connecting rod main body 18 includes a flange-shaped connecting rod small end 51, a trunk 52 extending downward from the connecting rod small end 51, and a connecting rod large end 53 connected to the trunk 52.
and a large end cap 55 secured to the connecting rod large end 53 by a bolt 54. The connecting rod large end 53 and large end cap 55 are connected to the crank pin 20 via the bearing 19 as described above.

The connecting rod small end 51 has the insertion hole 4 of the spacer piece 17.
Through-holes 56, 57; 58, 59 are formed to correspond individually to 3, 44; 45, 46. The upper end surface 51a of this connecting rod small end portion 51 is connected to the spacing piece 17.
comes into contact with the lower end surface 17b of. The threaded portion 42a of the bolt 42, which is commonly inserted through the insertion holes 43 and 56, is screwed into a threaded hole 47 formed downward in the mounting surface 32a of the piston pin 16. A nut 60 is screwed onto the other threaded portion 42b of the bolt 42 from below the small end portion 51 of the connecting rod. In this way, the bolt 42 connects the spacer piece 17 to the piston pin 16.
The small end 51 of the connecting rod is secured via the connecting rod. The same applies to the remaining insertion holes 44, 45, 46 and the corresponding insertion holes 57, 58, 59.

The upper end surface 51a of the connecting rod small end 51 fixed to the spacing piece 17 is connected to the connecting rod small end 51 when the crank pin 20 is at the lowest position as shown in FIGS. 17 and crankshaft 2
When the connecting rod main body 18 is rotated integrally with the cylinder liner 2, the vicinity of the upper end surface 51a of the connecting rod small end 51 is set so as not to come into contact with the lower end 11a of the cylinder liner 11. The axis of crankshaft 22 is indicated by reference numeral 62 in FIG.

The cylinder liner 11 extends vertically and is fixed to the upper part of a frame 25 that forms the crank chamber 24 . The piston pin 16 passes through the piston 14. The upper part 16c of the piston pin 16 is the total length of the piston pin 16 (the total length in the left and right direction in FIG. 2).
is supported by the piston 14 via a bearing 15. Further, a lower intermediate portion 36 of the piston pin 16 is supported by the piston 14 via a bearing 15. The notches 32 and 33 formed in the piston pin 16 open downward at both axial ends 16a and 16b of the piston pin 16. These notches 32 and 33 are located along the axis 1 of the piston pin 16.
It has mounting surfaces 32a and 33a parallel to 6d.
Insertion holes 43 to 46 formed in the spacing piece 17
is from the upper parts 34 and 35 of the spacer piece 17 to the lower end surface 17
b, extending perpendicularly to the axis 16d of the piston pin 16.

The small end 51 of the connecting rod main body 18 has attachment parts 51b and 51c that protrude outward from both the axial direction of the piston pin 16 than the trunk 52, and each of the attachment parts 51
Insertion holes 56 to 59 are formed in b and 51c.

As is clear from FIGS. 1 and 2, the upper end surface 51a of the small end 51 is located at the lowest position of the crank pin 20 and below the lower end 14a of the piston 14 and the lower end 11a of the cylinder liner 11. be.

The crank chamber 24 of the frame 25 is connected to the connecting rod main body 18
has a size that allows a lying position, as shown by the imaginary line 64 in FIG. window 26,
27 is the bolt 54 when in the above posture.
and the frame 25 at the position where the small end 51 faces, respectively.
are formed on both opposing sides of the

The screw holes 47 to 50 are attached to the mounting surfaces 32a and 33a.
is formed perpendicular to. This facilitates manufacturing and also allows the axis 16 of the piston pin 16 to
It becomes possible to apply a load perpendicular to d to the piston pin 16, and smooth movement of the piston 14 becomes possible.

During maintenance, move the crank pin 20 to the
Set the lid to the lowest position as shown in the figure and Figure 2, then
8 and open the window 26. Therefore, the connecting rod body 1
The nuts 60 and bolts 42 corresponding to the insertion holes 56 of the small end portions 51 of the connecting rods 8 are removed, and the nuts and bolts associated with the remaining insertion holes 57, 58, 59 are similarly removed. At this time, the spacing piece 17 is fixed to the piston pin 16 by the fixing bolt 39.
It will remain connected to the base and will not fall.

Next, by fixing the trunk 52 of the connecting rod main body 18 to the counterweight 23 using a roughly U-shaped fixing fitting 63 as shown in FIG. 2, the crankshaft 22 can be rotated. Thus, the state indicated by reference numeral 64 in FIG. 1 can be achieved.

Effects As described above, according to the present invention, the connecting rod main body 18
Since the small end 51 of the piston pin 16 is fastened to the piston pin 16 by the common bolt 42 with the spacing piece 17 interposed, the number of bolts 42 and 54 can be reduced, and the number of bolts used during maintenance can be reduced. The work of releasing and tightening 42 and 54 becomes easier,
Furthermore, the fastening state of the bolts 42 and 54 can be easily confirmed. That is, in the present invention, since the connecting rod main body 18 can be assembled and disassembled using the first bolt 42 and the third bolt 54, it is possible to manage the tightening of these first and third bolts 42 and 54. It is possible to reduce the amount of work and prevent accidents caused by poor tightening, and it is also possible to shorten and simplify the inspection work for assembling and disassembling the connecting rod body 18.

In the present invention, the piston pin 16 and the spacing piece 17 are fixed by the second bolt 39, so that even after the first bolt 42 is removed, the piston pin 16 and the spacing piece 17 are integrated. The dividing surface on the small end portion 51 side is formed at the lower end surface 17b of the spacing piece 17 and the upper end surface 51a of the small end portion 51.
At the lowest position, that is, the bottom dead center, below the lower end 14a of the piston 14 and the lower end 11a of the cylinder liner 11, and the small end 51 is tightened as follows.
The spacer piece 17 with the piston pin 16 and the small end 51 have a so-called three-piece tightening structure, and the first bolt 42 is
The third bolt 54 is used at the large end 53 to achieve the above-mentioned effect.

Furthermore, in the present invention, as described above, the small end portion 51
The upper end surface 51a is at the lowest position of the crank pin 20 and is below the lower end 14a of the piston 14 and the lower end 11a of the cylinder liner 11.
8 has a size that allows it to be in a lying position,
In this position, a pair of maintenance windows 26 and 27 are formed on both opposing sides of the frame 25 at positions facing the third bolt 54 and the small end 51, respectively, so the lids 28 and 29 are opened. Open it and remove the third bolt 54 and the trunk 5 inside the crank chamber 24.
An excellent effect is achieved in that the work of tightening and removing the third bolt 54 from the second bolt 54 can be easily performed. This is particularly important in view of the large weight of the connecting rod body 18 in large diesel engines and the like, from the viewpoint of facilitating maintenance.

Further, according to the present invention, the mounting surfaces 32a, 33a of the notches 32, 33 of the piston pin 16 and the upper portions 34, 35 of the spacing piece 17 that are fixed to the mounting surfaces 32a, 33a, respectively, are attached to the piston 14. Therefore, during maintenance, after installing the stop bolt 39 and removing the nut 60 and bolt 42, the crankshaft 22 is rotated, and then the stop bolt 39 is removed and the spacer piece 17 is attached to the piston pin. You can leave from 16. As a result, in a relatively large internal combustion engine as in the present invention, each component is disassembled and each component 14, 17 having a small weight is removed from the frame 2.
5 and the piston 14, which is integral with the piston pin 16, can be easily taken out.

Furthermore, since the spacing piece 17 can be removed from the piston pin 16 in this way, the piston 1
4 from the cylinder liner 11 into the frame 25, the swinging component 1 is attached to the piston 14.
7 is not attached, therefore, the disassembly and assembly work when taking out and inserting the piston 14 into the frame 25 and outside the frame 25 is extremely easy, and the safety of the work is ensured. The excellent effect of being able to do this is achieved. This is particularly important since the invention is particularly well suited for implementation in large internal combustion engines.

[Brief explanation of drawings]

FIG. 1 is a sectional view of an internal combustion engine according to an embodiment of the present invention, FIG. 2 is a sectional view showing the crank pin 20 in the lowest position, and FIG. 3 shows the piston pin 16 and related components. FIG. 4 is an exploded perspective view, FIG. 4 is a front view showing the structure of the prior art, and FIG. 5 is a front view showing the structure of another prior art. 16...Piston pin, 17...Spacer piece, 18
...Connecting rod body, 42, 54...Bolt, 52...
... Executive, 53 ... Connecting rod big end, 55 ... Big end cap.

Claims (1)

[Claims] 1. The lower end of a vertically extending cylinder liner 11 is fixed to the upper part of a frame 25 that forms a crank chamber 24, a piston 14 is housed in the cylinder liner 11, and a piston pin 16 is connected to the piston. Insert 14,
The upper part 16c of the piston pin 16 is supported by the piston 14 via the first bearing 15 over the entire length of the piston pin 16, and
The lower intermediate portion 36 is supported by the piston 14 via the first bearing 15, and both axial ends 16a, 1 of the piston pin 16 are supported by the piston 14 via the first bearing 15.
6b is formed with notches 32 and 33 that are open downward, and these notches 32 and 33 are connected to the mounting surface 32 parallel to the axis 16d of the piston pin 16.
a, 33a, and the mounting surfaces 32a, 33a have first screw holes 47 to 50 perpendicular to the mounting surfaces 32a, 33a.
is formed, and the outer surface 3 of the intermediate portion 36 of the piston pin 16
A second screw hole 41 is formed in 6a, and the spacing piece 17 has a pair of upper parts 34 and 35 that abut on the mounting surfaces 32a and 33a, respectively, and between these upper parts 34 and 35, the intermediate part A recess 37 is formed into which the upper part 34,
The piston pin 1 extends from 35 to the lower end surface 17b.
First insertion holes 43 to 46 are formed in the upper part 34 and extend perpendicularly to the axis 16d of the second screw hole 41.
An insertion hole 40 is formed, and the connecting rod main body 18 includes a small end 51, a trunk 52 extending downward from the small end 51, and a trunk 52.
The small end 51 has an upper end surface 51a that abuts the lower end surface 17b of the spacing piece 17, and a large end cap 55 to be fixed to the large end 53. 52, the mounting portions 51b, 51c protrude outward in the axial direction of the piston pin 16, and each mounting portion 51b,
51c, third insertion holes 56 to 59 corresponding to the first insertion holes 43 to 46 are formed, and the first bolt 42 is inserted into the first and third insertion holes 43.
~46, 56~59 are inserted, and one end thereof is the first
The second bolt 39 is screwed into the screw holes 47 to 50, and the other end is screwed into a nut 60 below the attachment parts 51b and 51c of the small end 51. The large end 53 and the large end cap 55 sandwich the crank pin 20 via the second bearing 19, and the third
The upper end surface 51a of the small end 51 is connected to the crank pin 2 by a bolt 54.
0, it is located below the lower end 14a of the piston 14 and the lower end 11a of the cylinder liner 11, and the crank chamber 24 of the frame 25 is large enough to allow the connecting rod main body 18 to take a lying position. A pair of maintenance windows 26 and 27 are formed on opposite sides of the frame 25 at positions where the third bolt 54 and the small end 51 face each other when the frame 25 is in the above-mentioned position. Each maintenance window 26, 27 has a lid 28,
An internal combustion engine characterized in that 29 are provided so as to be openable and closable.