JPH01280666A - Cylinder block structure - Google Patents

Abstract

PURPOSE:To enable simple formation of a blowby gas passage and to reduce the size thereof, by a method wherein mounting tools are mounted in respective mounting hole parts formed in the upper and lower parts of a cylinder block, and a communication passage is formed in each mounting tool. CONSTITUTION:A first mounting bolt 16 is engaged with a screw part 14 at the tip of a first mounting hole part 10 formed in the upper part of a cylinder block 2 to mount a cylinder head 4. A second mounting bolt 18 is engaged with a screw part 14 at the tip of a second mounting hole 12 formed in the lower part of the cylinder block 2 to mount a crank bearing part 28. A communication passage 26 is formed with through-holes 20 and 22 of the mounting bolts 16 and 18, respectively, and a space part 24 in the screw part 14. The cylinder head 4 is communicated to an oil pan 6 through the communication passage 26, which is used as a blowby gas passage or an oil drop passage.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a cylinder block structure, and in particular, to a cylinder block structure in which a cylinder head is mounted on the upper part of the cylinder block.
This invention relates to a cylinder block structure that forms an internal combustion engine by installing an oil pan at the bottom.

[Conventional technology]

An internal combustion engine is made up of a cylinder head, a cylinder block, and an oil pan.The cylinder head is equipped with parts such as intake valves, exhaust valves, and spark plugs for each cylinder, as well as a valve train that operates the intake and exhaust valves. A mechanism is provided.

Further, a cylinder is formed inside the cylinder block, and a piston reciprocates in the vertical direction within this cylinder, and the reciprocating movement of the cylinder is converted into rotational movement via a connecting rod and a crankshaft.

Some cylinder blocks are disclosed in Japanese Utility Model Publication No. 57-45387. The engine assembly structure disclosed in this publication involves installing stud bolts in the crankcase, inserting the bolts from above the cylinder head, and threading them onto the stand bolts to integrally connect the cylinder head, cylinder block, and crankcase. The engine is assembled and connected to improve the ease of assembly of the engine.

There is also one disclosed in Japanese Utility Model Application Publication No. 57-68140. The main body structure of the internal combustion engine disclosed in this publication is as follows:
A female threaded insert is provided in the cylinder block, and a hem bolt for fixing the cylinder head and a gap bolt for fixing the link cassop to the main are screwed onto both ends of this female threaded insert, respectively, and the cylinder head and main hair ring cap are fixed to the cylinder block. This reduces the number of machining steps for fixing holes and improves machining workability.

[Problem that the invention seeks to solve]

By the way, in the conventional cylinder block structure, as shown in FIG. 12, a first mounting hole 110 for receiving a cylinder head is formed in the upper part of the cylinder block 102, and an oil pan is mounted in the lower part of the cylinder block 102. A second mounting hole 112 was formed, and the first and second mounting holes 110, ]12 were provided without communicating with each other.

For this reason, when drilling the first and second mounting holes 110 and 112, each drilling operation is required, which is economically disadvantageous due to poor processing efficiency and high cost. However, there is a problem that the mounting bolts may loosen and fall off.

In addition, in the engine assembly structure disclosed in Japanese Utility Model Publication No. 57-45387, drilling of the mounting holes is relatively easy, but the structure of the stud holes is complicated and manufacturing is difficult. In addition to increasing the cost, there is a risk that the screwed part may loosen due to vibrations when the engine is running and fall off.Furthermore, there is no mounting hole configured to provide a blow-high gas passage or other functions. This has the disadvantage that it is necessary to create a passage, which complicates the configuration and is disadvantageous in practice.

Furthermore, the body structure of the internal combustion engine disclosed in Japanese Utility Model Application Publication No. 57-68140 requires a female thread insert, which increases the number of parts, increases cost, and causes vibrations when the internal combustion engine is driven. There is a risk that the threaded part of the female screw insert may loosen and fall off, and there is no mounting hole configured to have a blow-high gas passage or other functions, so a separate passage must be created, making the configuration complicated. This has the disadvantage of being disadvantageous in practice.

[Purpose of the invention]

SUMMARY OF THE INVENTION In order to eliminate the above-mentioned disadvantages, an object of the present invention is to provide a first mounting hole in the upper part of the cylinder block and a second mounting hole in the lower part of the cylinder block so as to communicate with each other, and to engage with the first mounting hole. By providing a first fixture and a second fixture that engages with the second mounting hole, and providing a communication passage in the first and second fixtures to communicate between the upper and lower parts of the cylinder block. The purpose is to realize a practically advantageous cylinder block structure by making the communication passage function as a blow-high gas passage or an oil drop passage.

[Failure to solve the problem]

In order to achieve this object, the present invention provides a cylinder block in which a cylinder head is mounted on the upper part and an oil pan is mounted on the lower part to form an internal combustion engine. and a second mounting hole for mounting the crankshaft in the lower part of the cylinder block, and a first mounting tool that engages with the first mounting hole is provided, and the second
The present invention is characterized in that a second fixture is provided that engages with the mounting hole, and a communication passage is provided in the first and second fixtures to communicate the upper and lower parts of the cylinder block.

[Effect]

With the above-described configuration, when forming an internal combustion engine, the first fitting is engaged with the first mounting hole in the upper part of the cylinder block to mount the cylinder head, and the cylinder head is attached to the second mounting hole in the lower part of the cylinder block. Attach the crankshaft by engaging the second fitting, and provide a communication passage in the first and second fittings to connect the upper and lower parts of the cylinder block, and the communication passage functions as a blow-by gas passage and an oil drop passage. This is a practical advantage.

〔Example〕

Embodiments of the present invention will be described in detail below based on the drawings.

1 to 5 show a first embodiment of the invention.

In FIGS. 1-4Q, 2 is a cylinder block of an internal combustion engine. The internal combustion engine (not shown) is formed by a cylinder head 4, a cylinder block 2, and an oil pan 6, and has a plurality of cylinders, for example, three cylinders 8-1, which burn an air-fuel mixture.
．． 8-2.8-3 is formed.

As shown in FIGS. 1 to 3, the cylinder block 2 has a first mounting hole 10 in the upper part of the cylinder block 2, and a second mounting hole 12 in the crankshaft bearing part 28, which will be described below, in the lower part of the cylinder block 2. Although these first and second mounting holes 10.12 may be connected and have different centers, in this embodiment they are provided so that they have the same center.

A threaded part 14 is provided between the tips of the first and second mounting holes 10.12, for example, at a position below the center height position Lh of the cylinder block 2, and this threaded part 14 allows the first and second mounting holes 10. The second hole also connects hole 10.12. Also,
First and second mounting bolts 16.1B, which are first and second fittings, are screwed into the threaded portion 14, respectively, and the first and second mounting bolts 116.18 are configured so as not to contact each other.

At this time, the inner diameter d of the threaded portion 14 is formed to be smaller than the inner diameter of the first and second mounting holes 10.12.

The first and second mounting bolts 16.18 are provided with first and second through holes 20.22 that penetrate in the axial direction, and when fastened, the first through hole 20, the space 24 in the threaded part 14, and the second Through hole 22
This constitutes a communication passage 26, which communicates the inside of the cylinder head 4 in the upper part of the cylinder block 2 with the inside of the oil pan 6 in the lower part of the cylinder block 2.

Note that reference numeral 28 is a crank bearing portion, and 30 is a crankshaft supported by the cylinder block 2 and the crank bearing portion 28.

Next, the effect will be explained.

When forming an internal combustion engine (not shown), the first mounting bolt 16 is engaged with the threaded part 14 at the tip of the first mounting hole 10 on the upper part of the cylinder block 2 to mount the cylinder head 4, and the cylinder head 4 is mounted on the lower part of the cylinder block 2. The second mounting bolt 18 is engaged with the threaded portion 14 at the tip of the second mounting hole 12 to remove the crankshaft 28, and the oil pan 6 is attached to the lower part of the cylinder block 2.

At this time, a communication passage 26 is formed by the first through hole 20, the space 24 in the threaded portion 14, and the second through hole 22.

This communication passage 26 communicates between the inside of the cylinder head 4 at the upper part of the cylinder block 2 and the inside of the oil pan 6 at the lower part of the cylinder block 2, and a blower gas passage through which the high blow gas inside the cylinder head 4 flows out from inside the oil pan 6. , or the communication passage 2 serves as an oil drop passage for returning the oil in the cylinder head 4 to the oil pan 6.
6 works.

As a result, when an internal combustion engine (not shown) is formed by the cylinder head 4, cylinder block 2, crank bearing 28, and oil pan 6, the first through hole 20 and the threaded portion 1
The communication passage 2 is formed by the space 24 in 4 and the second through hole 22.
6 is formed, and this communication passage 26 can function as a blower gas passage or an oil drop passage, and the blower gas passage or oil drop passage can be made smaller or unnecessary, and the structure is simplified, making it possible to reduce the size of the internal combustion engine. In addition to contributing to the
This is practically advantageous.

Further, when forming the communication passage 26, first the first
, the second mounting holes 10.12 are simultaneously drilled from the top and bottom directions, and then the threaded part 14 is carved between the tips of the first and second mounting holes 10.12, and the first and second mounting holes are bored. By forming the communication passage 26 by the hole portion 10.12 and the threaded portion 14, it is possible to easily remove and clean chips during the drilling operation, and the number of machining steps can be reduced compared to the conventional method.

Furthermore, since the first and second mounting holes 10.12 are formed to have the same center, it is possible to improve dimensional accuracy, improve assemblage, or improve performance, which is advantageous in practice. In addition, long bolts can be used as the first mounting bolts 16, and the spring constant can be made small. Further, changes in bolt axial force due to thermal expansion and explosive force of the cylinder head, that is, changes in elongation, can be reduced, ensuring stable fastening force, and improving sealing performance.

Figure 6.7 shows a second embodiment of the invention.

In this second embodiment, parts that perform the same functions as those in the first embodiment described above are given the same reference numerals and will be explained.

This second embodiment is characterized in that first and second slits 44.4G are formed in the first and second mounting bolts 40.42, respectively, and the first and second mounting holes 10.12 and 44.4G are formed in the first and second mounting bolts 40.42. 1. 2nd
a first formed by a mounting bolt 40, 42, respectively;
The second gap 48.50 and the first and second slits 44.4
6 constitutes a communication passage 52.

That is, by forming the inner diameters of the first and second mounting holes 10.12 larger than the inner diameter of the threaded part 14, the first
When the second mounting bolt 40.42 is screwed together, first and second gaps 48.50 are formed between the first and second mounting holes 10.12 and the first and second mounting bolts 40.42, respectively. .

Furthermore, two first slits 44 are formed at opposing positions on the distal end side of the first mounting bolt 40, as shown in FIG. As shown in the figure, two second slits 46 are formed at opposing positions.

Furthermore, a first hole 54 communicating with the first gap 4B is bored in a part of the cylinder head 4 at the peripheral edge of the head 402 of the first mounting bolt 40, and the head of the second mounting port 42 is provided with a first hole 54 that communicates with the first gap 4B. A second hole 56 communicating with the second gap 50 is bored in a part of the crank bearing 28 at the peripheral edge 42a.

Then, these first and second hole portions 54 and 56 and the first and second hole portions 54 and 56
The communication passage 52 is constituted by the gap 48, 50, the first and second slits 44, 46, and the space 24.

This allows the communication passage 52 to function as a blower gas passage or an oil drop passage, as in the first embodiment, which simplifies the configuration, contributes to miniaturization of the internal combustion engine, and reduces the work process. Can be installed with
This is practically advantageous.

Furthermore, by using the first and second slits 44.46 formed in the first and second mounting bolts 40.42 as the communication passage 52, the formation of the communication passage 52 is facilitated, and the cost can be reduced. It's something you get.

Furthermore, by having the communication passage 52, it is possible to easily remove and clean chips during drilling work, and
The number of processing steps can be reduced compared to conventional methods.

Furthermore, since the first and second mounting holes 10.12 have the same center, it is possible to improve dimensional accuracy, improve ease of assembly, or improve performance. Long bolts can be used as the mounting bolts 40, the spring constant can be kept small, and changes in bolt axial force due to thermal expansion and explosive force of the cylinder head, that is, changes in elongation, can be kept small, resulting in stable fastening force. can be ensured and the sealing performance can be improved.

8 to 10 show a third embodiment of the present invention.

The features of this third embodiment include a biasing member having a biasing force in the space 24 in the configuration of the above-mentioned first embodiment;
For example, the spring 60 is compressed.

That is, the spring 60 is compressed in the space 24,
The biasing force of the spring 60 is applied to the first and second mounting bolts 16 and 18.

Then, the urging force of the spring 60 functions to prevent the first and second mounting bolts 16 and 18 from loosening, and also reduces the stress on the carved portion 62 of the first mounting bolt 16, as shown in FIG. 9(b). The biasing stress distribution of the spring 60 as shown in FIG. 9(C) acts on the distribution, and as shown in FIG. This can be prevented and the service life of the carved portion 62 can be extended.

Further, like the first and second embodiments described above, the communication passage 26 can function as a blower gas passage or an oil dropping passage, and the blower gas passage or oil dropping passage can be made smaller or unnecessary, and the configuration can be simplified. This contributes to miniaturization of the internal combustion engine, and it can be installed in the second work step, which is advantageous in practice.

Furthermore, by having the communication passage 26, it is possible to easily remove and clean chips during drilling work, and
The number of processing steps can be reduced compared to conventional methods.

Furthermore, since the first and second mounting holes 10.12 have the same center, it is possible to improve dimensional accuracy, improve ease of assembly, or improve performance. Long bolts can be used as the mounting bolts 16, the spring constant can be kept small, and changes in bolt axial force due to thermal expansion and explosive force of the cylinder head, that is, changes in elongation, can be kept small, resulting in stable fastening force. can be ensured and sealing performance can be improved.

FIG. 11 shows a fourth embodiment of the invention.

The fourth embodiment is characterized in that a plastic deformation gauge 70 made of a metal member such as lead is provided in the space 24 in the configuration of the second embodiment.

Then, the axial force of the first and second mounting bolts 40, 42 can be measured using the plastic deformation gauge 70. That is, when measuring the axial force of the first mounting bolt 40, the length a under the neck of the first mounting bolt 40, the length a under the neck of this first mounting bolt 40, and the length of the plastic deformation gauge 70 are determined in advance. Measure the length C of the second mounting bolt 42 and keep it constant.
What is necessary is to measure the length b of the plastic deformation gauge 70 after fastening and use, detect the elongation of the first mounting bolt 40, and calculate the axial force of the second mounting bolt 42 based on the elongation of the first mounting bolt 40. It is. Also, if you perform the reverse process, the first
The axial force of the mounting bolt 40 can also be calculated.

Furthermore, by incorporating the plastic deformation gauge 70 into a general internal combustion engine, it becomes possible to detect necessary items such as the presence or absence of retightening, the amount of permanent elongation of the first and second mounting bolts 40, 42, or the axial force. This is extremely effective when assembling internal combustion engines.

Furthermore, similar to the first to third embodiments described above, the communication passage 52 can function as a blower gas passage or an oil drop passage, which simplifies the structure and contributes to miniaturization of the internal combustion engine, and also reduces the need for drilling. Chips can be easily removed and cleaned during machining work, and the number of machining steps can be reduced compared to conventional methods.

Furthermore, since the first and second mounting holes 10.12 have the same center, it is possible to improve dimensional accuracy, improve assemblability, or improve performance, which is advantageous in practical terms. Long bolts can be used as the mounting bolts 40, the spring constant can be kept small, and changes in bolt axial force due to thermal expansion and explosive force of the cylinder head, that is, changes in elongation, can be kept small, resulting in stable fastening force. can be ensured and sealing performance can be improved.

〔Effect of the invention〕

As explained in detail above, according to the present invention, the first mounting hole in the upper part of the cylinder block and the second mounting hole in the lower part of the cylinder block are provided in communication with each other, and the first mounting hole engages with the first mounting hole. At the same time, a second mounting tool that engages with the second mounting hole is installed, and a first mounting tool is installed to connect the upper and lower parts of the cylinder block.
Since the communication passage is provided in the second fitting, the communication passage can function as a blower gas passage or an oil drop passage, and the blower gas passage or oil drop passage can be made smaller or unnecessary, and the configuration is simplified. This contributes to the miniaturization of internal combustion engines and is advantageous in practice. Further, by having the communication passage, it is possible to easily remove and wash chips during drilling operations, and the number of processing steps can be reduced compared to the conventional method. Furthermore, if the first and second mounting holes are formed to have the same center, it is possible to improve dimensional accuracy, improve assemblability, or improve performance, which is advantageous in practice, and also 1 The spring constant of the mounting bolt can be made small,
Furthermore, changes in the bolt axial force due to thermal expansion and explosive force of the cylinder head, that is, changes in elongation, can be minimized, ensuring stable fastening force and improving sealing performance.

[Brief explanation of the drawing]

1 to 5 show a first embodiment of the present invention, FIG. 1 is an enlarged sectional view of main parts of a cylinder block during molding of an internal combustion engine, FIG. 2 is a plan view of the cylinder block, and FIG. 3 is a cylinder block FIG. 4 is an enlarged cross-sectional view of the cylinder block, and FIG. 5 is an enlarged cross-sectional view of the main part of the portion shown by the arrow (■) in FIG. Fig. 6.7 shows a second embodiment of the present invention, Fig. 6 is an enlarged cross-sectional view of the main part of the cylinder block during molding of an internal combustion engine, and Fig. 7 is a cross-sectional view taken along the line ■ to ■ in Fig. 6. be. 8 to 10 show a third embodiment of the present invention, and FIG. 8 is an enlarged cross-sectional view of main parts of a cylinder block during molding of an internal combustion engine;
Figure 9(a) is an enlarged view of the carved part of the first mounting bolt.
Figure (b) is a diagram showing the tightening stress distribution due to the first mounting bolt, Figure 9 (C) is a diagram showing the biasing stress distribution due to the spring, and Figure 10 is a diagram showing the tightening stress distribution of the first mounting bolt and the spring. FIG. FIG. 11 is an enlarged sectional view of a main part of a cylinder block during molding of an internal combustion engine, showing a fourth embodiment of the present invention. FIG. 12 is an enlarged sectional view of a cylinder block showing the prior art of the present invention. In the figure, 2 is a cylinder block, 4 is a cylinder head, 6 is an oil pan, 8-1.8-2.8-3 is a cylinder,
10 is a first mounting hole, 12 is a second mounting hole, 14 is a threaded part, 16 is a first mounting bolt, 18 is a second mounting bolt, 2
0 is the first through hole, 22 is the second through hole, 24 is the space, 2
6 is a communication passage, 28 is a crank bearing portion, and 30 is a crankshaft. Patent Applicant Suzuki Motor Co., Ltd. Agent Patent Attorney Yoshimi Nishigo 1, Indication of Case Patent Application No. 1986-108660 2, Name of Invention Cylinder Block Structure 3, Person Making Amendment Relationship with Case Patent Applicant Address 300 Takatsuka, Kami Village, Hamana District, Shizuoka Prefecture Name (2
08) i Gohon Jidosha Kogyo Co., Ltd. 4, Agent 101 03-292-4
411 (Representative) Address: 2-8-6 Kanda Ogawamachi, Chiyoda-ku, Tokyo, Subject of amendment (1) Drawing

Claims (1)

[Claims] 1. In a cylinder block that forms an internal combustion engine by mounting a cylinder head on the upper part and an oil pan on the lower part, a first mounting hole part for mounting the cylinder head in the upper part of the cylinder block and a crank bearing part in the lower part of the cylinder block. a second mounting hole to which the cylinder is attached, a first fixture that engages with the first mounting hole, and a second fixture that engages with the second mounting hole; A cylinder block structure characterized in that a communication passage is provided in the first and second fittings to communicate the upper and lower parts of the block.