JPWO2019142270A1 - Manufacturing method of internal combustion engine, internal combustion engine and connecting cylinder - Google Patents

Abstract

The internal combustion engine has excellent maintainability and recyclability, and the degree of freedom in designing the internal combustion engine is high. (1) A first connecting cylinder including two or more cylinder liners and a connecting portion for connecting the two or more cylinder liners to each other, and (2) a connecting cylinder main body provided with two or more cylinder bores. One of the connecting cylinders 10 selected from the group consisting of the portion and the second connecting cylinder including the coating film covering the inner peripheral surface provided with the cylinder bore of the connecting cylinder main body portion is installed on one end side of the crank chamber 62. Is formed, the cylinder head is assembled on the other end side, and the cylinder head is fitted into the hollow portion 64 of the cylinder block main body 60 provided with the hollow portion 64 penetrating from one end side to the other end side. A method for manufacturing an internal combustion engine for manufacturing an internal combustion engine 100, an internal combustion engine manufactured by the method, and a connecting cylinder used for the internal combustion engine.

Description

The present invention relates to a method for manufacturing an internal combustion engine, an internal combustion engine and a connecting cylinder.

Conventionally, as a cylinder block for the purpose of reducing the size and weight of a reciprocating multi-cylinder internal combustion engine, a so-called siamese type cylinder block having a structure formed by integrally connecting cylinder liners forming adjacent cylinder bores is known. Has been done. As a method for manufacturing such a cylinder block, for example, (1) an aggregate of cylinder liners is set in a mold at the time of casting the cylinder block, and then cast into the cylinder block main body to be fixed to the cylinder block main body. There are known methods and (2) a method of fixing an aggregate of cylinder liners to a cylinder body by fitting (Patent Documents 1 and 2). In the method of manufacturing a cylinder block described in Patent Documents 1 and 2, a plurality of cylinder liners are integrally molded and an aggregate of cylinder liners composed of one member is used.

Patent No. 2813947 Patent No. 4278125

On the other hand, the internal combustion engine needs to satisfy various performances according to the required specifications of the vehicle in which the internal combustion engine is used or a device other than the vehicle. For this purpose, when designing an internal combustion engine, it is advantageous that the degree of freedom is high. In addition, the internal combustion engine is also required to have excellent maintainability. Furthermore, in recent years, from the viewpoint of environmental load, internal combustion engines are also required to be recyclable. However, as a result of examination by the present inventors, in the method for manufacturing a cylinder block described in Patent Documents 1 and 2 and the internal combustion engine manufactured by using the method, all three of maintainability, recyclability and design freedom are all three. It turned out to be difficult to satisfy.

The present invention has been made in view of the above circumstances, and is a method for manufacturing an internal combustion engine, which is excellent in maintainability and recyclability of the internal combustion engine and has a high degree of freedom in designing the internal combustion engine, and an internal combustion engine manufactured by using the method. An object of the present invention is to provide a connecting cylinder used for the same.

The above object is achieved by the following invention. That is,
The method for manufacturing an internal combustion engine of the present invention includes (1) a first connecting cylinder including two or more cylinder liners and a connecting portion for connecting two or more cylinder liners to each other, and (2) two or more. Any connecting cylinder selected from the group consisting of a connecting cylinder main body provided with the cylinder bore of the above and a second connecting cylinder including a coating film covering the inner peripheral surface provided with the cylinder bore of the connecting cylinder main body. Is fitted into the hollow portion of the cylinder block body provided with a crank chamber formed on one end side, a cylinder head assembled on the other end side, and a hollow portion penetrating from one end side to the other end side. It is characterized in that an internal combustion engine is manufactured after at least the above.

In one embodiment of the method for manufacturing an internal combustion engine of the present invention, it is preferable that two or more cylinder liners and a connecting portion are integrally and inseparably formed.

In another embodiment of the method for manufacturing an internal combustion engine of the present invention, it is preferable that the connecting portion covers the entire outer peripheral surface of two or more cylinder liners.

In another embodiment of the method for manufacturing an internal combustion engine of the present invention, it is preferable that the material constituting the connecting portion is a material different from the material constituting the cylinder block main body.

In another embodiment of the method for manufacturing an internal combustion engine of the present invention, it is preferable that the material constituting the connecting cylinder main body is different from the material constituting the cylinder block main body.

In another embodiment of the method for manufacturing an internal combustion engine of the present invention, it is preferable that the fitting step is carried out by any fitting method selected from a clearance fit, an intermediate fit and a tight fit.

In another embodiment of the method for manufacturing an internal combustion engine of the present invention, the connecting cylinder is the first connecting cylinder, and a sliding surface forming step of forming a sliding surface by finishing the inner peripheral surface of the cylinder liner. Is preferably carried out only before the fitting step.

In another embodiment of the method for manufacturing an internal combustion engine of the present invention, the connecting cylinder is the first connecting cylinder, and the surface of the coating is formed after performing a coating forming step of forming a coating on the inner peripheral surface of the cylinder liner. It is preferable to carry out the sliding surface forming step of forming the sliding surface by finishing, and to carry out the sliding surface forming step only before the fitting step.

In another embodiment of the method for manufacturing an internal combustion engine of the present invention, the connecting cylinder is a second connecting cylinder, and the surface of the coating film covering the inner peripheral surface provided with the cylinder bore of the connecting cylinder body is finished. Therefore, it is preferable to carry out the sliding surface forming step for forming the sliding surface only before the fitting step.

In another embodiment of the method for manufacturing an internal combustion engine of the present invention, it is preferable that the fitting step is carried out by any fitting method selected from a clearance fit and an intermediate fit.

In another embodiment of the method for manufacturing an internal combustion engine of the present invention, it is preferable that the fitting step is carried out by crevice fitting.

In another embodiment of the method for manufacturing an internal combustion engine of the present invention, the connecting cylinder is the first connecting cylinder, and a sliding surface forming step of forming a sliding surface by finishing the inner peripheral surface of the cylinder liner. Is preferably carried out only after the fitting step.

In another embodiment of the method for manufacturing an internal combustion engine of the present invention, the connecting cylinder is the first connecting cylinder, and the surface of the coating is formed after performing a coating forming step of forming a coating on the inner peripheral surface of the cylinder liner. It is preferable to carry out the sliding surface forming step of forming the sliding surface by finishing, and to carry out the sliding surface forming step only after the fitting step.

In another embodiment of the method for manufacturing an internal combustion engine of the present invention, the connecting cylinder is a second connecting cylinder, and the surface of the coating film covering the inner peripheral surface provided with the cylinder bore of the connecting cylinder body is finished. Therefore, it is preferable that the sliding surface forming step for forming the sliding surface is carried out only after the fitting step.

In another embodiment of the method for manufacturing an internal combustion engine of the present invention, the sliding surface forming step is carried out in a state where the connecting cylinder is assembled to a jig simulating a cylinder block main body and a cylinder head, and at least the connecting cylinder is heated. It is preferable to be done.

In another embodiment of the method for manufacturing an internal combustion engine of the present invention, a coolant passage forming step of forming a coolant passage between two cylinder bores adjacent to each other of a connecting cylinder is performed at least before the fitting step. It is preferable to do so.

In another embodiment of the method for manufacturing an internal combustion engine of the present invention, the coolant passage is provided inside the end surface of the connecting cylinder on the side where the cylinder head is arranged, and each cylinder bore provided in the connecting cylinder. It is preferable that the cross-sectional shape of the coolant passage in a plane parallel to the center line of the cylinder is slit-shaped.

In another embodiment of the method for manufacturing an internal combustion engine of the present invention, it is preferable that the cylinder block body is manufactured by any method selected from casting and resin molding.

The internal combustion engine of the present invention has (1) a first connecting cylinder including two or more cylinder liners and a connecting portion for connecting two or more cylinder liners to each other, and (2) two or more cylinder bores. One end of a connecting cylinder selected from the group consisting of a connecting cylinder main body provided and a second connecting cylinder including a coating film covering an inner peripheral surface provided with a cylinder bore of the connecting cylinder main body. A cylinder block body is provided with at least a crank chamber formed on the side, a cylinder head assembled on the other end side, and a hollow portion penetrating from one end side to the other end side, and the connecting cylinder is a cylinder block. It is characterized in that it is detachably fitted to the hollow portion of the main body.

In another embodiment of the internal combustion engine of the present invention, it is preferable that the connecting cylinder is fitted to the hollow portion of the cylinder block body by any fitting method selected from a clearance fit and an intermediate fit.

In another embodiment of the internal combustion engine of the present invention, a coolant passage is provided between two cylinder bores of the connecting cylinders adjacent to each other, inside the end surface on the side where the cylinder head of the connecting cylinder is arranged. It is preferable that the cross-sectional shape of the coolant passage in a plane parallel to the center line of each cylinder bore provided in the connecting cylinder is slit-shaped.

In another embodiment of the internal combustion engine of the present invention, a fixing collar portion is provided on the outer peripheral surface of the connecting cylinder along a direction parallel to the center line of each cylinder bore provided in the connecting cylinder, and the cylinder block main body is provided. It is preferable that the inner peripheral surface of the hollow portion is provided with a guide groove for fitting with the fixing collar portion.

In another embodiment of the internal combustion engine of the present invention, fixing collars are provided on the outer peripheral surfaces of the connecting cylinders on both ends in the arrangement direction of the respective cylinder bores, and guide grooves are provided in the longitudinal direction of the opening of the hollow portion. It is preferable that the cylinder block body is provided on the inner peripheral surface of the hollow portion on both ends.

In another embodiment of the internal combustion engine of the present invention, a fixing flange portion is provided on the inner peripheral surface of the hollow portion of the cylinder block body along a direction parallel to the penetrating direction of the hollow portion, and is provided on the outer peripheral surface of the connecting cylinder. , It is preferable that a guide groove for fitting with the fixing flange portion is provided.

In another embodiment of the internal combustion engine of the present invention, fixing collars are provided on the inner peripheral surfaces of the hollow portion of the cylinder block body at both ends in the longitudinal direction of the opening of the hollow portion, and a guide groove is provided as a connecting cylinder. It is preferable that the cylinder bores are provided on the outer peripheral surfaces of the connecting cylinders on both ends in the arrangement direction of the cylinder bores.

In another embodiment of the internal combustion engine of the present invention, it is preferable that the internal combustion engine is a horizontally opposed engine.

In another embodiment of the internal combustion engine of the present invention, it is preferable that a coolant jacket is provided between the outer peripheral surface of the connecting cylinder and the inner peripheral surface of the hollow portion of the cylinder block body.

In another embodiment of the internal combustion engine of the present invention, the split collar that divides the coolant jacket into two or more portions is selected from the outer peripheral surface of the connecting cylinder and the inner peripheral surface of the hollow portion of the cylinder block body. It is preferable that the cylinder is provided on at least one of the surfaces.

In another embodiment of the internal combustion engine of the present invention, it is preferable that the fixing collar portion also has the function of the split collar portion.

In another embodiment of the internal combustion engine of the present invention, it is preferable that the split collar portion does not have a through hole penetrating in the width direction of the split collar portion.

In another embodiment of the internal combustion engine of the present invention, it is preferable that the split collar portion has a through hole penetrating in the width direction of the split collar portion and a closing member capable of closing the through hole.

In another embodiment of the internal combustion engine of the present invention, it is preferable that the through hole is closed by a closing member during operation of the internal combustion engine.

In another embodiment of the internal combustion engine of the present invention, it is preferable that the coolant jacket spacer is not arranged in the coolant jacket.

In another embodiment of the internal combustion engine of the present invention, the depth D of the coolant jacket is 1/2 times or less the total length L of the coolant jacket in the direction parallel to the center line of each cylinder bore provided in the connecting cylinder. Is preferable.

In another embodiment of the internal combustion engine of the present invention, the depth D of the coolant jacket is 1/2 times or less the total length L of the coolant jacket in the direction parallel to the center line of each cylinder bore provided in the connecting cylinder. It is preferable that the coolant jacket spacer is not arranged in the coolant jacket.

In another embodiment of the internal combustion engine of the present invention, a protrusion is provided on at least a part of the outer peripheral surface of the other end side (cylinder head side) of the outer peripheral surface of the connecting cylinder, and the tip portion of the protruding portion is a cylinder. It is preferable that the block body is in close contact with the inner peripheral surface of the other end side (cylinder head side) of the hollow portion.

Another embodiment of the internal combustion engine of the present invention is connected between the outer peripheral surface of the other end side (cylinder head side) of the connecting cylinder and the inner peripheral surface of the other end side (cylinder head side) of the cylinder block body. It is preferable that a fixing member for fixing the cylinder and the cylinder block main body to each other is provided.

In another embodiment of the internal combustion engine of the present invention, the first connecting cylinder has an annular outer shape in which the bore diameter of each cylinder liner is increased, and the cylinder is formed in the direction of the center line of each cylinder liner. The outer diameter D1 based on the center line of each cylinder liner in the first region consisting of the outer peripheral surface from the vicinity of the head side to the vicinity of the central portion is the respective cylinder liner in the second region consisting of the outer peripheral surface near the crank chamber side. A step larger than the outer diameter D2 with respect to the center line of the above, and parallel and continuous with the outer peripheral direction is formed between the first region and the second region, and further, with the first region. It is preferable that a coolant jacket is formed between the cylinder block body and the inner peripheral surface of the hollow portion.

In another embodiment of the internal combustion engine of the present invention, the second connecting cylinder has an annular outer peripheral shape in which the bore diameter of each cylinder bore is increased, and the cylinder head side is in the direction of the center line of each cylinder bore. The outer diameter D1 based on the center line of each cylinder bore in the first region consisting of the outer peripheral surface from the vicinity to the vicinity of the central portion sets the center line of each cylinder bore in the second region consisting of the outer peripheral surface near the crank chamber side. It is larger than the reference outer diameter D2, and a step parallel to and continuous with the outer peripheral direction is formed between the first region and the second region, and further, the first region and the cylinder block main body are formed. It is preferable that a coolant jacket is formed between the hollow portion and the inner peripheral surface of the hollow portion.

In another embodiment of the internal combustion engine of the present invention, the first region is provided with a collar portion that divides the first region into a region on the cylinder head side and a region on the crank chamber side, and is cooled by the collar portion. It is preferable that the liquid jacket is divided with respect to the center line direction of the cylinder liner or the cylinder bore.

The first connecting cylinder of the present invention is characterized by including two or more cylinder liners and a connecting portion for connecting the two or more cylinder liners to each other.

One embodiment of the first connecting cylinder of the present invention has an annular outer peripheral shape in which the bore diameter of each cylinder liner is expanded, and is centered from the vicinity of the cylinder head side in the center line direction of each cylinder liner. The outer diameter D1 based on the center line of each cylinder liner in the first region consisting of the outer peripheral surface up to the vicinity of the portion is based on the center line of each cylinder liner in the second region consisting of the outer peripheral surface near the crank chamber side. It is preferable that the outer diameter is larger than D2 and a step parallel to and continuous with the outer peripheral direction is formed between the first region and the second region.

The second connecting cylinder of the present invention is characterized by including a connecting cylinder main body provided with two or more cylinder bores and a coating film covering an inner peripheral surface provided with cylinder bores of the connecting cylinder main body. ..

A second embodiment of the connecting cylinder of the present invention has an annular outer peripheral shape in which the bore diameter of each cylinder bore is expanded, and in the direction of the center line of each cylinder bore, from the vicinity of the cylinder head side to the vicinity of the center portion. The outer diameter D1 based on the center line of each cylinder bore in the first region consisting of the outer peripheral surfaces up to is the outer diameter based on the center line of each cylinder bore in the second region consisting of the outer peripheral surface near the crank chamber side. It is preferable that the step is larger than D2 and a step parallel to and continuous with the outer peripheral direction is formed between the first region and the second region.

In one embodiment of the first and second connecting cylinders of the present invention, it is preferable that a collar portion is provided on the outer peripheral surface.

In another embodiment of the connecting cylinder of the first and second inventions, the first region is provided with a flange portion that divides the first region into a region on the cylinder head side and a region on the crank chamber side. Is preferable.

In other embodiments of the first and second connecting cylinders of the present invention, it is preferable that the collar portion does not have a through hole penetrating in the width direction of the collar portion.

In another embodiment of the connecting cylinder of the first and second inventions, it is preferable that the collar portion has a through hole penetrating in the width direction of the collar portion and a closing member capable of closing the through hole.

In another embodiment of the connecting cylinders of the first and second inventions, the coolant passage is located between the two cylinder bores of the connecting cylinders adjacent to each other, from the end surface on the side where the cylinder head of the connecting cylinder is arranged. It is preferable that the cross-sectional shape of the coolant passage in a plane parallel to the center line of each cylinder bore provided in the connecting cylinder is slit-shaped.

Other embodiments of the first and second connecting cylinders of the present invention preferably have no protrusions in the first region.

Other embodiments of the first and second connecting cylinders of the present invention preferably have no protrusions in the second region.

According to the present invention, there is provided a method for manufacturing an internal combustion engine, which is excellent in maintainability and recyclability of the internal combustion engine and has a high degree of freedom in designing the internal combustion engine, an internal combustion engine manufactured by using the method, and a connecting cylinder used therefor. be able to.

It is an external perspective view which shows an example of the 1st connection cylinder used in the manufacturing method of the internal combustion engine of this embodiment. It is an enlarged perspective view of the vicinity of the cylinder head side of the first connecting cylinder shown in FIG. FIG. 5 is an enlarged cross-sectional view showing an example of a cross-sectional structure between reference numerals III and III of the first connecting cylinder shown in FIG. It is an enlarged perspective view which shows an example of the vicinity of the cylinder head side of the 2nd connecting cylinder used in the manufacturing method of the internal combustion engine of this embodiment. FIG. 5 is an enlarged cross-sectional view showing an example of a cross-sectional structure between reference numerals V and V of the second connecting cylinder shown in FIG. It is an exploded perspective view which shows an example of the cylinder block main body used in the manufacturing method of the internal combustion engine of this embodiment by breaking a part of the cylinder block main body. It is an external perspective view which shows an example of the internal combustion engine using the 1st connecting cylinder manufactured by the manufacturing method of the internal combustion engine of this embodiment. 6 is a schematic cross-sectional view showing an example of a cross-sectional structure between reference numerals VIII and VIII of the internal combustion engine shown in FIG. 7. FIG. 3 is a schematic cross-sectional view showing an example of a cross-sectional structure between reference numerals IX and reference numeral IX of the first connecting cylinder shown in FIG. FIG. 5 is a schematic cross-sectional view showing an example of a cross-sectional structure between reference numerals XX of the second connecting cylinder shown in FIG. It is a schematic cross-sectional view which shows one modification of the 1st connecting cylinder shown in FIG. It is a schematic cross-sectional view which shows one modification of the internal combustion engine shown in FIG. It is a schematic cross-sectional view which shows the other modification of the internal combustion engine shown in FIG. It is a schematic end face view which shows an example of the cross-sectional shape of the coolant passage, and is the figure which shows the enlarged end face (ZX cross section) in the vicinity of the end face of the other end side (Z1 side) of the first connecting cylinder. Here, FIG. 14 (A) is an end view showing a cooling liquid passage having a circular cross-sectional shape, and FIG. 14 (B) is also an opening at the end surface on the other end side (Z1 side) of the connecting cylinder. FIG. 14 (C) is an end view showing a cooling liquid passage having a slit-shaped cross-sectional shape having a portion, and FIG. 14 (C) shows the inside (one end side (Z2 side)) of the end surface of the other end side (Z1 side) of the connecting cylinder 10. )) It is an end view which shows the cooling liquid passage which has a slit-like cross section shape provided. FIG. 3 is an external perspective view showing another modification of the first connecting cylinder shown in FIG. 1. FIG. 3 is an external perspective view showing another modification of the first connecting cylinder shown in FIG. 1. FIG. 3 is an external perspective view showing another modification of the first connecting cylinder shown in FIG. 1. It is a top view which shows an example of the cylinder block main body used in combination with the 1st connecting cylinder shown in FIG.

The manufacturing method of the internal combustion engine, the internal combustion engine and the connecting cylinder of the present embodiment will be described below with reference to the drawings. In the following description, the X, Y, and Z directions shown in the figure are orthogonal to each other. Here, the X direction is the alignment direction of the cylinder bores, and the Y direction is orthogonal to the alignment direction of the cylinder bores and also orthogonal to the center line C of the cylinder bores (in the first connecting cylinder, the center lines C of the cylinder bores and the cylinder liner). It is a direction, and the Z direction is a direction parallel to the center line C of the cylinder bore. Further, in the X direction, the X1 side is opposite to the X2 side, in the Y direction, the Y1 side is opposite to the Y2 side, and in the Z direction, the Z1 side (cylinder head side) is the Z2 side. The direction is opposite to (cylinder chamber side).

<Manufacturing method of internal combustion engine>
In the method for manufacturing an internal combustion engine of the present embodiment, (1) a first connecting cylinder including two or more cylinder liners and a connecting portion for connecting the two or more cylinder liners to each other, and (2) two. Any connection selected from the group consisting of a connecting cylinder main body provided with the above cylinder bore and a second connecting cylinder including a coating film covering the inner peripheral surface provided with the cylinder bore of the connecting cylinder main body. Use a cylinder.

1 to 3 are schematic views showing an example of a connecting cylinder used in the method for manufacturing an internal combustion engine of the present embodiment, and specifically, a diagram illustrating an example of a first connecting cylinder. Here, FIG. 1 shows an external perspective view of the first connecting cylinder, and FIG. 2 shows an enlarged perspective view of the vicinity of the cylinder head side of the first connecting cylinder. Further, FIG. 3 is an enlarged cross-sectional view showing an example of a cross-sectional structure in the vicinity of the cylinder head side of the first connecting cylinder, and is a cross-sectional structure in which the first connecting cylinder is cut between reference numerals III to III in FIG. XY cross-sectional structure) is shown.

The first connecting cylinders 10A1 (10A, 10) illustrated in FIGS. 1 to 3 are provided with four cylinder bores 20, and each cylinder bore 20 has its own center line C in the same plane (XZ plane). It is provided along the X direction so as to be located above. Further, the first connecting cylinder 10A1 has four cylinder liners 40 and a connecting portion 42 for connecting the four cylinder liners 40 to each other. In the example shown in FIGS. 1 to 3, the connecting portion 42 is provided so as to cover at least the entire outer peripheral surface 40A of each of the four cylindrical cylinder liners 40, and the bore of each cylinder liner 40. It has an annular outer peripheral shape with an expanded diameter Db. Further, one cylinder liner 40 adjacent to each other in the X direction and the other cylinder liner 40 are arranged apart from each other at a certain distance so that the outer peripheral surfaces 40A do not come into contact with each other. That is, the space between the two cylinder liners 40 adjacent to each other is tightly filled with the material constituting the connecting portion 42. Further, the end faces of the cylinder liner 40 on the cylinder head side and the crank chamber side are also covered by the connecting portion 42. However, the end face of the cylinder liner 40 may not be covered by the connecting portion 42, either or both of the end faces on the cylinder head side and the end face on the crank chamber side.

4 to 5 are schematic views showing another example of the connecting cylinder used in the method for manufacturing the internal combustion engine of the present embodiment, and specifically, is a diagram for explaining an example of the second connecting cylinder. .. Here, FIG. 4 shows an enlarged perspective view of the vicinity of the cylinder head side of the second connecting cylinder. Further, FIG. 5 is an enlarged cross-sectional view showing an example of a cross-sectional structure in the vicinity of the cylinder head side of the second connecting cylinder, and is a cross-sectional structure (XY cross-sectional structure) in which the connecting cylinder is cut between reference numerals V and V in FIG. ) Is shown.

The outer peripheral shape of the second connecting cylinder 10B (10) illustrated in FIGS. 4 to 5 is the same as that of the first connecting cylinder 10A1 illustrated in FIG. The second connecting cylinder 10B is also provided with four cylinder bores 20, and each cylinder bore 20 is provided along the X direction so that its center line C is located on the same plane (XZ plane). Have been placed. Further, the second connecting cylinder 10B includes a connecting cylinder main body 50 provided with four cylinder bores 20 and a coating 52 covering the inner peripheral surface 50B provided with the cylinder bore 20 of the connecting cylinder main body 50. In the examples shown in FIGS. 4 to 5, the connecting cylinder main body 50 has an annular outer peripheral shape in which the bore diameter Db of the four circular hole-shaped cylinder bores 20 is expanded.

The first connecting cylinder 10A1 illustrated in FIGS. 1 to 3 shows a case where four cylinder liners 40 are provided, but the number of cylinder liners 40 is not particularly limited as long as it is 2 or more, and is generally used. Can be selected within the range of about 2 to 8. Further, in the second connecting cylinder 10B illustrated in FIGS. 4 to 5, the case where four cylinder bores 20 are provided is shown, but the number of cylinder bores 20 is not particularly limited as long as it is 2 or more, and is general. Can be selected within the range of about 2 to 8.

In the method for manufacturing an internal combustion engine of the present embodiment, the internal combustion engine is manufactured by at least undergoing a fitting step of fitting the connecting cylinder 10 as illustrated in FIGS. 1 to 5 to the cylinder block main body.

Here, as illustrated in FIG. 6, the cylinder block main body 60A (60) is formed with a crank chamber 62 on one end side (Z2 side), and a cylinder head is assembled on the other end side (Z1 side). It has a structure provided with a hollow portion 64 penetrating from one end side to the other end side. Then, in the fitting step, the connecting cylinder 10 is fitted into the hollow portion 64. Further, after carrying out the fitting step, the internal combustion engine is completed by further carrying out various other steps. Other steps include, for example, a step of assembling the cylinder head on the cylinder head side (Z1 side) of the cylinder block main body 60 in which the connecting cylinder 10 fitted and fixed in the hollow portion 64 is arranged.

In the fitting step, the connecting cylinder 10 can be fitted into the hollow portion 64 of the cylinder block main body 60 by any fitting method selected from a clearance fit, an intermediate fit, and a tight fit. Here, in the specification of the present application, the "clearance fit" is a fitting in which a gap is generated between the members even when the tolerance of each member to be fitted is taken into consideration, and the "tight fit" is a fitting. Even if the tolerance of each member to be fitted is taken into consideration, a tightening allowance is generated between the members, and the "intermediate fit" is a fitting when considering the tolerance of each member to be fitted. It is a fit (intermediate fit between a clearance fit and a tight fit) in which there may be both a gap between the members and a tightening allowance.

The fitting method by tight fitting is not particularly limited. For example, a cylinder in a state in which the connecting cylinder 10 in a cooled state is fitted into a hollow portion 64 of the cylinder block main body 60 by cooling fitting and the connecting cylinder 10 is heated. Examples thereof include shrink fitting and strong press fitting to fit the hollow portion 64 of the block body 60. Further, the fitting method using an intermediate fit is not particularly limited, but for example, after fitting in a state where the fitting portion is slippery by using a lubricant or the like, or after performing high-precision positioning, the connecting cylinder Fitting using a jig made of a material softer than 10 (for example, driving with a resin-made or wooden hammer) can be mentioned. Further, the connecting cylinder 10 is connected to the cylinder block main body 60 by a clearance fit. When fitting into the hollow portion 64, a material that is easily deformed or easily flowed, including a resin material, a rubber material, a fibrous material such as glass fiber, and a paste-like material, is placed between both members as necessary. Matching may be carried out.

Which fitting method should be selected can be selected according to the required design specifications of the internal combustion engine 100 and the like. When it is desired to firmly fix the connecting cylinder 10 to the cylinder block main body 60, fitting by tightening is preferable. When fitting by a tight fit is preferable, for example, when the internal combustion engine 100 is attached to a device such as an automobile or when assembled, such as a V-type engine or a horizontally opposed engine. , Usually, a case where the center line C of the cylinder bore is greatly inclined or orthogonal to the vertical direction can be exemplified.

On the other hand, when the internal combustion engine 100 is attached to a device such as an automobile or when assembled, the internal combustion engine 100 has a configuration in which the vertical direction and the center line C of the cylinder bore are parallel or substantially parallel to each other, as in a series engine or the like. In the case of, it is easy to stably fix the connecting cylinder 10 in the cylinder block main body 60 without causing a positional deviation of the connecting cylinder 10 in a direction orthogonal to the center line C of the cylinder bore. In such cases, fitting by crevice fitting is also suitable. Further, even if the internal combustion engine 100 has a configuration in which the center line C of the cylinder bore is normally greatly inclined or orthogonal to the vertical direction in a state where the internal combustion engine 100 is attached to a device such as an automobile. When assembling the internal combustion engine 100 (particularly preferably, the period from immediately before attaching the connecting cylinder 10 to the cylinder block main body 60 to the completion of assembling the cylinder head), the vertical direction and the center line C of the cylinder bore are parallel or substantially parallel. In the case where the cylinders are arranged so as to form a gap, fitting by a clearance fit is also suitable. Further, as compared with the tight fit and the intermediate fit, in the clearance fit, when the internal combustion engine 100 is disassembled, the joint portion between the connecting cylinder 10 and the cylinder block main body 60 is less likely to be damaged. It is also advantageous in terms of use.

Further, (i) when it is desired to suppress deformation of the connecting cylinder 10, the cylinder bore 20, the cylinder block body 60 or the hollow portion 64 after fitting, or (ii) at the time of repair / maintenance or disposal of the internal combustion engine 100. If it is desired to easily remove the connecting cylinder 10 from the cylinder block main body 60, it is preferable to fit the connecting cylinder 10 by a clearance fit. Further, when it is desired to obtain an intermediate effect between the fitting by the tight fit and the fitting by the clearance fitting, the fitting by the intermediate fitting is preferable.

Further, when the connecting cylinder 10 is fitted into the hollow portion 64, the outer peripheral surface 10S on one end side (Z2 side) of the connecting cylinder 10 is set as a tapered surface in order to improve the positioning and insertability of the connecting cylinder 10 with respect to the hollow portion 64. It is also preferable to do so.

FIG. 7 shows an external perspective view showing an example of an internal combustion engine manufactured by the method for manufacturing an internal combustion engine of the present embodiment, and FIG. 8 shows a case where the internal combustion engine shown in FIG. 7 is cut between reference numerals IV and IV. It is a schematic cross-sectional view which shows an example of the cross-sectional structure (YZ cross-sectional structure). In the internal combustion engine shown in FIGS. 7 and 8, the description of other main members constituting the internal combustion engine other than the connecting cylinder and the cylinder block main body is omitted.

The internal combustion engine 100A (100) shown in FIGS. 7 and 8 has a connecting cylinder 10 and a cylinder block main body 60, and the connecting cylinder 10 is a portion of the cylinder block main body 60 on one end side of a hollow portion 64. It is removably fitted at (fitting portion 64J). In the examples shown in FIGS. 7 and 8, the first connecting cylinder 10A1 illustrated in FIGS. 1 to 3 is used as the connecting cylinder 10, but instead of the first connecting cylinder 10A1, a second connecting cylinder 10A1 is used. The connecting cylinder 10B can be used, or the connecting cylinder 10 having a flange portion 16 as illustrated in FIGS. 11 and 15 to 17 described later can be used. Further, in the examples shown in FIGS. 7 and 8, the cylinder block main body 60A shown in FIG. 6 is used as the cylinder block main body 60, but when the connecting cylinder 10 having the flange portion 16 is used, the figure described later will be shown. A cylinder block main body 60B (60) as illustrated in 13 can also be used.

On the other hand, in a general internal combustion engine having a structure in which a plurality of cylinder liners are cast in a cylinder block, even if a part of the internal combustion engine needs to be repaired or replaced, the internal combustion engine including the cylinder liner and the cylinder block is included. It is necessary to handle the entire main part of the engine. In addition to this, in a general internal combustion engine, two or more kinds of materials having different materials (for example, a material constituting a cylinder liner and a material constituting a cylinder block for casting a cylinder liner) are inseparably integrated. It is configured. For this reason, when recycling is attempted for each material type, it is necessary to separate each material type by utilizing the difference in the melting temperature of the material. This point is the same in the internal combustion engine disclosed in Patent Document 1, which has a structure in which an aggregate of cylinder liners is cast in a cylinder block main body.

On the other hand, in the method for manufacturing an internal combustion engine of the present embodiment, as illustrated in FIGS. 7 and 8, the connecting cylinder 10 is fixed to the cylinder block main body 60 by fitting the connecting cylinder 10 into the hollow portion 64. It is done by. Therefore, the connecting cylinder 10 once fixed to the cylinder block main body 60 can be easily removed from the cylinder block main body 60. Therefore, when the internal combustion engine 100 is maintained, the connecting cylinder 10 can be removed from the cylinder block main body 60, and either one or both of the connecting cylinder 10 and the cylinder block main body 60 can be repaired or replaced separately. Therefore, the internal combustion engine 100 manufactured by the method for manufacturing the internal combustion engine of the present embodiment is excellent in maintainability.

In addition to this, when the internal combustion engine 100 is disposed of, the connecting cylinder 10 and the cylinder block main body 60, which are the main members constituting the internal combustion engine 100, can be easily separated and disposed of separately. Here, the cylinder block main body 60 used in the manufacturing method of the internal combustion engine of the present embodiment is usually a member manufactured by casting, resin molding, or the like (a member made of one kind of material which is inseparable as a whole). Consists of.

Therefore, the cylinder block main body 60 removed from the internal combustion engine 100 can be recycled as it is without further separation processing or the like. For example, if the cylinder block main body 60 is a casting manufactured using an aluminum alloy, cast iron, or the like, the cylinder block main body 60 can be melted and reused. Therefore, the internal combustion engine 100 manufactured by the method for manufacturing an internal combustion engine according to the present embodiment is also excellent in recyclability. It is particularly preferable that the cylinder block main body 60 is usually composed of a member made of one kind of material which is inseparable as a whole, but if it has substantially the same recyclability as such a member, it is preferable. The structure of the cylinder block main body 60 is not limited to the case where the whole is composed of a member made of one kind of inseparable material.

If any one of the connecting cylinder 10 and the cylinder block main body 60 constituting the internal combustion engine 100 to be disposed of can withstand reuse, one member is reused and only the other member is disposed of. It is also possible.

From the viewpoint that the connecting cylinder 10 and the cylinder block main body 60 can be easily separated and disassembled at the time of recycling or disposal of the internal combustion engine 100, the connecting cylinder 10 is provided in the hollow portion 64 of the cylinder block main body 60 with a clearance fit. It is preferably fitted by any fitting method selected from the intermediate fit, and more preferably by a clearance fit.

On the other hand, when the internal combustion engine 100 in which the connecting cylinder 10 is fitted to the hollow portion 64 of the cylinder block main body 60 by a tight fit is recycled or disposed of, the process is the reverse of cold fitting and / or shrink fitting. It is preferable to carry out. That is, when the connecting cylinder 10 side is cooled and / or the cylinder block main body 60 side is heated, the connecting cylinder 10 and the cylinder block main body 60 can be easily separated and disassembled. Such a method of disassembling the internal combustion engine 100 is also applied to the internal combustion engine 100 in which the connecting cylinder 10 is fitted to the hollow portion 64 of the cylinder block main body 60 by an intermediate fit or a clearance fit, if necessary. You may.

Further, in the conventional general method for manufacturing an internal combustion engine in which a cylinder liner and a cylinder block are integrated by casting a cylinder liner to manufacture an internal combustion engine, only the cylinder liner portion or a portion in the vicinity thereof is defective after casting. Even if a defect is found only on the cylinder block side, it is necessary to dispose of the entire member in which the cylinder liner and the cylinder block are integrated. On the other hand, in the method for manufacturing an internal combustion engine of the present embodiment, the internal combustion engine 100 is manufactured by preparing two parts (connecting cylinder 10 and cylinder block main body 60) and combining them. Therefore, even if a defective defect is found in any of the parts after the fitting process is completed, only the part in which the defective defect is found can be discarded. That is, therefore, even if defective defects occur, the waste loss in the manufacturing process can be further reduced.

Further, the internal combustion engine is required to satisfy various performances such as output, fuel consumption, small size and light weight according to the required specifications of the vehicle in which the internal combustion engine is used or a device other than the vehicle. In addition to this, particularly important characteristics for the internal combustion engine such as output and fuel consumption tend to be greatly influenced by the material and structure in the vicinity of the cylinder bore. Therefore, it is important for the internal combustion engine to have a high degree of freedom in design so that various performances can be flexibly satisfied, and in particular, a high degree of freedom in designing the vicinity of the central portion (near the cylinder bore) of the internal combustion engine. ..

On the other hand, the main part of the connecting cylinder 10 used in the method for manufacturing an internal combustion engine of the present embodiment is composed of a combination of two types of members. That is, the main part of the first connecting cylinder 10A is composed of a combination of the cylinder liner 40 and the connecting part 42, and the main part of the second connecting cylinder 10B is the connecting cylinder main body 50 and the coating 52. It is composed of a combination with and. Therefore, by appropriately changing the combination of the materials and shapes of these two types of members, it is easy to satisfy various performances according to the required specifications of the vehicle in which the internal combustion engine is used or the equipment other than the vehicle. In addition to this, since the main part of the entire internal combustion engine 100 is composed of a connecting cylinder 10 and a cylinder block main body 60 which are separate and independent members, a combination of materials and shapes of these two types of members is required. By appropriately changing the above, it is easy to satisfy various performances according to the required specifications of the vehicle in which the internal combustion engine is used or the equipment other than the vehicle.

Therefore, by casting the cylinder liner into the cylinder block, a general internal combustion engine having a structure in which both members are integrally formed, or a plurality of cylinder liners are integrally molded and composed of one member. The internal combustion engine 100 manufactured by the method for manufacturing an internal combustion engine of the present embodiment has a higher degree of design freedom than the internal combustion engine disclosed in Patent Documents 1 and 2 that uses an aggregate of cylinder liners. Therefore, the internal combustion engine 100 can easily meet a wide range of required specifications.

The internal combustion engine 100 is not limited to a specific design specification, and can be flexibly designed based on various required specifications or technical concepts. As a design example of the internal combustion engine 100, for example, the following design example is given as a basic technical concept.

(Design example 1)
a) Connecting cylinder 10 used for the internal combustion engine 100: First connecting cylinder 10A.
b) Material constituting the cylinder liner 40: A material having excellent sliding characteristics (wear resistance, seizure resistance, low friction resistance) relative to the connecting portion 42 is used.
c) Material constituting the connecting portion 42: A material having a relatively low density (light weight) and high thermal conductivity (heat dissipation) with respect to the material constituting the cylinder liner 40 is used.
In this design example 1, it is possible to provide an internal combustion engine 100 having excellent sliding characteristics, light weight, and heat dissipation.

(Design example 2)
a) Connecting cylinder 10 used for the internal combustion engine 100: First connecting cylinder 10A.
b) Material constituting the connecting portion 42: A material having high strength is used.
In this design example 2, the strength of the connecting portion 42 is increased. Therefore, it becomes easy to reduce the wall thickness of the cylinder liner 40 and the wall thickness between the two adjacent cylinder bores 20, and as a result, the weight of the internal combustion engine 100 can be reduced. Alternatively, if the wall thickness between the two adjacent cylinder bores 20 is not thinned, the strength required for the first connecting cylinder 10A is secured when the cooling medium flow path is provided between the two adjacent cylinder bores 20. At the same time, the volume of the cooling medium flow path can be increased. In addition, it becomes possible to suppress bore deformation due to an increase in in-cylinder pressure due to engine combustion.

(Design example 3)
A second connecting cylinder 10B is used as the connecting cylinder 10 used for the internal combustion engine 100.
In this design example 3, the sliding characteristics can be ensured by the coating film 52 whose mass is substantially negligible as compared with the cylinder liner 40. For this reason, in an internal combustion engine, a structural portion near the portion where the cylinder bores are arranged: that is, a portion composed of a cylinder liner and a casting member covering the cylinder liner in a conventional general internal combustion engine, and FIGS. A portion composed of a second connecting cylinder 10B as compared with a portion composed of a first connecting cylinder 10A having a cylinder liner 40 and a connecting portion 42 provided so as to cover the entire outer peripheral surface 40A of the cylinder liner 40. It is easy to significantly reduce the mass and volume. Therefore, the internal combustion engine 100 can be significantly reduced in weight and size.

(Design example 4)
a) Connecting cylinder 10 used for the internal combustion engine 100: First connecting cylinder 10A.
b) Material constituting the connecting portion 42 and the cylinder liner 40: A high-strength metal material is used.
c) Material constituting the cylinder block main body 60: A material lighter than a metal material such as a resin material or an organic-inorganic composite material In this design example 4, the strength of the first connecting cylinder 10A is high, so that even a high in-cylinder pressure can be obtained. It is possible to suppress bore deformation. Further, since the cylinder block main body 60 constituting the main part of the internal combustion engine 100 is made of a lightweight material, the weight of the internal combustion engine 100 as a whole can be reduced.

(Design example 5)
a) Connecting cylinder 10 used for the internal combustion engine 100: First connecting cylinder 10A.
b) Material constituting the connecting portion 42 and the cylinder liner 40: A high-strength metal material is used.
c) Simplification of the structure of the cylinder block main body 60 (for example, the groove 66 is omitted in the cylinder block main body 60A shown in FIG. 6).
In this design example 5, since the strength of the first connecting cylinder 10A is high, it is possible to suppress the bore deformation even at a high cylinder pressure. Further, since the structure of the cylinder block main body 60 constituting the main part of the internal combustion engine 100 is simplified, the productivity of the internal combustion engine 100 is improved.

Next, the connecting cylinder 10 and the cylinder block main body 60 used in the method for manufacturing an internal combustion engine of the present embodiment will be described.

First, in the first connecting cylinder 10A, the two or more cylinder liners 40 and the connecting portion 42 may be formed inseparably (in other words, non-detachable), or may be configured to be removable. Good. (A) When the first connecting cylinder 10A is a member formed so that two or more cylinder liners 40 and the connecting portion 42 are integrally inseparable, each cylinder liner 40 and the connecting portion 42 are formed. An interface (joining interface) for joining both members is formed between them. (B) Further, when the first connecting cylinder 10A is a member in which two or more cylinder liners 40 and the connecting portion 42 are detachably formed, between each cylinder liner 40 and the connecting portion 42. Is formed with an interface (contact interface) in which both members are simply in contact with each other. In both cases (a) and (b), each cylinder liner 40 and the connecting portion 42 are discontinuous members. Further, the connecting portion 42 may be provided so as to cover the entire outer peripheral surface 40A of the cylinder liner 40 as illustrated in FIGS. 1 to 3, and covers only a part of the outer peripheral surface 40A of the cylinder liner 40. It may be provided so as to do so. The selection and combination of these aspects can be appropriately selected according to the required specifications of the internal combustion engine 100 to be manufactured.

For example, a) After arranging two or more cylinder liners 40 in the mold, the molten metal is poured into the mold, and the two or more cylinder liners 40 are cast with a casting material such as cast iron or aluminum alloy. Two or more cylinder liners 40, b) after arranging two or more cylinder liners 40 in the mold, by injection or injection of a molten resin material into the mold, etc. It is possible to obtain the first connecting cylinder 10A in which the connecting portion 42 is integrally formed inseparably. In this case, by appropriately selecting the shape of the mold, the connecting portion 42 may cover the entire outer peripheral surface 40A of the cylinder liner 40, or may cover only a part of the outer peripheral surface 40A of the cylinder liner 40. it can.

Further, two or more circular through holes are provided, and the cylinder liner 40 is fitted and fixed to the through holes of the connecting portion 42 having a continuous annular shape in which the center lines of the through holes are parallel to each other. It is also possible to obtain a first connecting cylinder 10A in which two or more cylinder liners 40 and a connecting portion 42 are detachably configured. In this case, for example, by appropriately selecting the length of the connecting portion 42 in the center line direction, the connecting portion 42 can cover the entire outer peripheral surface 40A of the cylinder liner 40, and the outer peripheral surface 40A of the cylinder liner 40 can be covered. It is also possible to cover only a part of.

However, it is preferable that the connecting portion 42 is formed by casting (for example, die casting, gravity casting, etc.) rather than using a member having a shape formed in an annular shape in advance. In this case, the number of parts can be reduced when manufacturing the first connecting cylinder 10A. In addition to this, when the connecting portion 42 is formed inseparably from the cylinder liner 40 by casting as compared with the case where a member having a shape formed in an annular shape in advance is used as the connecting portion 42, the connecting portion 42 and the cylinder Since the heat transfer resistance at the interface with the liner 40 can be reduced, it is easy to improve the cooling performance of the internal combustion engine 100. When the connecting portion 42 is formed by casting, in order to improve the joint strength between the connecting portion 42 and the cylinder liner 40, a protrusion having a height of about 0.1 mm to 1.5 mm is formed on the outer peripheral surface 40A of the cylinder liner 40. Or a groove or a recess having a depth of about 0.1 mm to 1.5 mm may be provided.

The wall thickness of the cylinder liner 40 can be appropriately selected, but is generally about 1.0 mm to 4.0 mm. Further, a more preferable shape and structure of the connecting cylinder 10 will be described later.

On the other hand, with respect to the second connecting cylinder 10B, for example, after the connecting cylinder main body 50 is manufactured by casting, a film 52 is formed so as to cover the inner peripheral surface 50B provided with the cylinder bore 20 of the connecting cylinder main body 50. To do. A known film forming method such as a thermal spraying method can be appropriately used for forming the film 52. The thickness of the coating film 52 can be appropriately selected, but is generally within about 0.02 mm to 0.2 mm. In this case, for example, when the thermal spraying method is adopted as the film forming method of the film 52, the thickness of the film 52 is preferably about 0.1 mm to 0.2 mm, and PVD (Physical Vapor Deposition) is used as the film forming method of the film 52. When the method or the CVD (Chemical Vapor Deposition) method is adopted, the thickness of the coating film 52 is preferably about 0.02 mm to 0.03 mm. Further, a plating method can also be used as a method for forming the film 52. In this case, the thickness of the coating film 52 is preferably about 0.02 mm to 0.2 mm. Further, examples of the coating film 52 made of a plating film include a Cr-based plating film and a plating film containing Ni and SiC (so-called nickel plating film).

In the first connecting cylinder 10A, the material constituting the connecting portion 42 may be the same material as the material constituting the cylinder block main body 60, but is different from the material constituting the cylinder block main body 60. Is particularly preferable. Similarly, in the second connecting cylinder 10B, the material constituting the connecting cylinder main body 50 may be the same material as the material constituting the cylinder block main body 60, but the material constituting the cylinder block main body 60 may be used. It is particularly preferred that they are of different materials.

In the specification of the present application, "two kinds of materials are different from each other" means that a) the composition of each material is fundamentally different, such as aluminum alloy and steel, and b) the same composition system. In terms of materials, for example, even if two types of aluminum alloys are used, if one has a high Al content and the other has a low Al content, and the quantitative compositions are different, c). In materials with the same composition system and the same quantitative composition, there are differences in the degree of crystalline-aluminous property, different types of crystal phases, or other structural structures between one material and the other material. Or, d) a single material, such as plastic and fiber reinforced plastic, in which one material and the other material contain the same material X, but one material consists only of the material X. , When the other material is a composite material containing the other material Y in addition to the material X, and the like.

The material constituting the main portion of the connecting cylinder 10 (the connecting portion 42 in the first connecting cylinder 10A and the connecting cylinder main body 50 in the second connecting cylinder 10B) is different from the material constituting the cylinder block main body 60. By doing so, the degree of freedom in designing the entire internal combustion engine 100 can be further improved. Therefore, for example, it becomes extremely easy to manufacture an internal combustion engine 100 having various specifications as illustrated in the following (1) to (3).
(1) An internal combustion engine having specifications that reduce the cost and weight of the cylinder block body 60 by using a material having a relatively high rigidity with respect to the cylinder block body 60 as a material constituting the main part of the connecting cylinder 10. 100.
(2) Internal combustion engine with specifications that reduce the burden on the cooling system under high load by using a material with relatively high thermal conductivity with respect to the main part of the connecting cylinder 10 as the material constituting the cylinder block main body 60. Institution 100.
(3) By using a material having a relatively low thermal conductivity with respect to the main part of the connecting cylinder 10 as a material constituting the cylinder block main body 60, the temperature of the coolant during low load and warm air is accelerated to accelerate fuel consumption. Internal combustion engine 100 with improved specifications.

Examples of the material constituting the connecting portion 42 or the connecting cylinder main body 50 include metal materials such as an aluminum alloy (preferably a high-rigidity type aluminum alloy), a magnesium alloy, and steel, and form the cylinder block main body 60. As the material, an organic-inorganic composite material containing a metal material such as an aluminum alloy or a magnesium alloy, a resin material, or a resin and an inorganic material (for example, an inorganic filler such as glass fiber or carbon fiber is added to a heat-resistant resin matrix such as phenol resin. Dispersed material, etc.) and the like.

Further, from the viewpoint of suppressing deformation of the cylinder bore 20 during operation of the internal combustion engine 100, the coefficient of thermal expansion of the material constituting the cylinder block main body 60 is the heat of the material constituting the connecting portion 42 of the first connecting cylinder 10A. The coefficient of thermal expansion is equal to or greater than the coefficient of thermal expansion, and the coefficient of thermal expansion of the material constituting the cylinder block body 60 is equal to or greater than the coefficient of thermal expansion of the material constituting the connecting cylinder body 50 of the second connecting cylinder 10B. It is preferable to have.

Further, examples of the material constituting the cylinder liner 40 include cast iron materials such as flake graphite cast iron, and as the material constituting the coating film 52, various known hard materials can be used without limitation. For example, the coating film 52 may be used. When the film is formed by the thermal spraying method, Fe type, WC type and the like can be mentioned, and when the film 52 is formed by the PVD method or the CVD method, C type, Cr type and the like can be mentioned. Further, the layer structure of the coating film 52 is not particularly limited, and may be, for example, a single-layer structure, or a laminated structure in which different materials or different crystal phases are combined.

On the other hand, in the cylinder block main body 60 used in the method for manufacturing an internal combustion engine of the present embodiment, as illustrated in FIGS. 6 to 8, a crank chamber 62 is formed on one end side and a cylinder head is assembled on the other end side. At the same time, the structure is not particularly limited as long as it is provided with a hollow portion 64 penetrating from one end side to the other end side and has a structure capable of fitting the connecting cylinder 10 into the hollow portion 64. The cylinder block main body 60 can be manufactured by appropriately using a known method, but is preferably manufactured by casting or resin molding. Specific examples of other manufacturing methods other than casting and resin molding include, for example, hot pressing treatment or HIP (Hot Isostatic Pressing) treatment using raw material powder, laminating of layers made of raw material powder, and laser sintering. A laser sintering process in which the above steps are alternately repeated can be mentioned. Here, when the cylinder block main body 60 is manufactured by casting or resin molding, there are merits described below.

First, when a member is manufactured by casting, volume shrinkage occurs in the process of cooling the molten metal injected into the mold. Therefore, as the volume of the member increases, defects such as cavities are likely to occur. On the other hand, compared to the conventional method for manufacturing an internal combustion engine in which a cylinder block is formed by casting a cylinder liner with an aluminum alloy or the like, the method for manufacturing an internal combustion engine of the present embodiment is a connection manufactured separately. The internal combustion engine 100 is manufactured by mechanically fitting the cylinder 10 and the cylinder block main body 60. Therefore, the volume of the cylinder block main body 60 can be significantly reduced as compared with the volume of the cylinder block of the conventional internal combustion engine. Therefore, when the cylinder block main body 60 is manufactured by casting, it becomes easy to suppress the occurrence of defects such as cavities due to volume shrinkage. In addition to this, various measures to suppress these defects (for example, making the wall thickness of the members manufactured by casting as constant as possible) are taken as compared with the case of casting the cylinder block of a conventional internal combustion engine. You don't have to actively adopt it. Therefore, it is possible to increase the degree of freedom in designing the shape, structure, and casting process of the cylinder block main body 60. For example, when the coolant jacket is provided on the cylinder block body 60 as compared with the coolant jacket provided on the cylinder block of a conventional internal combustion engine, or the inner peripheral surface 64S of the hollow portion 64 of the cylinder block body 60 and the connecting cylinder 10 When a coolant jacket is provided between the outer peripheral surface 10S and the outer peripheral surface 10S, it is extremely easy to form a coolant jacket having a shallower depth from the other end side. It should be noted that these points are substantially the same when the cylinder block main body 60 is manufactured by resin molding in which volume shrinkage occurs in the process of cooling the molten resin material injected or injected into the mold.

In the method for manufacturing an internal combustion engine of the present embodiment, in addition to the fitting step, a step of assembling various parts such as a cylinder head after the connecting cylinder 10 is attached to the cylinder block main body 60 and an inner circumference of the cylinder bore 20 A sliding surface forming step of forming a sliding surface by finishing processing such as honing processing, wrapping processing, dimple processing, or a cooling liquid passage between two cylinder bores 20 adjacent to each other of the connecting cylinder 10. Various steps such as a forming step can be appropriately carried out as needed.

Here, in the specification of the present application, the "sliding surface" refers to a piston or a piston ring mounted on a groove provided on an outer peripheral surface of the piston when the completed internal combustion engine 100 is operated. It means a moving surface. Then, in the manufacturing process of the internal combustion engine 100 of the present embodiment, once the formation of the "sliding surface" is completed, no further finishing process is performed on the "sliding surface". The "sliding surface" is any surface as long as it is a surface that slides in contact with the piston or the piston ring mounted in the groove provided on the outer peripheral surface of the piston when the completed internal combustion engine 100 is operated. It may be a surface formed for various purposes. For example, (a) a finishing process whose main purpose is to correct the deformation of the cylinder bore 20 or (b) a finishing process whose main purpose is to adjust the wall thickness of the cylinder liner 40 or the film thickness of the coating film 52. Along with this, a sliding surface may be formed incidentally and inevitably. However, the sliding surface is preferably a surface that has been finished for the main purpose of improving / improving seizure resistance and suppressing oil consumption.

The "sliding surface" may be formed by performing processing on the inner peripheral surface of the cylinder bore 20 only once, or may be formed by performing processing a plurality of times. When the "sliding surface" is formed by performing the processing a plurality of times, the "sliding surface" means only the surface formed after the final finishing process is performed, and the final process. The process of performing the finishing process is called the "sliding surface forming process". In addition, the process of performing processing other than the final finishing processing (first processing to final processing-1st processing) is called a "roughing surface forming process".

The surface morphology of the "sliding surface" varies depending on the finishing method and is not particularly limited. For example, regarding the surface shape, a cross hatch (fine mesh streaks or grooves or diagonal parallel lines) (A surface on which fine streaks or grooves are formed) can be exemplified, and the surface roughness can be exemplified by an arithmetic average roughness Ra of about 0.1 μm to 0.8 μm.

The sliding surface forming step of forming the sliding surface by finishing the inner peripheral surface 20B of the cylinder bore 20 can be performed at an arbitrary timing in the manufacturing process of the internal combustion engine 100, but can be roughly classified into (I) fitting. The sliding surface forming step is carried out before the joining step, or (II) the sliding surface forming step is carried out after the fitting step. In the above processes (I) and (II), another step may be carried out between the fitting step and the sliding surface forming step, if necessary.

(I) When the sliding surface forming step is carried out before the fitting step, for example, the following three modes can be mentioned. First, when the connecting cylinder 10 is the first connecting cylinder 10A, the sliding surface forming step of forming the sliding surface by finishing the inner peripheral surface 40B of the (Ia) cylinder liner 40 is performed in the fitting step. A slide that forms a sliding surface by finishing the surface of the coating after performing the coating formation step of forming a coating on the inner peripheral surface 40B of the cylinder liner 40 (Ib) only in the front. The moving surface forming step can be carried out, and the sliding surface forming step can be carried out only before the fitting step. Further, when the connecting cylinder 10 is the second connecting cylinder 10B, the surface 52B of the coating film 52 covering the inner peripheral surface 50B provided with the cylinder bore 20 of the (Ic) connecting cylinder main body 50 is finished. The sliding surface forming step for forming the sliding surface can be carried out only before the fitting step.

Here, when the sliding surface forming step is carried out before the (I) fitting step, the fitting step is preferably carried out by a fitting method other than the tight fit, and specifically, the clearance fit. Alternatively, it is more preferable to carry out by an intermediate fit. When the fitting process is carried out by squeezing, the cylinder bore 20 of the connecting cylinder 10 is easily deformed, and as a result, poor airtightness between the piston and the sliding surface of the cylinder bore 20 is likely to occur. This is because there is an increased possibility that the sliding surface forming step needs to be performed again to correct the deformation of the cylinder bore 20 after the fitting step. In order to prevent such a problem more reliably, it is particularly preferable that the fitting step is carried out by crevice fitting.

Further, as a case where the sliding surface forming step is carried out after the fitting step (II), for example, the following three modes can be mentioned. First, when the connecting cylinder 10 is the first connecting cylinder 10A, the sliding surface forming step of forming the sliding surface by finishing the inner peripheral surface 40B of the (IIa) cylinder liner 40 is performed in the fitting step. A slide that forms a sliding surface by finishing the surface of the coating after performing the coating formation step of forming a coating film on the inner peripheral surface 40B of the cylinder liner 40 (IIb) only afterwards. The moving surface forming step can be carried out, and the sliding surface forming step can be carried out only after the fitting step. When the connecting cylinder 10 is the second connecting cylinder 10B, (IIc) the surface 52B of the coating film 52 covering the inner peripheral surface 50B provided with the cylinder bore 20 of the connecting cylinder main body 50 is finished. The sliding surface forming step of forming the sliding surface can be carried out only after the fitting step.

Here, when the sliding surface is formed by performing machining on the inner peripheral surface of the cylinder bore 20 a plurality of times, the roughing machined surface forming step may be carried out before the fitting step. It may be carried out after the fitting step, or a part may be carried out before the fitting step and the rest may be carried out after the fitting step.

The sliding surface forming step is performed after the cylinder block is formed by casting the cylinder liner in a conventional general internal combustion engine in which the cylinder block is formed by casting the cylinder liner. .. Therefore, it is necessary to inspect the sliding surface after performing the sliding surface forming step, and if the inspection result is judged to be defective, dispose of the entire cylinder block in which the cylinder liner is cast. ..

On the other hand, when the sliding surface forming step is carried out before the fitting step (I), the sliding surface forming step is carried out in the state of the connecting cylinder 10 alone. Therefore, after performing the sliding surface forming step, the sliding surface is inspected, and if the inspection result is determined to be defective, only the connecting cylinder 10 may be disposed of. Therefore, even if defective defects occur, the waste loss in the manufacturing process can be further reduced.

When the sliding surface forming step is carried out before the fitting step (I), the sliding surface forming step may be carried out as it is for the connecting cylinder 10 alone, but the connecting cylinder 10 is connected to the cylinder block. The sliding surface forming step may be carried out in a state where the main body 60 and the cylinder head are assembled to a jig simulating. When the cylinder head is further assembled to the internal combustion engine 100 in which the connecting cylinder 10 is fitted to the cylinder block main body 60, the cylinder bore 20 is easily deformed when the cylinder head is assembled. Therefore, when the sliding surface forming step is performed using a jig in consideration of such deformation, it becomes easy to further improve the processing accuracy of the sliding surface.

Further, when the sliding surface forming step is performed using a jig, it is preferable to carry out the step in a state where at least the connecting cylinder 10 is heated, and more preferably it is carried out in a state where the connecting cylinder 10 and the jig are heated. .. As a result, the optimum sliding surface shape can be created while keeping the temperature close to the temperature of the member during operation. In this case, the temperature of the member to be heated is particularly preferably a temperature as close as possible to the average temperature during operation of the internal combustion engine 100. The heating method is not particularly limited, and examples thereof include a method of carrying out the sliding surface forming step in a state where hot water (for example, hot water of 30 ° C. to 95 ° C.) is flowed through the coolant jacket. The coolant jacket referred to here includes (i) a coolant jacket formed in the connecting cylinder 10, (ii) an outer peripheral surface of the connecting cylinder 10 and an inner peripheral surface of a jig imitating the cylinder block body 60. Examples thereof include a (pseudo) coolant jacket formed between the two, or a (pseudo) coolant jacket formed in a jig imitating the (iii) cylinder block main body 60.

Whether the sliding surface forming step is performed before or after the fitting step can be appropriately selected according to the entire manufacturing process of the internal combustion engine 100, the specifications of the internal combustion engine 100, and the like. For example, in the manufacture of the internal combustion engine 100, it is difficult to use a connecting cylinder 10 or a cylinder block body 60 having high dimensional accuracy, high strength and being hard to be deformed, or to apply a pressing force that causes deformation of the cylinder bore 20 when assembling the cylinder head. In some cases, the sliding surface forming step may be carried out before the (I) fitting step, and in the opposite case, the sliding surface forming step may be carried out after the (II) fitting step.

Further, when it is desired to improve the cooling capacity of the peripheral portion of the cylinder bore 20 of the internal combustion engine 100 to be manufactured, a coolant passage forming step of forming a coolant passage between two cylinder bores 20 adjacent to each other of the connecting cylinder 10 is carried out. It is preferable to do so. In this case, the coolant passage forming step may be carried out after the fitting step, but more preferably before the fitting step. In any case, another step may be performed between the coolant passage forming step and the fitting step, if necessary. In the coolant passage forming step, the coolant passage can be formed by using various processing means such as a water jet, a laser, an end mill, and a cutter in addition to the commonly used drill. ..

Therefore, when (i) a cooling liquid passage forming step is performed after the fitting step, or (ii) a cooling liquid is formed in a conventional method for manufacturing an internal combustion engine in which a cylinder block is formed by casting a cylinder liner. When the coolant passage forming step is performed before the fitting step, the degree of freedom in processing and forming the coolant passage can be increased as compared with the case where the cooling passage forming step is carried out. This is because in the cases shown in (i) and (ii) above, when the coolant passage is formed, it can be dug only from the cylinder head side in order to form the coolant passage. When the coolant passage forming step is performed before the joining step, it can be seen from either the cylinder head side (the end face side of the connecting cylinder 10 on the cylinder head side) or the cylinder head side (the outer peripheral surface 10S of the connecting cylinder 10). This is because it is possible to dig. In addition, since the degree of freedom in selecting the drilling direction is large, it is easy to use a processing means other than the commonly used drill.

Therefore, when the cooling design around the cylinder bore 20 is performed, it becomes easy to realize a more ideal design. For example, it is also possible to form a coolant passage that is normally impossible in the cases shown in (i) and (ii) above, that is, to form a coolant passage that extends parallel to the end face of the connecting cylinder 10 on the cylinder head side. It will be possible. Further, the cross-sectional shape of the coolant passage in the plane (ZX plane) parallel to the center line C of each cylinder bore 20 provided in the connecting cylinder 10 is a simple circular shape as shown in FIG. 14 (A). In addition to the coolant passage 30A (30), various shapes can be selected. For example, it has a slit-shaped cross-sectional shape in which the ratio (Lz / Lx) of the maximum width Lz in the direction parallel to the center line C (Z direction) with respect to the maximum width Lx in the arrangement direction (X direction) of the cylinder bores 20 is larger than 1. A coolant passage can be formed. The ratio (Lz / Lx) is preferably, for example, 2 to 10, and more preferably 2.5 to 8. The values of Lz and Lx are not particularly limited, but for example, Lz is preferably in the range of 5 mm to 30 mm, and Lx is preferably in the range of 2 mm to 4 mm.

The coolant passage 30 having such a slit-shaped cross-sectional shape is (a) for a coolant having an opening 34 continuous in the Y direction on the end surface 36 on the other end side (Z1 side) of the connecting cylinder 10. Passage 30B (30) (FIG. 14 (B)) or (b) Inside (one end side (Z2 side)) of the other end side (Z1 side, side on which the cylinder head is arranged) of the connecting cylinder 10 30C (30) (FIG. 14C) for the coolant provided in the above can also be mentioned. However, the coolant passage 30C having a slit-shaped cross-sectional shape as illustrated in FIG. 14 (C) is inside (one end side (Z2)) of the end surface 36 on the other end side (Z1 side) of the (a) connecting cylinder 10. By providing it on the side)), it is possible to increase the degree of freedom in cooling design around the cylinder bore 20. When forming the coolant passage 30C having a slit-shaped cross-sectional shape as illustrated in FIG. 14C, it is preferable to carry out the coolant passage forming step at least before the fitting step. This is because, with such a process sequence, the degree of freedom in selecting the processing means and processing method required to form the coolant passage 30C is extremely high.

Further, in the case where a processing error occurs in the coolant passage 30, even when the coolant passage forming step is performed at any timing before or after the fitting step, it is discarded as compared with the case shown in (ii) above. Only the connecting cylinder 10 may be disposed of. Therefore, it is possible to reduce the waste loss due to processing mistakes.

The coolant passage 30 may be formed between two cylinder bores 20 adjacent to each other, but in the first connecting cylinder 10A, it is usually between the outer peripheral surfaces 40A of the two cylinder liners 40 adjacent to each other. In the second connecting cylinder 10B, which is formed in the region (region M1 shown in FIGS. 3 and 14), usually between the outer peripheral side surfaces 52A of the coating film 52 forming the inner peripheral surface 20B of two adjacent cylinder bores 20. (Region M2 shown in FIG. 5).

<Internal combustion engine, connecting cylinder and cylinder block body>
Next, a more preferable shape and structure of the internal combustion engine 100 manufactured by the method for manufacturing the internal combustion engine of the present embodiment, and the connecting cylinder 10 and the cylinder block main body 60 used for the internal combustion engine 100 will be described below. As illustrated in FIGS. 7 and 8, the internal combustion engine 100 manufactured by the method for manufacturing an internal combustion engine of the present embodiment includes at least a connecting cylinder 10 and a cylinder block main body 60, and the connecting cylinder 10 is a cylinder block. It has a structure in which it is detachably fitted to the hollow portion 64 of the main body 60.

Here, in the internal combustion engine 100 of the present embodiment, the coolant jacket provided so as to surround the outer peripheral side of the cylinder bore 20 is (i) inside the connecting cylinder 10 (inside the outer peripheral surface 10S of the connecting cylinder 10), (ii). ) Between the outer peripheral surface 10S of the connecting cylinder 10 and the inner peripheral surface 64S of the hollow portion of the cylinder block main body 60, or (iii) inside the cylinder block main body 60 (outer peripheral side of the inner peripheral surface 64S of the hollow portion 64). , Can be provided in any of. However, in the case shown in (i) above, since the coolant jacket is provided on the connecting cylinder 10, the structure of the connecting cylinder 10 is complicated, and in the case shown in (iii) above, the coolant jacket is provided on the cylinder block body 60. Since it is provided, the structure of the cylinder block main body 60 is complicated. Therefore, it is preferable that the coolant jacket is provided between the connecting cylinder 10 and the cylinder block main body 60. Further, it is preferable not to provide a coolant jacket in the connecting cylinder 10 because the manufacturability is likely to be lowered due to the complicated structure.

On the other hand, in the case shown in (ii) above, the internal combustion engine 100 is compared with a conventional internal combustion engine in which a cylinder block having a coolant jacket is formed in the cylinder block by casting a cylinder liner. It is not necessary to use a mold having a complicated shape in manufacturing. Therefore, the manufacturability of the internal combustion engine 100 is improved.

Further, in the internal combustion engine 100 of the present embodiment, it is necessary to bring the flow of the coolant in the coolant jacket close to the ideal state so that the temperature distribution of the sliding surface of the cylinder bore 20 becomes a desired state. A coolant jacket spacer may be further arranged in the coolant jacket accordingly. Also in the case shown in (ii) above, either the first aspect in which the coolant jacket spacer is arranged in the coolant jacket and the second aspect in which the coolant jacket spacer is not arranged in the coolant jacket is selected. Although possible, the second aspect is more preferred. The reason for this is as follows. That is, the shape and depth of the coolant jacket are determined by the shape of the outer peripheral surface 10S of the connecting cylinder 10 and the inner peripheral surface 64S of the hollow portion of the cylinder block main body 60. Since the connecting cylinder 10 and the cylinder block main body 60 are separate and independent members, the degree of freedom in shape design of both members is extremely high. Therefore, the degree of freedom in designing the shape and depth of the coolant jacket is extremely high. Therefore, even in the second aspect, it is extremely easy to bring the flow of the coolant in the coolant jacket close to the ideal state so that the temperature distribution of the sliding surface of the cylinder bore 20 is in a desired state. Further, as a result, the number of parts constituting the internal combustion engine 100 can be reduced and the structure of the internal combustion engine 100 can be simplified.

When the coolant jacket is provided between the outer peripheral surface 10S of the connecting cylinder 10 and the inner peripheral surface 64S of the hollow portion 64 of the cylinder block main body 60, as illustrated in FIG. 8, the outer peripheral surface 10S of the connecting cylinder 10 A coolant jacket 70 is provided between the other end side (cylinder head side) and the other end side (cylinder head side) of the inner peripheral surface 64S of the hollow portion 64 of the cylinder block main body 60. Further, one end side of the outer peripheral surface 10S of the connecting cylinder 10 and one end side of the inner peripheral surface 64S of the hollow portion 64 of the cylinder block main body 60 are in contact with each other, so that the connecting cylinder 10 is hollowed out in the cylinder block main body 60. A portion on one end side of the portion 64 (fitting portion 64J) is a portion that is detachably fitted.

In any of the cases (i) to (iii) above, the depth D (length in the Z direction) of the coolant jacket 70 is not particularly limited and can be appropriately selected according to the design specifications of the internal combustion engine 100, but is connected. When the total length L of the connecting cylinder 10 in the center line C direction of each cylinder bore 20 provided in the cylinder 10 is used as a reference, for example, the depth D is within the range of about 1/6 to 5/6 times the total length L. Can be selected as appropriate. For example, in the case of an internal combustion engine 100 having specifications for selectively and intensively cooling a portion of the cylinder bore 20 near the cylinder head side, the depth D may be in the range of 1/6 to 1/2 times the total length L. The range may be 1/6 to 1/3 times, or 1/6 to 1/4 times. From the viewpoint that the shallow coolant jacket 70 having a depth D of 1/2 times or less the total length L can be easily formed, (ii) is the most preferable among the above (i) to (iii). Further, when it is desired to bring the flow of the coolant in the coolant jacket 70 closer to the ideal state without arranging the coolant jacket spacer in the coolant jacket 70, the depth D is 1/2 times the total length L. It is preferable to form the following shallow coolant jacket 70.

The inner peripheral surface 64S of the fitting portion 64J and the inner peripheral surface 64S of the fitting portion 64J are provided on the inner peripheral surface 64S of the fitting portion 64J so that the coolant (water or the like) in the coolant jacket 70 does not leak to the crank chamber 62 side. For example, a sealing member such as an O-ring is arranged between the outer peripheral surface 10S of the opposing connecting cylinder 10. Further, at least one surface selected from the inner peripheral surface 64S of the fitting portion 64J and the outer peripheral surface 10S of the connecting cylinder 10 facing the inner peripheral surface 64S of the fitting portion 64J has a peripheral surface, if necessary. A groove continuous in the direction may be provided, and a seal member may be attached to this groove.

Further, in order to improve the strength and deformation of the cylinder head side of the cylinder bore 20 and improve the reliability of the internal combustion engine 100 at the time of high supercharging, (a1) the other end side of the outer peripheral surface 10S of the connecting cylinder 10 A protruding portion may be provided on at least a part of the outer peripheral surface 10S of the cylinder block body 60, and the tip end portion of the protruding portion may be substantially brought into close contact with the inner peripheral surface 64S on the other end side of the hollow portion 64 of the cylinder block main body 60. Further, from the same viewpoint, (a2) a protruding portion may be provided on at least a part of the inner peripheral surface 64S on the other end side of the hollow portion 64 of the cylinder block main body 60. Alternatively, as illustrated in FIGS. 7 and 8, (b) between the outer peripheral surface 10S on the other end side of the connecting cylinder 10 and the inner peripheral surface 64S on the other end side of the hollow portion 64 of the cylinder block main body 60. , A fixing member 80 for fixing the connecting cylinder 10 and the cylinder block main body 60 to each other may be provided. From the viewpoint of facilitating the manufacture of the connecting cylinder 10, it is more preferable to use the fixing member 80 than to provide a protruding portion on the outer peripheral surface 10S of the connecting cylinder 10 or the inner peripheral surface 64S of the cylinder block main body 60. ..

As illustrated in (a1) and (a2) above, when the fitting portion is formed by the other end side portion of the connecting cylinder 10 and the other end side portion of the cylinder block main body, the fitting portion is fitted. The method may be any fitting method selected from clearance fit, intermediate fit and tight fit. Further, as illustrated in (b), the other end side portion of the connecting cylinder 10 and the fixing member 80 form a first fitting portion, and the other end side portion of the cylinder block main body 60 and the fixing member 80 are formed. When forming the second fitting portion with, the fitting method of the first fitting portion and the second fitting portion is any fitting selected from crevice fit, intermediate fit and tight fit. A combined method may be used. However, from the viewpoint of suppressing deformation of the cylinder bore 20 during assembly of the internal combustion engine 100, a crevice fit or an intermediate fit is preferable, and a crevice fit is particularly preferable. Such a fitting method is particularly suitable when (I) a process of carrying out a sliding surface forming step before the fitting step is adopted when assembling the internal combustion engine 100.

When the fixing member 80 is used, as illustrated in FIGS. 1, 2, 4, and 8 on the outer peripheral surface 10S on the other end side of the connecting cylinder 10 so that the fixing member 80 does not deviate from a predetermined position. A groove 12 is provided, and the inner peripheral surface 64S on the other end side of the hollow portion 64 of the cylinder block main body 60 also corresponds to the groove 12 provided on the outer peripheral surface 10S of the connecting cylinder 10 as illustrated in FIGS. 6 and 8. A groove 66 may be provided at a position where the groove 66 is formed. In this case, by fitting one end of the fixing member 80 into the groove 12 and fitting the other end into the groove 66, between the outer peripheral surface 10S of the connecting cylinder 10 and the inner peripheral surface 64S of the hollow portion 64 of the cylinder block main body 60. The fixing member 80 can be arranged in. The groove 12 may be formed in advance in the connecting cylinder 10, and the groove 66 may also be formed in advance in the cylinder block main body 60. However, it is preferable to form the grooves 12 and 66 after fitting the connecting cylinder 10 in which the groove 12 is not formed and the cylinder block main body 60 in which the groove 66 is not formed.

In the example shown in FIG. 8, the cross-sectional shape of the fixing member 80 is square, and the interface (first interface) between the fixing member 80 and the connecting cylinder 10 and the fixing member 80 and the cylinder block body 60 (Second interface) is parallel to the center line C of the cylinder bore 20. Therefore, even if the fixing member 80 is arranged between the connecting cylinder 10 and the cylinder block main body 60 by crevice fitting when assembling the internal combustion engine 100, it is near the top dead center of the piston when the internal combustion engine 100 is in operation. When the vicinity of the other end side (Z1 side) of the connecting cylinder 10 thermally expands, the gap between the first interface and the second interface may disappear. In this case, the other end side (Z1 side) of the connecting cylinder 10 is pressed by the fixing member 80, and as a result, the cylinder bore 20 is easily deformed. However, if the dimensions are designed so that the minimum clearance at the first interface and the second interface becomes large in order to prevent such deformation, it becomes difficult to firmly fix the other end side (Z1 side) of the connecting cylinder 10.

In order to suppress the above-mentioned dilemma, the cross-sectional shape of the fixing member 80 may be, for example, an inverted trapezoidal shape. In this case, the interface between the fixing member 80 and the connecting cylinder 10 is inclined so as to approach the center line C of the cylinder bore 20 from one end side (Z2 side) to the other end side (Z1 side) of the cylinder block main body 60. The interface between the fixing member 80 and the cylinder block main body 60 is inclined so as to be separated from the center line C of the cylinder bore 20 from one end side (Z2 side) to the other end side (Z1 side) of the cylinder block main body 60. Therefore, when the vicinity of the other end side (Z1 side) of the connecting cylinder 10 near the top dead center of the piston is thermally expanded during the operation of the internal combustion engine 100, the push applied from the connecting cylinder 10 side to the fixing member 80 side. The pressure can be easily relieved by sliding the fixing member 80 toward the other end side (Z1 side).

The material constituting the fixing member 80 is not particularly limited, and for example, various metal materials such as aluminum alloys, magnesium alloys, and iron alloys such as steel, resin materials, organic-inorganic composite materials, and ceramics such as alumina are used. it can.

The connecting cylinder 10 used in the method for manufacturing an internal combustion engine of the present embodiment includes, for the first connecting cylinder 10A, two or more cylinder liners 40 and a connecting portion 42 for connecting two or more cylinder liners 40 to each other. The shape and structure thereof are not particularly limited as long as they include, and for the second connecting cylinder 10B, a connecting cylinder main body 50 provided with two or more cylinder bores 20 and a cylinder bore 20 of the connecting cylinder main body 50 are provided. The shape and structure thereof are not particularly limited as long as they include a coating film 52 that covers the inner peripheral surface 50B provided with the above. Similarly, in the cylinder block main body 60, a crank chamber 62 is formed on one end side (Z2 side), a cylinder head is assembled on the other end side (Z1 side), and a hollow portion penetrating from one end side to the other end side. As long as 64 is provided, the shape and structure thereof are not particularly limited.

On the other hand, the connecting cylinder 10 and the cylinder block main body 60 have a shape that is easier to manufacture while achieving both excellent maintainability, excellent recyclability, and a high degree of freedom in design of the internal combustion engine 100 manufactured by using them. It is preferable to have a further structure. However, the connecting cylinder 10 and the cylinder block main body 60 are used to manufacture the internal combustion engine 100 by combining both members. Therefore, even if the shape and structure of the connecting cylinder 10 are determined only in consideration of the manufacturability of the connecting cylinder 10, the shape and structure of the cylinder block main body 60 used in combination with the connecting cylinder 10 becomes complicated and the cylinder block main body 60 becomes complicated. The manufacturability of the internal combustion engine 100 may be lowered, and further, the manufacturability of the internal combustion engine 100 may be lowered. Further, this point is the same when the shape and structure of the cylinder block main body 60 are determined only in consideration of the manufacturability of the cylinder block main body 60. Therefore, in consideration of these points, the present inventors have found that the shape and structure described below are suitable as the shape and structure of the connecting cylinder 10 and the cylinder block main body 60 used in combination with the connecting cylinder 10. ..

First, the first connecting cylinder 10A has two or more cylinder liners 40 as illustrated in FIG. 9 in which the cross-sectional structure (YZ cross-sectional structure) between the reference numerals IX and IX shown in FIGS. 1 and 3 is illustrated. It includes two or more connecting portions 42 for connecting two or more cylinder liners 40 to each other, and has an annular outer peripheral shape in which the bore diameter Db of each cylinder liner 40 is expanded. Then, in the direction of the center line C of each cylinder liner 40, the outer diameter D1 with reference to the center line C of each cylinder liner 40 on the outer peripheral surface (first region 10S1) from the vicinity of the cylinder head side to the vicinity of the center portion is , Larger than the outer diameter D2 with respect to the center line C of each cylinder liner 40 on the outer peripheral surface (second region 10S2) near the crank chamber side, and between the first region 10S1 and the second region 10S2. Is preferably formed with a step 14 parallel to and continuous with the outer peripheral direction.

Further, regarding the second connecting cylinder 10B, as illustrated in FIG. 10 in which the cross-sectional structure (YZ cross-sectional structure) between reference numerals XX shown in FIG. 5 is illustrated, a connection in which two or more cylinder bores 20 are provided. It includes a cylinder body 50 and a coating 52 that covers the inner peripheral surface 50B provided with the cylinder bore 20 of the connecting cylinder body 50, and has an annular outer peripheral shape in which the bore diameter Db of each cylinder bore 20 is expanded. .. Then, in the direction of the center line C of each cylinder bore 20, the outer diameter D1 with reference to the center line C of each cylinder bore 20 on the outer peripheral surface (first region 10S1) from the vicinity of the cylinder head side to the vicinity of the central portion is a crank. It is larger than the outer diameter D2 with respect to the center line C of each cylinder bore 20 on the outer peripheral surface (second region 10S2) near the chamber side, and is between the first region 10S1 and the second region 10S2. It is preferable that a step 14 parallel to and continuous with the outer peripheral direction is formed. The outer peripheral shape of the second connecting cylinder 10B shown in FIG. 10 is the same as the outer peripheral shape of the first connecting cylinder 10A shown in FIG.

Further, with respect to the cylinder block main body 60, it is preferable that the opening shape of the hollow portion 64 is an annular shape corresponding to the outer peripheral shape of the connecting cylinder 10 illustrated in FIGS. 1, 9 and 10. Specifically, as illustrated in FIGS. 6 and 8, the inner peripheral surface 64S of the hollow portion 64 has a first step 68A continuous in the circumferential direction and a first step 68A continuous in the circumferential direction. The opening width of the hollow portion 64 on the inner peripheral surface 64S1 on the other end side (cylinder head side) of the first step 68A, which has a second step 68B provided on one end side (cylinder chamber side). The opening width W2 of the hollow portion 64 on the inner peripheral surface 64S2 of W1 and one end side (cylinder chamber side) of the first step 68A and the other end side (cylinder head side) of the second step 68B, and the second step. It is preferable that the opening width W3 of the hollow portion 64 on the inner peripheral surface 64S3 on one end side (cylinder chamber side) of 68B satisfies the relationship of W1> W2> W3. The opening widths W1, W2, and W3 mean the opening width in any direction regardless of the opening width in the lateral direction (Y direction) and the opening width in the longitudinal direction (X direction) of the opening shape of the hollow portion 64. That is, it is preferable to satisfy the relationship of W1> W2> W3 regardless of the lateral direction (Y direction) and the longitudinal direction (X direction). The opening widths W1sm, W2sm, and W3sm shown in FIG. 8 mean the maximum opening width of the opening shape of the hollow portion 64 in the lateral direction (Y direction), and the opening widths W1, W2, and W3, respectively. It corresponds. Further, the opening widths W2sm and W3sm are equal to the outer diameters D1 and D2 of the connecting cylinder 10, respectively.

Here, the connecting cylinder 10 provided with the step 14 on the outer peripheral surface 10S is fitted into the hollow portion 64 of the cylinder block main body 60 provided with the first step 68A and the second step 68B on the inner peripheral surface 64S. In the case, in the center line C direction, the second step 68B provided on the inner peripheral surface 64S of the cylinder block main body 60 and the step 14 provided on the outer peripheral surface 10S of the connecting cylinder 10 are fitted so as to coincide with each other. .. At the same time, on the crank chamber side of the first step 68A, the inner peripheral surface 64S2 of the cylinder block main body 60 and the outer peripheral surface 10S (first region 10S1) of the connecting cylinder 10 are in direct contact or in close contact with each other via a seal member. At the same time, the inner peripheral surface 64S3 of the cylinder block main body 60 and the outer peripheral surface 10S (second region 10S2) of the connecting cylinder 10 are in close contact with each other directly or via a seal member. That is, of the outer peripheral surface 10S of the connecting cylinder 10, the portion of the first region 10S1 on the second region 10S2 side and the second region 10S2 form a fitting portion corresponding to the fitting portion 64J of the cylinder block main body 60. To do. Therefore, the coolant jacket 70 formed between the inner peripheral surface 64S1 of the cylinder block main body 60 and the outer peripheral surface 10S (first region 10S1) of the connecting cylinder 10 on the cylinder head side of the first step 68A. It is possible to prevent the coolant inside from leaking to the crank chamber 62 side.

Regarding the capacity of the coolant jacket 70 that controls the cooling characteristics in the cylinder bore 20 and the vicinity of the cylinder bore 20 and the formation position of the coolant jacket 70 in the center line C direction, for example, when focusing on the cylinder block main body 60 side, ( It can be easily adjusted by selecting 1) the size of the maximum opening width W1sm and (2) the formation position of the first step 68A in the center line C direction. The change in the dimensions and shape of the cylinder block main body 60 shown in (1) and (2) above is extremely easy even when the cylinder block main body 60 is manufactured by casting or resin molding. Even when the cylinder block main body 60 is manufactured by casting or resin molding, which is prone to defective defects due to volume shrinkage, the cylinder block main body 60 has a larger volume capacity than a conventional cylinder block formed by casting a cylinder liner. This is because these defective defects are unlikely to occur because is very small.

The step 14 provided at a position corresponding to the second step 68B provided on the cylinder block main body 60 side can be provided at an appropriate position on the outer peripheral surface 10S with respect to the center line C direction. However, when the end face of the connecting cylinder 10 on the crank chamber 62 side in the center line C direction is set as the reference position (position 0) and the end face on the cylinder head side is set as the position L, the step 14 exceeds 0 and is 1 / 2L or less. It is preferably provided in a range, more preferably 1/6 L or more and 3/7 L or less, and further preferably 1/6 L or more and 1/3 L or less. When the step 14 is provided at a position exceeding 1 / 2L, the first step 68A provided on the cylinder block main body 60 side must be provided at a position closer to the cylinder head side. Therefore, in the direction of the center line C, the range in which the first step 68A is provided becomes narrower, and as a result, the depth D of the coolant jacket 70 is made deeper by design change in accordance with the required specifications of the internal combustion engine 100. The margin that can be made shallower is smaller.

The outer peripheral shape of the connecting cylinder 10 is basically a simple shape provided with a step 14 for dividing the outer peripheral surface 10S into the first region 10S1 and the second region 10S2, and if necessary, A groove 12 for fitting the fixing member 80 and a groove for mounting the seal member may be provided.

On the other hand, if necessary, the outer peripheral surface 10S of the connecting cylinder 10 may be provided with a protruding portion protruding from the outer peripheral surface 10S, and the outer peripheral surface 10S of the connecting cylinder 10 may be provided with a first region 10S1 and a second region. In any case of 10S2, the protruding portion may not be provided.

When the outer peripheral surface 10S is not provided with the protruding portion, there is a merit described below. That is, when a protruding portion such as a flange is provided on the outer peripheral surface 10S, the protruding portion is likely to be broken when the connecting cylinder 10 is inadvertently hit against another member during handling or storage of the connecting cylinder 10. Become. However, if the outer peripheral surface 10S is not provided with a protruding portion, such damage can be suppressed.

In addition to this, if the outer peripheral surface 10S is provided with a protruding portion, the outer peripheral surface when the connecting portion 42 of the first connecting cylinder 10A or the connecting cylinder main body 50 of the second connecting cylinder 10B is manufactured by casting. If the 10S is provided with the protruding portion, the shape of the mold becomes slightly complicated and the manufacturability is slightly lowered. When the protruding portion is provided in the first region 10S1, the size of (1) the maximum opening width W1sm of the cylinder block main body 60 and (2) the first step 68A in the center line C direction are appropriately reviewed. It becomes more difficult to redesign the capacity of the coolant jacket 70 and the formation position of the coolant jacket 70 in the center line C direction. However, such a problem can be suppressed if the protruding portion is not provided on the outer peripheral surface 10S.

On the other hand, although the above-mentioned merits are lost, the cooling control of the internal combustion engine 100 can be performed more precisely by providing the protruding portion in the first region 10S1 of the outer peripheral surface 10S. In this case, as in the first connecting cylinder 10A2 (10A, 10) illustrated in FIG. 11, in the first region 10S1, the first region 10S1 is included in the cylinder head side (Z1 direction side) region and the crank chamber side (Z1 direction side). It is preferable to provide a collar portion 16A (16) that divides the region on the Z2 direction side). Here, in the example shown in FIG. 11, the collar portion 16A is continuously formed along the outer peripheral direction, and the arrangement position of the cylinder liner 40 with respect to the center line C direction is the same at any position in the outer peripheral direction. It has a certain chain shape. The first connecting cylinder 10A2 shown in FIG. 11 is a member having the same structure as the first connecting cylinder 10A1 shown in FIG. 9, except that the flange portion 16A is provided in the first region 10S1. is there. Further, a flange portion 16A similar to that shown in FIG. 11 can also be provided in the first region 10S1 of the second connecting cylinder 10B (10) shown in FIG.

In the internal combustion engine 100 using the connecting cylinder 10 provided with the flange portion 16A for dividing the first region 10S1 into the region on the cylinder head side (Z1 direction side) and the region on the crank chamber side (Z2 direction side), the collar portion The coolant jacket 70 has a structure divided by 16A with respect to the center line C direction of the cylinder liner 40 or the cylinder bore 20. 12 and 13 are schematic cross-sectional views showing an example of an internal combustion engine 100 provided with a connecting cylinder 10 having a flange portion 16A provided in the first region 10S1. Here, in the internal combustion engine 100B (100) shown in FIG. 12, the first connecting cylinder 10A1 shown in FIG. 8 is replaced with the first connecting cylinder 10A2 having the flange portion 16A shown in FIG. It has the same structure as the internal combustion engine 100A shown in FIG. Further, the internal combustion engine 100C (100) shown in FIG. 13 replaces the first connecting cylinder 10A1 shown in FIG. 8 with the first connecting cylinder 10A2 having the flange portion 16A shown in FIG. Further, (ii) the cylinder block main body 60A shown in FIG. 8 was replaced with a cylinder block main body 60B having a structure in which a third step 68C continuous in the circumferential direction was provided on the inner peripheral surface 64S1 of the cylinder block main body 60A. Except for this, it has the same structure as the internal combustion engine 100A shown in FIG.

The third step 68C is provided at a position corresponding to the side surface of the flange portion 16A on the crank chamber side (Z2 direction side). Further, the inner peripheral surface 64S1 has a cylinder head side region 64S1A on the cylinder head side (Z1 direction side) with respect to the third step 68C and a crank chamber more than the third step 68C with the third step 68C as a boundary line. It is divided into two regions, a crank chamber side region 64S1B on the side (Z2 direction side). The crank chamber side region 64S1B is located on the inner peripheral side relative to the cylinder head side region 64S1A. In the Y direction, the cylinder head side region 64S1A shown in FIG. 13 is provided at a position flush with the inner peripheral surface 64S1 of the cylinder block main body 60A shown in FIG. However, as long as the cylinder head side region 64S1A shown in FIG. 13 is located on the outer peripheral side relative to the crank chamber side region 64S1B, the position is flush with the inner peripheral surface 64S1 of the cylinder block main body 60A shown in FIG. It does not have to be provided in.

In the internal combustion engines 100B and 100C shown in FIGS. 12 and 13, between the outer peripheral surface 10S (first region 10S1) of the first connecting cylinder 10A and the inner peripheral surface 64S1 of the hollow portion 64 of the cylinder block bodies 60A and 60B. The coolant jacket 70 formed in the above is divided into a cylinder head side portion (cylinder head side coolant jacket 70A) and a crank chamber side portion (cylinder chamber side coolant jacket 70B) by a flange portion 16A. .. Therefore, the internal combustion engines 100B and 100C shown in FIGS. 12 and 13 have a different flow rate, flow rate, and water temperature of the coolant flowing in the coolant jacket 70 than the internal combustion engine 100A shown in FIG. The jacket 70A and the crank chamber side coolant jacket 70B can be individually controlled. Therefore, in the internal combustion engines 100B and 100C, it is extremely easy to individually control the temperature of the portion of the cylinder bore 20 surrounded by the coolant jacket 70 that is closer to the cylinder head side and the portion that is closer to the crank chamber side. Is. Then, by utilizing such characteristics, for example, various merits as illustrated in the following (a) to (c) can be easily realized.

(A) Of the portion of the cylinder bore 20 surrounded by the coolant jacket 70, the temperature of the portion closer to the cylinder head side and the portion closer to the crank chamber side is controlled to control the temperature of the internal combustion engines 100B and 100C during operation. The cylindricity of the cylinder bore 20 is improved. For example, the temperature of the cylinder bore 20 in the portion closer to the cylinder head side is lower and the temperature of the cylinder bore 20 in the portion closer to the crank chamber side is higher than before the coolant jacket 70 is divided by the flange portion 16A. Can be controlled. In this case, by lowering the temperature of the cylinder bore 20 in the portion closer to the cylinder head side, it becomes easier to increase the output and advance the advance angle. Further, by raising the temperature of the cylinder bore 20 in the portion closer to the crank chamber side, it becomes easy to reduce the friction and improve the warmth. In addition to this, the cylindricity of the cylinder bore 20 is also improved, which makes it easy to reduce the amount of blow-by gas and the amount of lubricating oil consumed.
(B) Of the portion of the cylinder bore 20 surrounded by the coolant jacket 70, the portion closer to the cylinder head side is relatively improved in cooling efficiency with respect to the portion closer to the crank chamber side, so that the portion is closer to the cylinder head side. The temperature of the inner wall surface (sliding surface) of the cylinder bore 20 is lowered to improve knock resistance and improve fuel efficiency.
(C) The flow velocity, flow rate, and water temperature of the coolant of the cylinder head side coolant jacket 70A and the crank chamber side coolant so that the optimum output, fuel efficiency, etc. can be obtained according to the operating conditions of the internal combustion engines 100B and 100C. The flow velocity, flow rate, and water temperature of the coolant of the jacket 70B are set individually.

In the internal combustion engine 100B shown in FIG. 12, the top surface of the flange portion 16A is in contact with the inner peripheral surface 64S1 of the cylinder block main body 60A. Further, in the internal combustion engine 100C shown in FIG. 13, the top surface of the flange portion 16A comes into contact with the cylinder head side region 64S1A of the inner peripheral surface 64S1 of the cylinder block main body 60A, and the flange portion 16A is on the crank chamber side (Z2 direction side). The portion of the side surface on the top surface side is in contact with the stepped surface portion of the third step 68C. In this case, it is preferable to provide a sealing member such as an O-ring at the interface between the top surface of the flange portion 16A and the inner peripheral surface 64S1 to completely seal the interface between the flange portion 16A and the inner peripheral surface 64S1. The O-ring is used, for example, by providing a groove along the circumferential direction of the top surface of the flange portion 16A and mounting the O-ring in the groove, or in the case of the internal combustion engine 100C shown in FIG. 13, the step surface of the third step 68C. A groove is provided along the circumferential direction of the portion, and the groove can be used by mounting the groove.

Further, as long as the controllability when individually controlling the flow velocity, flow rate, and water temperature of the coolant between the cylinder head side coolant jacket 70A and the crank chamber side coolant jacket 70B is not significantly impaired, the seal is sealed. The member may be omitted, or a slight gap may be formed between the top surface of the flange portion 16A and the inner peripheral surface 64S1. Further, a flow path is provided in a part of the flange portion 16A in the circumferential direction so as to penetrate in the center line C direction and connect the cylinder head side coolant jacket 70A and the crank chamber side coolant jacket 70B, if necessary. May be good.

If the flange portion 16A can divide the coolant jacket 70 into a cylinder head side coolant jacket 70A and a crank chamber side coolant jacket 70B, the first region 10S1 is arbitrary with respect to the center line C direction. Can be provided at the position of. However, when the end of the first region 10S1 in the center line C direction on the cylinder head side is set to the reference position 0 and the total length of the first region 10S1 in the center line C direction is L1, the collar portion 16A is 0.2 × L1. It is preferable to provide it within the range of about 0.5 × L1. Similarly, when the end of the connecting cylinder 10 in the center line C direction on the cylinder head side is set to the reference position 0 and the total length of the connecting cylinder 10 in the center line C direction is L, the flange portion 16A is 0.14 × L to. It is preferable to provide it within the range of about 0.37 × L.

Further, the flange portion 16 provided on the outer peripheral surface 10S may be continuously formed along the center line C direction of the cylinder liner 40 or the cylinder bore 20. FIG. 15 is a schematic cross-sectional view showing another modification of the first connecting cylinder shown in FIG. In the first connecting cylinder 10A3 (10A, 10) shown in FIG. 15, the flange portion 16B (16) is continuously formed along the center line C direction on the outer peripheral surfaces 10S on both end sides of the cylinder bore 20 in the alignment direction. Is provided. In the internal combustion engine 100 using the first connecting cylinder 10A3 shown in FIG. 15, the coolant jacket 70 is on one side (Y1 side) of the plane (ZX plane) including the center line C of each cylinder liner 40 or cylinder bore 20. And the other side (Y2 side). In the example shown in FIG. 15, the flange portion 16B is provided on the outer peripheral surfaces 10S on both ends in the arrangement direction of the cylinder bores 20, but may be provided at other positions.

In the example shown in FIG. 15, the collar portion 16B is provided in both the first region 10S1 and the second region 10S2 of the outer peripheral surface 10S. Therefore, of the inner peripheral surfaces 64S of the hollow portion 64 of the cylinder block main body 60 used in combination with the first connecting cylinder 10A3 shown in FIG. 15, at least the inner peripheral surfaces 64S2 and 64S3 have guide grooves corresponding to the flange portions 16B. Is provided. Further, depending on the height of the flange portion 16B, a guide groove corresponding to the flange portion 16B may be provided on the inner peripheral surface 64S1 in addition to the inner peripheral surfaces 64S2 and 64S3. That is, in the cylinder block main body 60, at least a part or all of the inner peripheral surfaces 64S on both ends in the longitudinal direction (X direction) of the opening of the hollow portion 64 are provided with guide grooves corresponding to the flange portion 16B. Is continuously formed from one end side (Z2 side) to the other end side (Z1 side). Therefore, in the first connecting cylinder 10A3, the flange portion 16B is fitted with the guide groove, so that the first connecting cylinder 10A3 is stably fixed by the cylinder block main body 60 having the guide groove on the inner peripheral surface 64S. Will be done.

In the example shown in FIG. 15, on the outer peripheral surface 10S, the flange portion 16B is continuously provided from one end side (Z2 side) to the other end side (Z1 side) of the first connecting cylinder 10A3. However, when the flange portion 16B is provided for the main purpose of fixing the first connecting cylinder 10A3 to the cylinder block main body 60 more stably, among the inner peripheral surfaces 64S of the hollow portion 64, the inner peripheral surface 64S2, On the outer peripheral surface 10S, the flange portion 16B should be provided only from the position closer to the other end side (Z1 side) than the step 14 to the one end side (Z2 side) so as to correspond to the guide groove provided in 64S3. Just do it. FIG. 16 shows a first connecting cylinder 10A4 (10A, 10) in which the flange portion 16B is provided on the outer peripheral surface 10S as described above.

Further, when the flange portion 16B is provided mainly for the purpose of dividing the coolant jacket 70, the collar portion 16B is on the other end side (Z1 side) on the outer peripheral surface 10S so as to correspond to the inner peripheral surface 64S1 of the hollow portion 64. It suffices to be provided only up to a position closer to the other end side (Z1 side) than the step 14. FIG. 17 shows a first connecting cylinder 10A5 (10A, 10) in which the flange portion 16B is provided on the outer peripheral surface 10S as described above.

A first connecting cylinder 10A3, 10A4, 10A5 in which a flange portion 16B continuously formed along the center line C direction of the cylinder liner 40 or the cylinder bore 20 is provided on the outer peripheral surface 10S, and a cylinder block main body 60 are used. The assembled internal combustion engine 100 can be applied to all types of engines such as in-line engines, V-type engines, and horizontally opposed engines.

However, it is particularly preferable that the internal combustion engine 100 using the first connecting cylinder 10A3 illustrated in FIG. 15 or the first connecting cylinder 10A4 illustrated in FIG. 16 is a horizontally opposed engine. In this case, even if gravity acts on the first connecting cylinder 10A4 from a direction substantially orthogonal to the center line C of the cylinder bore 20 in the horizontally opposed engine, the first connecting cylinder 10A4 is tilted with respect to the horizontal plane. It can be surely suppressed. Therefore, even when assembling the internal combustion engine 100 in a state where the cylinder block main body 60 provided with the guide groove on the inner peripheral surface 64S is placed horizontally (the Z direction substantially coincides with the horizontal direction), the cylinder block main body 60 is also used. The positioning of the first connecting cylinder 10A4 with respect to the above is easy.

FIG. 18 shows an example of a cylinder block main body used in combination with the first connecting cylinder 10A3 shown in FIG. The cylinder block main body 60C (60) shown in FIG. 18 is a modification of the cylinder block main body 60A shown in FIG. 6, and is different from the cylinder block main body 60A except that a guide groove 69 is further provided for the cylinder block main body 60A. It is a member having a similar size and shape. As shown in FIG. 18, the guide groove 69 is provided on the inner peripheral surface 64S on both end sides of the opening 64X of the hollow portion 64 in the longitudinal direction (X direction). Here, the guide groove 69 is provided on any of the inner peripheral surface 64S1, the inner peripheral surface 64S2, and the inner peripheral surface 64S3 so as to correspond to the flange portion 16B shown in FIG. However, the guide groove 69 may be omitted on the inner peripheral surface 64S1 depending on the height of the flange portion 16B. Further, even when the first connecting cylinder 10A4 shown in FIG. 16 is used, it is not necessary to provide the guide groove 69 on the inner peripheral surface 64S1.

Further, the shape and formation position of the collar portion 16 are not limited to the examples shown in FIGS. 11 to 13 and 15 to 17. For example, the collar portion 16 is formed in a direction parallel to the flange portion 16A formed continuously in the outer peripheral direction as illustrated in FIGS. 11 to 13 and the center line C as illustrated in FIGS. 15 to 17. It may be a combination with the collar portion 16B formed continuously.

For example, it is assumed that the first region 10S1 of the connecting cylinder 10 is divided into two with a plane (XZ plane) including the center line C of each cylinder liner 40 or each cylinder bore 20 as a dividing boundary surface. In this case, in the first region 10S1 on one side (Y1 direction side) divided into two, a continuous semi-linked ring-shaped flange portion 16A so as to be parallel to the outer peripheral direction is located at a position relatively closer to the crank chamber side. In the first region 10S1 on the other side (Y2 direction side) divided into two, a continuous semi-linked ring-shaped collar portion 16A so as to be parallel to the outer peripheral direction is relatively closer to the cylinder head side. Can be formed in position. Then, both end portions of one half-linked ring-shaped flange portion 16A and both end portions of the other half-linked ring-shaped flange portion 16A are flange portions 16B whose respective ends are continuous in a direction parallel to the center line C. Connected by. If such a configuration is adopted, the ratio of the depth of the cylinder head side coolant jacket 70A to the depth of the crank chamber side coolant jacket 70B is different between one side and the other side of the split boundary surface. Can be done. Such a structure is effective, for example, when it is desired to perform asymmetric cooling control between one side and the other side of the divided boundary surface.

Further, the flange portion 16 includes a first portion (flange portion 16A) that divides the first region 10S1 into a region on the cylinder head side (Z1 direction side) and a region on the crank chamber side (Z2 direction side), and a first region 10S1. Of these, a second portion (flange portion 16B) that divides a portion forming the side wall surface of the coolant jacket 70 with respect to the outer peripheral direction may be provided. In the internal combustion engine 100 provided with the connecting cylinder 10 having such a flange portion 16, the coolant jacket 70 can be divided by the first portion with respect to the center line C direction of the cylinder liner 40 or the cylinder bore 20. In addition to this, the second portion also allows the coolant jacket 70 to be split or split with respect to the outer peripheral direction. Therefore, it becomes easy to perform more precise cooling control not only in the center line C direction but also in the outer peripheral direction.

As a specific example, a first portion (flange portion 16A) that is continuously formed along the outer peripheral direction and has a chained shape in which the arrangement position with respect to the center line C direction is the same at any position in the outer peripheral direction. A connecting cylinder 10 having a collar portion 16 having two linear second portions (flange portions 16B) provided along a portion where the divided boundary surface and the first region 10S1 intersect, and a connecting cylinder 10 provided in the first region 10S1. An internal combustion engine 100 using this can be exemplified. In this case, the coolant jacket 70 is divided into a cylinder head side coolant jacket 70A and a crank chamber side coolant jacket 70B by the first portion. Further, the cylinder head side coolant jacket 70A is further divided into one side (Y1 direction side) portion and the other side (Y2 direction side) portion of the division boundary surface by the second portion, and the crank chamber side. The coolant jacket 70B is also divided into a portion on one side (Y1 direction side) and a portion on the other side (Y2 direction side) of the division boundary surface. That is, the coolant jacket 70 is divided into four parts.

The internal combustion engine 100 having a structure in which the connecting cylinder 10 is fixed to the cylinder block main body 60 by fitting the flange portion and the guide groove as described with reference to FIGS. 15, 16 and 18. , At least a combination of a connecting cylinder 10 having the structure shown in (1) or (2) below and a cylinder block main body 60 may be used.
(1) A connecting cylinder 10 having a flange portion 16B (fixing flange portion) provided on the outer peripheral surface 10S along a direction parallel to the center line C of each cylinder bore 20 provided in the connecting cylinder 10, and a hollow portion. An internal combustion engine 100 having a cylinder block main body 60 provided with a guide groove 69 for fitting a collar portion 16B (fixing collar portion) on the inner peripheral surface 64S of 64.
(2) A cylinder block main body 60 provided with a flange portion (fixing flange portion) on the inner peripheral surface 64S of the hollow portion 64 along a direction parallel to the penetrating direction (Z direction) of the hollow portion 64, and a connecting cylinder. An internal combustion engine 100 having a connecting cylinder 10 provided on an outer peripheral surface 10S of 10 with a guide groove (provided in the cylinder block main body 60) to be fitted with a flange portion (fixing flange portion).

Here, the internal combustion engine 100 shown in (1) and (2) above preferably has the structure shown below.

That is, in the internal combustion engine 100 shown in (1) above, the collar portion 16B (fixing collar portion) is a connecting cylinder 10 on both ends in the arrangement direction (X direction) of each cylinder bore 20 provided in the connecting cylinder 10. Guide grooves 69 are provided on the inner peripheral surface 64S of the hollow portion 64 of the cylinder block main body 60 at both ends in the longitudinal direction (X direction) of the opening 64X of the hollow portion 64. Is preferable. Further, in the internal combustion engine 100 shown in (2) above, the flange portion (fixing flange portion) is the hollow portion 64 of the cylinder block main body 60 at both ends of the opening 64X of the hollow portion 64 in the longitudinal direction (X direction). It is preferable that the guide grooves are provided on the outer peripheral surface 10S of the connecting cylinder 10 at both ends in the arrangement direction (X direction) of the respective cylinder bores 20 provided on the connecting cylinder 10. ..

The structure in which the fixing flange portion and the guide groove are fitted on both ends in the X direction as described above is particularly suitable when the internal combustion engine 100 is a horizontally opposed engine. In this case, the inclination of the connecting cylinder 10 in the internal combustion engine 100 can be suppressed, and the positioning of the connecting cylinder 10 with respect to the cylinder block main body 60 at the time of assembly can be facilitated.

In the internal combustion engine 100 shown in (1) and (2) above, the coolant jacket can be provided at any of the positions shown in (i) to (iii) below, but is provided at the position shown in (ii). Is particularly preferred. When the coolant jacket 70 forming a large space is provided between the outer peripheral surface 10S of the connecting cylinder 10 and the inner peripheral surface 64S of the hollow portion 64 of the cylinder block main body 60, the connecting cylinder 10 in the internal combustion engine 100 The support / fixation tends to be unstable as compared with the case where the coolant jacket is provided at the position shown in (i) or (iii). However, the internal combustion engine 100 shown in (1) and (2) above, which has a structure in which the fixing flange portion and the guide groove are fitted, can suppress the above-mentioned problem.
(I) Inside the connecting cylinder 10 (inside the outer peripheral surface 10S of the connecting cylinder 10)
(Ii) Between the outer peripheral surface 10S of the connecting cylinder 10 and the inner peripheral surface 64S of the hollow portion 64 of the cylinder block main body 60 (iii) Inside the cylinder block main body 60 (outer peripheral side of the inner peripheral surface 64S of the hollow portion 64)

Further, in the internal combustion engine 100 having the coolant jacket 70 at the position shown in (ii), the collar portion (split collar portion) for dividing the coolant jacket 70 into two or more portions is formed in (a) the connecting cylinder 10. It may be provided on at least one of the outer peripheral surface 10S and (b) the inner peripheral surface 64S of the hollow portion 64 of the cylinder block main body 60.

Here, as a specific example of (a) providing the split collar portion on the outer peripheral surface 10S of the connecting cylinder 10, the internal combustion engine 100B shown in FIG. 12, the internal combustion engine 100C shown in FIG. 13, and the first connection shown in FIG. An internal combustion engine 100 in which the cylinder 10A3 and the cylinder block main body 60C shown in FIG. 18 are combined can be mentioned. In the internal combustion engine 100B shown in FIG. 12 and the internal combustion engine 100C shown in FIG. 13, the coolant jacket 70 is divided into two parts (cylinder head side coolant jacket 70A and crank chamber side coolant) by the flange portion 16A (dividing collar portion). It is divided into a jacket 70B).

Further, in the internal combustion engine 100 in which the first connecting cylinder 10A3 shown in FIG. 15 and the cylinder block main body 60C shown in FIG. 18 are combined, the coolant jacket 70 is provided with two parts (split collar portion) by the flange portion 16B (splitting flange portion). It is divided into a portion on one side (Y1 side) and a portion on the other side (Y2 side) with respect to a plane including a plurality of center lines C. The collar portion 16B in the internal combustion engine 100 in which the first connecting cylinder 10A3 shown in FIG. 15 and the cylinder block main body 60C shown in FIG. 18 are combined is used as a fixing collar portion, but the split collar portion is used. It also has the function of. As described above, the fixing collar portion may also have the function of the dividing collar portion.

On the other hand, (b) specific examples in which the split collar portion is provided on the inner peripheral surface 64S of the hollow portion 64 of the cylinder block main body 60 include the internal combustion engines 100B and 100C shown in FIGS. 12 and 13 and the thirteenth shown in FIG. In an internal combustion engine 100 in which one connecting cylinder 10A3 and a cylinder block main body 60C shown in FIG. 18 are combined, an internal combustion engine in which a flange portion (dividing collar portion) is provided not on the connecting cylinder 10 side but on the cylinder block main body 60 side. 100 is mentioned.

Further, in the first connecting cylinders 10A2, 10A3, 10A4, and 10A5 illustrated in FIGS. 11 to 13 and 15 to 17, the collar portion 16 is integrally formed with the main body portion of the first connecting cylinder 10A2 by casting. A connecting cylinder 10 that is formed but does not have a flange portion 16 as illustrated in FIGS. 9 and 10 has (1) a member having a shape corresponding to the annular flange portion 16A, and (2) a center line. A member having a shape corresponding to a linear flange portion 16B extending in a direction parallel to C, or (3) a second portion linear with the above-mentioned semi-annular or annular first portion (flange portion 16A). The collar portion 16 may be provided by mounting and fixing a member having a shape corresponding to the collar portion 16 having the portion (flange portion 16B).

The fitting method of the fitting portion in which the flange portion 16 and the cylinder block main body 60 are fitted is not particularly limited, and any fitting method selected from crevice fit, intermediate fit and tight fit may be used. However, when it is desired to suppress the deformation of the cylinder bore 20, a clearance fit or an intermediate fit is preferable, and a clearance fit is more preferable.

Further, the flange portion (dividing collar portion) provided on the connecting cylinder 10 side or the cylinder block main body 60 side for the purpose of dividing the coolant jacket 70 into two or more portions is a through hole penetrating in the width direction of the flange portion. It is preferable not to have. For example, the collar portion 16A is continuously formed along the outer peripheral direction of the connecting cylinder 10, or is continuously formed along the inner peripheral direction of the hollow portion 64 of the cylinder block body 60 instead of the collar portion 16A. If the flange portion does not have a through hole, the cylinder head side coolant jacket 70A and the crank chamber side coolant jacket 70B do not communicate with each other through the through hole. Therefore, the cylinder head side coolant jacket 70A and the crank chamber side coolant jacket 70B can more reliably control the liquid temperature, flow rate, and the like of the coolant separately and independently. The "width direction of the collar portion" means a direction parallel to the surface on which the collar portion is provided and orthogonal to the longitudinal direction of the collar portion, and in the collar portion 16A shown in FIG. 11, Z It means the length in the direction, and in the flange portion 16B shown in FIG. 15, it means the length in the outer peripheral direction (or the Y direction).

Further, when the collar portion (dividing collar portion) has a through hole penetrating in the width direction of the collar portion, the collar portion is, in addition to the through hole, a closing member such as a stopper or a lid capable of closing the through hole. It is preferable to have. In this case, it is preferable that the through hole is closed by a closing member such as a plug or a lid when the internal combustion engine 100 is in operation. For example, when the flange portion 16A has a through hole in a state where the flange portion 16A is not blocked during the operation of the internal combustion engine 100B illustrated in FIG. 12, the coolant is cooled through the through hole on the cylinder head side. Since it is possible to move back and forth between the jacket 70A and the crank chamber side coolant jacket 70B, it becomes difficult to perform more precise cooling control. These points are the same when the flange portion 16 is provided on the inner peripheral surface 64S1 of the cylinder block main body 60. The through hole may be opened for the purpose of maintenance / repair of the internal combustion engine 100, for example, when the internal combustion engine 100 is not in operation.

In a conventional internal combustion engine having a structure in which a plurality of cylinder liners are cast and wrapped in a cylinder block, a portion excluding the cylinder liner is integrally formed by casting. Therefore, in the conventional internal combustion engine, the coolant jacket 70 is divided into a cylinder head side coolant jacket 70A and a crank chamber side coolant jacket 70B as shown in the internal combustion engines 100B and 100C shown in FIGS. 12 and 13. It was impossible to realize the structure (coolant jacket split structure) by the casting process alone. Further, in order to realize the coolant jacket split structure after casting, it is necessary to construct the coolant jacket split structure in the coolant jacket having a narrow and deep opening on the cylinder head side. , Manufacturability is extremely poor, and mass production is impossible. However, in the case of the internal combustion engine 100 of the present embodiment using the connecting cylinder 10 having the flange portion 16, the coolant jacket split structure is manufactured by casting the connecting cylinder 10 having the flange portion 16 manufactured by casting. It can be realized extremely easily by combining with the cylinder block main body 60, and the mass productivity is also extremely excellent.

The internal combustion engine 100 of the present embodiment may have at least one fitting portion into which the connecting cylinder 10 and the cylinder block main body 60 are fitted. The fitting portion in this case is a portion (fitting portion 64J) on one end side of the hollow portion 64 of the cylinder block main body 60. However, as illustrated in FIGS. 8, 12 and 13, the internal combustion engine 100 of the present embodiment has other than the first fitting portion (fitting portion 64J) located closest to one end side (Z2 side). , The second fitting portion located closest to the other end side (Z1 side) (such as the fitting portion via the fixing member 80 illustrated in FIGS. 8, 12 and 13) and one end side (Z2) in the Z direction. Like a third fitting portion (such as a fitting portion between the flange portion 16 illustrated in FIGS. 12 and 13 and the cylinder block main body 60) located between the other end side (Z1 side). In some cases, it may have two or more fitting portions in the Z direction.

As described above, when the internal combustion engine 100 of the present embodiment has two or more fitting portions in the Z direction, the fitting method in each fitting portion may be the same or different. In addition, examples of a combination of suitable fitting methods for each fitting portion include the following embodiments.

(When the internal combustion engine 100 has first, second and third fitting portions)
・ Combination example A1
First fitting portion to third fitting portion: Clearance fit In this combination, it is extremely easy to suppress the deformation of the cylinder bore 20 in the entire Z direction.
・ Combination example A2
First fitting part: intermediate fitting part, second fitting part and third fitting part: clearance fit This combination makes it extremely easy to suppress deformation of the cylinder bore 20 in the vicinity of the region where the piston reciprocates. The connecting cylinder 10 can be more stably fixed to the cylinder block main body 60 as compared with the combination example A1.

(When the internal combustion engine 100 has first and third fitting portions)
・ Combination example B1
First fitting portion and third fitting portion: Clearance fit In this combination, it is extremely easy to suppress the deformation of the cylinder bore 20 in the entire Z direction.
・ Combination example B2
First fitting part: intermediate fitting, third fitting part: clearance fitting In this combination, it is extremely easy to suppress the deformation of the cylinder bore 20 in the vicinity of the region where the piston reciprocates, while compared with the combination example B1. The connecting cylinder 10 can be more stably fixed to the cylinder block main body 60.

(When the internal combustion engine 100 has the first and second fitting portions)
・ Combination example C1
First fitting portion and second fitting portion: Clearance fit In this combination, it is extremely easy to suppress the deformation of the cylinder bore 20 in the entire Z direction.
・ Combination example C2
First fitting part: intermediate fit, second fitting part: clearance fit In this combination, it is extremely easy to suppress the deformation of the cylinder bore 20 in the vicinity of the region where the piston reciprocates, while compared with the combination example C1. The connecting cylinder 10 can be more stably fixed to the cylinder block main body 60.

The internal combustion engine 100 of the present embodiment is used as a liquid-cooled gasoline engine, a liquid-cooled diesel engine, a liquid-cooled engine using fuel (alcohol, natural gas, hydrogen gas, etc.) other than gasoline or light oil. it can. The use of the internal combustion engine 100 of the present embodiment is not particularly limited, and can be used for various purposes such as for vehicles such as automobiles, motorcycles, and railroad vehicles, for ships, for aircraft, and for power generation. is there. The displacement of the internal combustion engine 100 of the present embodiment is not particularly limited and can be appropriately selected depending on the application, but is generally selected in the range of 20 cc to 60 L according to the application. For automobile applications including large vehicles such as large trucks and buses, for example, it is preferable to select in the range of 50 cc to 30 L, and for automobile applications excluding large vehicles such as large trucks and buses. For example, it is preferable to select in the range of 50 cc to 7 L, and more preferably to select in the range of 300 cc to 4 L. For motorcycles, it is preferably selected in the range of 20 cc to 1.5 L, and more preferably selected in the range of 50 cc to 1.2 L.

The internal combustion engine 100 of the present embodiment is also applicable to a large engine (for example, a large diesel engine for ships and / or a large engine having a displacement of more than 30 L or 60 L), but exhaust. It becomes difficult to manufacture the connecting cylinder 10 and the cylinder block main body 60 (particularly, the cylinder block main body 60) corresponding to the displacement or the size of the engine. Therefore, the displacement of the internal combustion engine 100 of the present embodiment is preferably 60 L or less, preferably 30 L or less, and particularly preferably 10 L or less. Further, for the same reason, the internal combustion engine 100 of the present embodiment is preferably an internal combustion engine excluding the large engine as described above.

Further, the connecting cylinder 10 of the present embodiment may be combined with a member other than the cylinder block main body 60 to form an internal combustion engine. The structure of such an internal combustion engine is not particularly limited, and either a liquid-cooled type or an air-cooled type may be used. For example, in the case of a large diesel engine for ships and / or a large engine having a displacement of more than 30 L or 60 L, a cover that surrounds the connecting cylinder 10 and the outer peripheral surface 10S of the connecting cylinder 10 near the cylinder head. It can be an internal combustion engine having a member. This cover member is fixed to the connecting cylinder 10 by a plurality of bolts. In this case, the cooling liquid is supplied to the cooling chamber formed between the outer peripheral surface 10S of the connecting cylinder 10 and the cover member. In such a large displacement internal combustion engine, even if an attempt is made to manufacture a cylinder block main body 60 having a large size and volume according to the displacement by casting, it is difficult to manufacture due to problems such as cavities, but if it is a cover member, the cylinder It is easy to manufacture because its size and volume are much smaller than the block body 60.

10: Connecting cylinder 10A, 10A1, 10A2, 10A3, 10A4, 10A5: First connecting cylinder 10B: Second connecting cylinder 10S: Outer peripheral surface 10S1: First region (part of outer peripheral surface 10S)
10S2: Second region (a part of the outer peripheral surface 10S)
10ES: End face 12: Groove 14: Step 16, 16A, 16B: Brim portion 20: Cylinder bore 20B: Inner peripheral surface 30, 30A, 30B, 30C: Coolant passage 34: Opening 36: End face 40: Cylinder liner 40A: Outer peripheral surface 40B: Inner peripheral surface 42: Connecting portion 50: Connecting cylinder main body 50B: Inner peripheral surface 52: Coating 52A: Outer peripheral side surface 52B: Surface 60, 60A, 60B, 60C: Cylinder block main body 62: Crank chamber 64: Hollow Part 64J: Fitting part 64X: Opening 64S, 64S1, 64S2, 64S3: Inner peripheral surface 64S1A: Cylinder head side region (part of inner peripheral surface 64S1)
64S1B: Crank chamber side region (part of inner peripheral surface 64S1)
66: Groove 68A: First step 68B: Second step 68C: Third step 69: Guide groove 70: Coolant jacket 70A: Cylinder head side coolant jacket 70B: Cylinder chamber side coolant jacket 80: (Head Side) Fixing members 100, 100A, 100B, 100C: Internal combustion engine

The coolant passage 30 having such a slit-shaped cross-sectional shape is (a) for a coolant having an opening 34 continuous in the Y direction on the end surface 36 on the other end side (Z1 side) of the connecting cylinder 10. Passage 30B (30) (FIG. 14 (B)) or (b) Inside (one end side (Z2 side)) of the other end side (Z1 side, side on which the cylinder head is arranged) of the connecting cylinder 10 30C (30) (FIG. 14C) for the coolant provided in the above can also be mentioned. However, the coolant passage 30C having a slit-shaped cross-sectional shape as illustrated in FIG. 14C is inside (one end side (Z2)) of the end surface 36 on the other end side (Z1 side) of the ( b ) connecting cylinder 10. By providing it on the side)), it is possible to increase the degree of freedom in cooling design around the cylinder bore 20. When forming the coolant passage 30C having a slit-shaped cross-sectional shape as illustrated in FIG. 14C, it is preferable to carry out the coolant passage forming step at least before the fitting step. This is because, with such a process sequence, the degree of freedom in selecting the processing means and processing method required to form the coolant passage 30C is extremely high.

(A) Of the portion of the cylinder bore 20 surrounded by the coolant jacket 70, the temperature of the portion closer to the cylinder head side and the portion closer to the crank chamber side is controlled to control the temperature of the internal combustion engines 100B and 100C during operation. The cylindricity of the cylinder bore 20 is improved. For example, the temperature of the cylinder bore 20 in the portion closer to the cylinder head side is lower and the temperature of the cylinder bore 20 in the portion closer to the crank chamber side is higher than before the coolant jacket 70 is divided by the flange portion 16A. Can be controlled. In this case, by lowering the temperature of the cylinder bore 20 in the portion closer to the cylinder head side, it becomes easier to increase the output and advance the advance angle. Further, it is easy to decrease and increase the warm-up of friction by a higher temperature of the cylinder bore 20 of the portion of the crank chamber side toward. In addition to this, the cylindricity of the cylinder bore 20 is also improved, which makes it easy to reduce the amount of blow-by gas and the amount of lubricating oil consumed.
(B) Of the portion of the cylinder bore 20 surrounded by the coolant jacket 70, the portion closer to the cylinder head side is relatively improved in cooling efficiency with respect to the portion closer to the crank chamber side, so that the portion is closer to the cylinder head side. The temperature of the inner wall surface (sliding surface) of the cylinder bore 20 is lowered to improve knock resistance and improve fuel efficiency.
(C) The flow velocity, flow rate, and water temperature of the coolant of the cylinder head side coolant jacket 70A and the crank chamber side coolant so that the optimum output, fuel efficiency, etc. can be obtained according to the operating conditions of the internal combustion engines 100B and 100C. The flow velocity, flow rate, and water temperature of the coolant of the jacket 70B are set individually.

However, it is particularly preferable that the internal combustion engine 100 using the first connecting cylinder 10A3 illustrated in FIG. 15 or the first connecting cylinder 10A4 illustrated in FIG. 16 is a horizontally opposed engine. In this case, in a horizontal opposed type engine, also act gravity from a direction centerline C substantially perpendicular to the first connecting cylinder 10A3, cylinder bore 20 relative to 10A4, the first connecting cylinder 10A3, 10A4 horizontal plane It is possible to surely suppress the inclination with respect to. Therefore, even when assembling the internal combustion engine 100 in a state where the cylinder block main body 60 provided with the guide groove on the inner peripheral surface 64S is placed horizontally (the Z direction substantially coincides with the horizontal direction), the cylinder block main body 60 is also used. The positioning of the first connecting cylinders 10A3 and 10A4 with respect to the above is easy.

Further, in the first connecting cylinders 10A2 , 10A3, 10A4 , and 10A5 illustrated in FIGS. 11 to 13 and 15 to 17, the collar portion 16 is formed by casting the first connecting cylinders 10A2 , 10A3, 10A4 , and 10A5 . A member having a shape corresponding to (1) an annular flange portion 16A in a connecting cylinder 10 which is integrally formed with the main body portion but does not have a flange portion 16 as illustrated in FIGS. 9 and 10. , (2) A member having a shape corresponding to a linear collar portion 16B extending along a direction parallel to the center line C, or (3) the first part of the semi-continuous ring or the continuous ring (flange portion 16A) described above. The collar portion 16 may be provided by mounting and fixing a member having a shape corresponding to the collar portion 16 having a linear second portion (flange portion 16B).

10: Connecting cylinder 10A, 10A1, 10A2, 10A3, 10A4, 10A5: First connecting cylinder 10B: Second connecting cylinder 10S: Outer peripheral surface 10S1: First region (part of outer peripheral surface 10S)
10S2: Second region (a part of the outer peripheral surface 10S )
12 : Groove 14: Step 16, 16A, 16B: Flange 20: Cylinder bore 20B: Inner peripheral surface 30, 30A, 30B, 30C: Coolant passage 34: Opening 36: End face 40: Cylinder liner 40A: Outer peripheral surface 40B: Inner peripheral surface 42: Connecting portion 50: Connecting cylinder main body 50B: Inner peripheral surface 52: Coating 52A: Outer peripheral side surface 52B: Surface 60, 60A, 60B, 60C: Cylinder block main body 62: Crank chamber 64: Hollow portion 64J : Fitting portion 64X: Openings 64S, 64S1, 64S2, 64S3: Inner peripheral surface 64S1A: Cylinder head side region (part of inner peripheral surface 64S1)
64S1B: Crank chamber side region (part of inner peripheral surface 64S1)
66: Groove 68A: First step 68B: Second step 68C: Third step 69: Guide groove 70: Coolant jacket 70A: Cylinder head side coolant jacket 70B: Cylinder chamber side coolant jacket 80: ( Cylinder) Head side) Fixing members 100, 100A, 100B, 100C: Internal combustion engine

Claims (35)

(1) A first connecting cylinder including two or more cylinder liners and a connecting portion for connecting the two or more cylinder liners to each other, and
(2) A second connecting cylinder including a connecting cylinder main body provided with two or more cylinder bores and a coating covering the inner peripheral surface of the connecting cylinder main body provided with the cylinder bores.
A crank chamber is formed on one end side, a cylinder head is assembled on the other end side, and a hollow portion penetrating from the one end side to the other end side is provided for any of the connecting cylinders selected from the group consisting of. A method for manufacturing an internal combustion engine, which comprises manufacturing an internal combustion engine at least through a fitting step of fitting the cylinder block body into the hollow portion. The method for manufacturing an internal combustion engine according to claim 1, wherein the fitting step is performed by any fitting method selected from a clearance fit, an intermediate fit, and a tight fit. The connecting cylinder is the first connecting cylinder,
The internal combustion engine according to claim 1 or 2, wherein the sliding surface forming step of forming the sliding surface by finishing the inner peripheral surface of the cylinder liner is performed only before the fitting step. Manufacturing method of the engine. The connecting cylinder is the first connecting cylinder,
After performing a film forming step of forming a film on the inner peripheral surface of the cylinder liner, a sliding surface forming step of forming a sliding surface by finishing the surface of the film is performed.
The method for manufacturing an internal combustion engine according to any one of claims 1 to 3, wherein the sliding surface forming step is performed only before the fitting step. The connecting cylinder is the second connecting cylinder,
The sliding surface forming step of forming the sliding surface by finishing the surface of the coating film covering the inner peripheral surface of the connecting cylinder body portion provided with the cylinder bore is performed only before the fitting step. The method for manufacturing an internal combustion engine according to claim 1 or 2. The method for manufacturing an internal combustion engine according to any one of claims 3 to 5, wherein the fitting step is performed by any fitting method selected from a clearance fit and an intermediate fit. .. The method for manufacturing an internal combustion engine according to any one of claims 3 to 5, wherein the fitting step is performed by a clearance fit. The sliding surface forming step is characterized in that the connecting cylinder is assembled to a jig simulating the cylinder block main body and the cylinder head, and at least the connecting cylinder is heated. The method for manufacturing an internal combustion engine according to any one of claims 3 to 7. Any of claims 1 to 8, wherein the cooling liquid passage forming step of forming the cooling liquid passage between two cylinder bores adjacent to each other of the connecting cylinder is performed at least before the fitting step. The method for manufacturing an internal combustion engine according to one. The coolant passage is provided inside the end surface of the connecting cylinder on the side where the cylinder head is arranged, and is also provided.
The method for manufacturing an internal combustion engine according to claim 9, wherein the cross-sectional shape of the coolant passage in a plane parallel to the center line of each cylinder bore provided in the connecting cylinder is a slit shape. (1) A first connecting cylinder including two or more cylinder liners and a connecting portion for connecting the two or more cylinder liners to each other, and
(2) A second connecting cylinder including a connecting cylinder main body provided with two or more cylinder bores and a coating covering the inner peripheral surface of the connecting cylinder main body provided with the cylinder bores.
With any connecting cylinder selected from the group consisting of
A cylinder block main body having a crank chamber formed on one end side, a cylinder head assembled on the other end side, and a hollow portion provided with a hollow portion penetrating from the one end side to the other end side is provided at least.
An internal combustion engine characterized in that the connecting cylinder is detachably fitted into the hollow portion of the cylinder block main body. The internal combustion engine according to claim 11, wherein the connecting cylinder is fitted into the hollow portion of the cylinder block main body by any fitting method selected from a clearance fit and an intermediate fit. .. A coolant passage is provided between two cylinder bores of the connecting cylinders adjacent to each other, inside the end face of the connecting cylinder on the side where the cylinder head is arranged, and at the same time.
The internal combustion engine according to claim 11 or 12, wherein the cross-sectional shape of the coolant passage in a plane parallel to the center line of each cylinder bore provided in the connecting cylinder is a slit shape. A fixing collar is provided on the outer peripheral surface of the connecting cylinder along a direction parallel to the center line of each cylinder bore provided in the connecting cylinder.
The internal combustion engine according to any one of claims 11 to 13, wherein a guide groove for fitting with the fixing collar portion is provided on the inner peripheral surface of the hollow portion of the cylinder block main body. .. The fixing collars are provided on the outer peripheral surfaces of the connecting cylinders on both ends of each cylinder bore in the arrangement direction.
The internal combustion engine according to claim 14, wherein the guide grooves are provided on the inner peripheral surfaces of the hollow portion of the cylinder block main body on both ends in the longitudinal direction of the opening of the hollow portion. A fixing collar portion is provided on the inner peripheral surface of the hollow portion of the cylinder block main body along a direction parallel to the penetrating direction of the hollow portion.
The internal combustion engine according to any one of claims 11 to 13, wherein a guide groove for fitting with the fixing collar portion is provided on the outer peripheral surface of the connecting cylinder. The fixing collars are provided on the inner peripheral surfaces of the hollow portion of the cylinder block body on both ends in the longitudinal direction of the opening of the hollow portion.
The internal combustion engine according to claim 16, wherein the guide grooves are provided on the outer peripheral surfaces of the connecting cylinders on both ends in the arrangement direction of the cylinder bores provided in the connecting cylinders. The internal combustion engine according to claim 15 or 17, wherein the engine is a horizontally opposed engine. The invention according to any one of claims 11 to 18, wherein a coolant jacket is provided between the outer peripheral surface of the connecting cylinder and the inner peripheral surface of the hollow portion of the cylinder block main body. Internal combustion engine. A split collar that divides the coolant jacket into two or more portions is provided on at least one surface selected from the outer peripheral surface of the connecting cylinder and the inner peripheral surface of the hollow portion of the cylinder block body. The internal combustion engine according to claim 19, wherein the engine is provided. The internal combustion engine according to claim 20, wherein the split collar portion does not have a through hole penetrating in the width direction of the split collar portion. The internal combustion engine according to claim 20, wherein the split collar portion has a through hole penetrating in the width direction of the split collar portion and a closing member capable of closing the through hole. The internal combustion engine according to claim 22, wherein the through hole is closed by the closing member when the internal combustion engine is in operation. The internal combustion engine according to any one of claims 20 to 23, wherein the coolant jacket spacer is not arranged in the coolant jacket. The claim is characterized in that the depth D of the coolant jacket is ½ or less of the total length L of the coolant jacket in a direction parallel to the center line of each cylinder bore provided in the connecting cylinder. The internal combustion engine according to any one of 20 to 24. The depth D of the coolant jacket is ½ or less of the total length L of the coolant jacket in the direction parallel to the center line of each cylinder bore provided in the connecting cylinder, and the coolant jacket. The internal combustion engine according to any one of claims 20 to 25, wherein the coolant jacket spacer is not arranged therein. A connecting cylinder comprising two or more cylinder liners and a connecting portion for connecting the two or more cylinder liners to each other. It has an annular outer peripheral shape with an enlarged bore diameter of each cylinder liner.
In the direction of the center line of each cylinder liner, the outer diameter D1 with respect to the center line of each cylinder liner in the first region consisting of the outer peripheral surface from the vicinity of the cylinder head side to the vicinity of the central portion is the outer circumference near the crank chamber side. Larger than the outer diameter D2 relative to the centerline of each cylinder liner in the second region of surfaces,
The connecting cylinder according to claim 27, wherein a step parallel to and continuous with the outer peripheral direction is formed between the first region and the second region. A connecting cylinder characterized by including a connecting cylinder main body provided with two or more cylinder bores and a coating film covering an inner peripheral surface of the connecting cylinder main body provided with the cylinder bore. Includes a connecting cylinder body provided with two or more cylinder bores and a coating covering the inner peripheral surface of the connecting cylinder body provided with the cylinder bores.
It has an annular outer peripheral shape with an enlarged bore diameter of each cylinder bore.
In the direction of the center line of each cylinder bore, the outer diameter D1 with respect to the center line of each cylinder bore in the first region consisting of the outer peripheral surface from the vicinity of the cylinder head side to the vicinity of the central portion is from the outer peripheral surface near the crank chamber side. Larger than the outer diameter D2 relative to the centerline of each cylinder bore in the second region
The connecting cylinder according to claim 29, wherein a step parallel to and continuous with the outer peripheral direction is formed between the first region and the second region. The connecting cylinder according to any one of claims 27 to 30, wherein a collar portion is provided on the outer peripheral surface. 28 or 30. The connection according to claim 28 or 30, wherein the first region is provided with a flange portion that divides the first region into a region on the cylinder head side and a region on the crank chamber side. Cylinder. The connecting cylinder according to claim 31 or 32, wherein the collar portion does not have a through hole penetrating in the width direction of the collar portion. The connecting cylinder according to claim 31 or 32, wherein the collar portion has a through hole penetrating in the width direction of the collar portion and a closing member capable of closing the through hole. A coolant passage is provided between the two cylinder bores of the connecting cylinders adjacent to each other, inside the end face on the side where the cylinder head of the connecting cylinder is arranged, and at the same time.
The invention according to any one of claims 27 to 34, wherein the cross-sectional shape of the coolant passage in a plane parallel to the center line of each cylinder bore provided in the connecting cylinder is a slit shape. Connecting cylinder.

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