WO2019142270A1

WO2019142270A1 - Internal combustion engine manufacturing method, internal combustion engine, and coupling cylinder

Info

Publication number: WO2019142270A1
Application number: PCT/JP2018/001243
Authority: WO
Inventors: 正巳堀米; 佐藤　陽; 貴志大泉; 高志井上; 顕彦根
Original assignee: Ｔｐｒ株式会社; Ｔｐｒ工業株式会社
Priority date: 2018-01-17
Filing date: 2018-01-17
Publication date: 2019-07-25
Also published as: EP3741980A1; CN111406151A; JPWO2019142270A1

Abstract

The present invention enhances the ease of maintenance and the recycle-ability of an internal combustion engine and increases the degree of freedom of designing internal combustion engines. Provided is an internal combustion engine manufacturing method for manufacturing an internal combustion engine 100, the method comprising at least a fitting step for fitting, to a hollow portion 64 of a cylinder block body 60 that has a crank chamber 62 formed on one end side thereof, that has a cylinder head attached thereto on the other end side, and that has the hollow portion 64 provided therein so as to penetrate the cylinder block body 60 from the one end side to the other end side, a coupling cylinder 10 being selected from the group consisting of: (1) a first coupling cylinder including two or more cylinder liners and a coupling part for coupling the two or more cylinder liners to each other; and (2) a second coupling cylinder including a coupling cylinder body part provided with two or more cylinder bores and including a coating that covers the inner circumferential surface of the coupling cylinder body part in which the cylinder bores are provided. Also provided are an internal combustion engine manufactured by said method, and a coupling cylinder used therefor.

Description

Method of manufacturing internal combustion engine, internal combustion engine and coupling cylinder

The present invention relates to a method of 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 in which cylinder liners forming adjacent cylinder bores are integrally coupled is known. It is done. As a method of manufacturing such a cylinder block, for example, (1) after setting an assembly of cylinder liners in a mold at the time of casting a cylinder block, fixing it to the cylinder block body by casting around the cylinder block body Methods and (2) methods of fixing a cylinder liner assembly to a cylinder body by fitting are known (Patent Documents 1 and 2). In the method of manufacturing the cylinder block described in these Patent Documents 1 and 2, a plurality of cylinder liners are integrally formed, and a cylinder liner assembly formed of one member is used.

Patent No. 2813947 Patent No. 4278125

On the other hand, in the internal combustion engine, it is necessary to satisfy various performances in accordance with the required specifications of the vehicle in which the internal combustion engine is used or equipment other than the vehicle. For this purpose, when designing an internal combustion engine, it is advantageous if the degree of freedom is high. In addition, internal combustion engines are also required to be excellent in maintainability. Furthermore, in recent years, recyclability is also required of internal combustion engines from the viewpoint of environmental load. However, when the present inventors examined, in the method for manufacturing a cylinder block described in Patent Documents 1 and 2 or an internal combustion engine manufactured using the same, all three of maintainability, recyclability and design freedom are all considered. It proved to be difficult to satisfy.

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

The above object is achieved by the present invention described below. That is,
A method of manufacturing an internal combustion engine according to the present invention comprises: (1) a first connecting cylinder including two or more cylinder liners and a connecting portion connecting two or more cylinder liners to each other; and (2) two or more Any of the connecting cylinders selected from the group consisting of: a second connecting cylinder including a connecting cylinder body provided with the first cylinder bore and a coating covering the inner peripheral surface of the connecting cylinder body provided with the cylinder bore; The crank chamber is formed on one end side, the cylinder head is assembled on the other end side, and the fitting step is fitted to the hollow portion of the cylinder block main body provided with the hollow portion penetrating from one end side to the other end side To produce an internal combustion engine at least.

In one embodiment of the method of manufacturing an internal combustion engine according to the present invention, preferably, two or more cylinder liners and the connecting portion are integrally and inseparably formed.

In another embodiment of the method of manufacturing an internal combustion engine according to the present invention, preferably, the connecting portion covers the entire outer peripheral surface of the two or more cylinder liners.

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

In another embodiment of the method of manufacturing an internal combustion engine according to the present invention, preferably, the material forming the connecting cylinder main body is a material different from the material forming the cylinder block main body.

In another embodiment of the method of manufacturing an internal combustion engine according to the present invention, it is preferable that the fitting process be performed in any fitting mode selected from a loose fit, an intermediate fit and a tight fit.

In another embodiment of the method for manufacturing an internal combustion engine according to the present invention, the connecting cylinder is a 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 performed only before the fitting process.

In another embodiment of the method for manufacturing an internal combustion engine according to the present invention, the connecting cylinder is the first connecting cylinder, and the surface of the film is formed after performing a film forming step of forming a film 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 finish processing, 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 the second connecting cylinder, and the surface of the coating covering the inner peripheral surface of the connecting cylinder body provided with the cylinder bore is finished. It is preferable to carry out the sliding surface forming step of forming the sliding surface accordingly only before the fitting step.

In another embodiment of the method of manufacturing an internal combustion engine according to the present invention, it is preferable that the fitting step be performed by any fitting method selected from a loose fit and an intermediate fit.

In another embodiment of the method of manufacturing an internal combustion engine according to the present invention, it is preferable that the fitting step be performed by close fitting.

In another embodiment of the method for manufacturing an internal combustion engine according to the present invention, the connecting cylinder is a 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 performed only after the fitting process.

In another embodiment of the method for manufacturing an internal combustion engine according to the present invention, the connecting cylinder is the first connecting cylinder, and the surface of the film is formed after performing a film forming step of forming a film 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 finish processing, 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 the second connecting cylinder, and the surface of the coating covering the inner peripheral surface of the connecting cylinder body provided with the cylinder bore is finished. It is preferable to carry out the sliding surface forming step of forming the sliding surface accordingly only after the fitting step.

In another embodiment of the method for manufacturing an internal combustion engine according to the present invention, the sliding surface forming step is performed in a state where at least the connecting cylinder is heated while assembling the connecting cylinder to a jig simulating the cylinder block body and cylinder head. Preferably.

Another embodiment of the method of manufacturing an internal combustion engine according to the present invention carries out at least the step of forming a coolant passage, which forms a coolant passage between two adjacent cylinder bores of the connecting cylinder, at least before the fitting step. It is preferable to do.

In another embodiment of the method of manufacturing an internal combustion engine according to the present invention, the coolant passage is provided inside the end face on the side where the cylinder head of the connecting cylinder is disposed, 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 above is slit-like.

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

The internal combustion engine of the present invention comprises: (1) a first connecting cylinder including two or more cylinder liners and a connecting portion connecting the two or more cylinder liners to each other; and (2) two or more cylinder bores A connecting cylinder selected from the group consisting of a provided connecting cylinder body and a second connecting cylinder including a coating covering the inner peripheral surface of the connecting cylinder body provided with a cylinder bore, and one end At least a cylinder block main body having a crank chamber formed on one side, a cylinder head assembled on the other end, and a hollow portion penetrating from one end to the other end, the connecting cylinder being the 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 according to the present invention, preferably, the connecting cylinder is fitted in the hollow portion of the cylinder block body in any fitting method selected from a loose fit and an intermediate fit.

In another embodiment of the internal combustion engine according to the present invention, the coolant passage is provided between the two adjacent cylinder bores of the connecting cylinder inside the end face on the side where the cylinder head of the connecting cylinder is disposed. Preferably, 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.

In another embodiment of the internal combustion engine according to the present invention, a fixing flange 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. It is preferable that a guide groove fitted to the fixing collar portion be provided on the inner peripheral surface of the hollow portion.

In another embodiment of the internal combustion engine according to the present invention, the fixing flanges are provided on the outer peripheral surface of the connecting cylinder at both end sides in the arrangement direction of each cylinder bore, and the guide groove is in the longitudinal direction of the opening of the hollow portion. It is preferable to be provided on the inner peripheral surface of the hollow portion of the cylinder block main body at both end sides.

In another embodiment of the internal combustion engine according to the present invention, a fixing flange 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. Preferably, a guide groove fitted to the fixing collar portion is provided.

In another embodiment of the internal combustion engine according to the present invention, the fixing flanges are provided on the inner peripheral surface of the hollow portion of the cylinder block main body at both ends in the longitudinal direction of the opening of the hollow portion, and the guide groove is the connecting cylinder It is preferable to be provided on the outer peripheral surface of the connecting cylinder at both end sides of the respective cylinder bores provided in the arrangement direction of the cylinder bores.

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

In another embodiment of the internal combustion engine according to the present invention, preferably, 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 according to the present invention, the dividing collar for dividing the coolant jacket into two or more parts 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. Preferably, it is provided on at least one of the surfaces.

In another embodiment of the internal combustion engine of the present invention, preferably, the fixing collar also has a function of a dividing collar.

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

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

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

In another embodiment of the internal combustion engine of the present invention, preferably, no coolant jacket spacer is 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 not more than 1/2 times 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 preferred.

In another embodiment of the internal combustion engine of the present invention, the depth D of the coolant jacket is not more than 1/2 times 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. Preferably, no coolant jacket spacer is arranged in the coolant jacket.

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

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

In another embodiment of the internal combustion engine of the present invention, the first connection cylinder has a continuous annular outer peripheral shape in which the bore diameter of each cylinder liner is enlarged, and the cylinder in the centerline direction of each cylinder liner An outer diameter D1 based on a center line of each cylinder liner in a first region consisting of an outer peripheral surface from near the head side to a central portion vicinity is each cylinder liner in a second region consisting of an outer peripheral surface near the crank chamber side Between the first region and the second region, a step parallel to and continuous with the outer peripheral direction is formed between the first region and the second region, and is further formed with the first region and the second region. Preferably, a coolant jacket is formed between the inner circumferential surface of the hollow portion of the cylinder block body and the inner circumferential surface of the hollow portion.

In another embodiment of the internal combustion engine of the present invention, the second connecting cylinder has a continuous annular outer peripheral shape in which the bore diameter of each cylinder bore is enlarged, and the cylinder head side in the center line direction 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 central portion vicinity is the center line of each cylinder bore in the second region consisting of the outer peripheral surface near the crank chamber side A step which is larger than the reference outer diameter D2 and is continuous 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 body It is preferable that a coolant jacket be formed between the inner circumferential surface of the hollow portion and the hollow portion.

In another embodiment of the internal combustion engine according to the present invention, a flange portion for dividing the first region into a region on the cylinder head side and a region on the crank chamber side is provided in the first region. Preferably, the liquid jacket is divided with respect to the centerline direction of the cylinder liner or the cylinder bore.

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

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

The connecting cylinder according to the second aspect of the present invention is characterized by including 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 bore. .

One embodiment of the connecting cylinder of the second invention of the present invention has a continuous annular outer peripheral shape in which the bore diameter of each cylinder bore is expanded, and from the vicinity of the cylinder head side to the vicinity of the central portion in the centerline direction 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 surfaces up to 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 a step parallel to and continuous with the outer circumferential direction be formed between the first region and the second region, which is larger than D2.

In one embodiment of the connecting cylinder of the first and second inventions, 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 which divides the first region into a region on the cylinder head side and a region on the crank chamber side Is preferred.

In the other embodiments of the connecting cylinder of the first and second inventions, it is preferable that the ridge portion does not have a through hole penetrating in the width direction of the ridge 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 cylinder according to the first and second inventions, the coolant passage is provided between the two cylinder bores of the connecting cylinder adjacent to each other from the end face of the connecting cylinder on which the cylinder head is disposed. It is preferable that the cross-sectional shape of the cooling fluid passage in a plane parallel to the center line of each cylinder bore provided in the connecting cylinder is a slit shape.

Other embodiments of the connecting cylinder of the first and second inventions preferably have no protrusions in the first region.

Other embodiments of the first and second inventive connection cylinders preferably do not have protrusions in the second region.

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

It is an external appearance perspective view which shows an example of the 1st connection cylinder used for the manufacturing method of the internal combustion engine of this embodiment. It is an enlarged perspective view of the cylinder head side vicinity of the 1st connection cylinder shown in FIG. FIG. 3 is an enlarged cross-sectional view showing an example of a cross-sectional structure taken along the line III-III of the first coupled cylinder shown in FIG. 2; It is an expansion perspective view showing an example near the cylinder head side of the 2nd connecting cylinder used for a manufacturing method of an internal-combustion engine of this embodiment. FIG. 5 is an enlarged cross-sectional view showing an example of a cross-sectional structure taken along the line VV of the second connection cylinder shown in FIG. 4; It is a disassembled perspective view which fractures | ruptures and shows a part of cylinder block main body about an example of the cylinder block main body used for the manufacturing method of the internal combustion engine of this embodiment. It is an appearance perspective view showing an example of an internal-combustion engine using the 1st connecting cylinder manufactured by the manufacturing method of an internal-combustion engine of this embodiment. FIG. 8 is a schematic cross sectional view showing an example of a cross sectional structure taken along the line VIII-VIII of the internal combustion engine shown in FIG. 7; FIG. 5 is a schematic cross-sectional view showing an example of a cross-sectional structure between a symbol IX and a symbol IX of the first coupled cylinder shown in FIG. 3; It is a schematic cross section which shows an example of the cross-section between the code | symbol XX of a 2nd connection cylinder shown in FIG. It is a schematic cross section which shows one modification of the 1st connection cylinder shown in FIG. It is a schematic cross section which shows one modification of the internal combustion engine shown in FIG. It is a schematic cross section which shows the other modification of the internal combustion engine shown in FIG. It is a model end view which shows an example of the cross-sectional shape of the channel for coolants, and is a figure shown about the expansion end face (ZX section) in the end face neighborhood of the other end side (Z1 side) of the 1st connection cylinder. Here, FIG. 14 (A) is an end view showing a coolant passage having a circular cross-sectional shape, and FIG. 14 (B) is an opening also in the end face of the other end side (Z1 side) of the connecting cylinder. 14C is an end view showing a passage for a coolant having a slit-like cross-sectional shape having a portion, and FIG. 14C is an inner side (an end side (Z2 side) than an end face of the other end side (Z1 side) of the connecting cylinder 10. 2.) It is an end view showing a passage for coolant having a slit-like cross-sectional shape provided. It is an external appearance perspective view which shows the other modification of the 1st connection cylinder shown in FIG. It is an external appearance perspective view which shows the other modification of the 1st connection cylinder shown in FIG. It is an external appearance perspective view which shows the other modification of the 1st connection cylinder shown in FIG. It is a top view which shows an example of the cylinder block main body used combining with the 1st connection cylinder shown in FIG.

Hereinafter, a method of manufacturing an internal combustion engine, an internal combustion engine, and a connecting cylinder of the present embodiment will be described with reference to the drawings. In the following description, the X direction, the Y direction, and the Z direction shown in the drawings are directions 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 connection cylinder, the center line C of the cylinder bore and cylinder liner) And the Z direction is a direction parallel to the center line C of the cylinder bore. In the X direction, the X1 side is opposite to the X2 side, and 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 It is the opposite direction to (the crank chamber side).

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

FIGS. 1 to 3 are schematic views showing an example of a connecting cylinder used in the method of manufacturing an internal combustion engine of the present embodiment, and more specifically, a view for explaining 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. 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 connection cylinder, and is a cross-sectional structure in which the first connection cylinder is cut along the line III-III in FIG. XY cross section structure is shown.

The first connecting cylinder 10A1 (10A, 10) illustrated in FIGS. 1 to 3 is provided with four cylinder bores 20, and in each cylinder bore 20, the center lines C of each are 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 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 at least cover the entire outer peripheral surface 40 A of each of the four cylindrical cylinder liners 40, and the bores of the respective cylinder liners 40. It has a continuous annular outer peripheral shape in which the diameter Db is expanded. In addition, one cylinder liner 40 and another cylinder liner 40 adjacent to each other in the X direction are spaced apart by a predetermined distance so that the outer peripheral surfaces 40A do not contact each other. That is, the space between the two cylinder liners 40 adjacent to each other is filled with the material of the connecting portion 42 without any gap. Further, the end face on the cylinder head side and the crank chamber side of the cylinder liner 40 is also covered by the connecting portion 42. However, the end face of the cylinder liner 40 does not have to be covered by the connecting portion 42 either or both of the end faces on the cylinder head side and the crank chamber side.

FIGS. 4 to 5 are schematic views showing another example of the connecting cylinder used in the method of manufacturing an internal combustion engine according to the present embodiment, and specifically, a view 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 connection cylinder. 5 is an enlarged cross-sectional view showing an example of the cross-sectional structure in the vicinity of the cylinder head side of the second connection cylinder, and the cross-sectional structure in which the connection cylinder is cut between the symbols V and V in FIG. ) Is shown.

The outer peripheral shape of the second connection cylinder 10B (10) illustrated in FIGS. 4 to 5 is the same as the first connection cylinder 10A1 illustrated in FIG. And four cylinder bores 20 are provided also in the 2nd connection cylinder 10B, and each cylinder bore 20 is along the X direction so that that center line C may be located on the same plane (XZ plane). It is arranged. Further, the second connecting cylinder 10B includes a connecting cylinder body 50 provided with four cylinder bores 20, and a coating 52 covering the inner circumferential surface 50B provided with the cylinder bore 20 of the connecting cylinder body 50. In the examples shown in FIGS. 4 to 5, the connecting cylinder main body 50 has a continuous annular outer peripheral shape in which the bore diameters Db of the four circular bore cylinder bores 20 are expanded.

Although the first connecting cylinder 10A1 illustrated in FIGS. 1 to 3 shows the case where four cylinder liners 40 are provided, the number of cylinder liners 40 is not particularly limited as long as it is two or more. Can be selected in the range of about 2-8. 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 two or more. Can be selected in the range of about 2-8.

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

Here, as illustrated in FIG. 6, a crank chamber 62 is formed at one end side (Z2 side) in the cylinder block main body 60A (60), and a cylinder head is assembled at 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 process, the connecting cylinder 10 is fitted in the hollow portion 64. In addition, after the fitting process is performed, the internal combustion engine is completed by further performing various other processes. As another process, for example, a process of assembling a cylinder head to 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 process, the connecting cylinder 10 can be fitted to the hollow portion 64 of the cylinder block body 60 by any fitting method selected from a loose fit, an intermediate fit and a tight fit. Here, in the specification of the present application, “spacing fit” is a fitting in which a gap is generated between members even in consideration of the tolerance of each member to be fitted, and “squeezing fit” is: Interfering is a fitting that causes an interference between the members even in consideration of the tolerance of each member to be fitted, and “intermediate fit” means the tolerance in each member to be fitted, Both when there is a gap between the members and when there is interference is a fit (intermediate fit between a loose fit and a tight fit).

The fitting method by tight fitting is not particularly limited. For example, the coupling cylinder 10 in a cooled state is fitted in the hollow portion 64 of the cylinder block main body 60 by cold fitting, and the cylinder in a state where the coupling cylinder 10 is heated Examples of the method include shrink fitting to be fitted into the hollow portion 64 of the block main body 60 and strong press-fit. Although the fitting method by the intermediate fitting is not particularly limited, for example, after the fitting in a state in which the sliding of the fitting portion is improved using a lubricant or the like, or after performing positioning with high accuracy, the connecting cylinder For example, fitting using a jig made of a material softer than 10 (for example, driving using a resin or wooden hammer, etc.), etc. Further, the connection cylinder 10 is mounted on the cylinder block main body 60 by loose fitting. When fitting in the hollow portion 64, fitting is performed in a state in which a deformable or easily flowable material including a resin material, a rubber material, a fibrous material such as glass fiber, a paste-like material, etc. is disposed between both members as needed. A combination may be performed.

Which fitting method is selected can be selected according to the required design specifications of the internal combustion engine 100 or the like. When it is desired to firmly fix the connecting cylinder 10 to the cylinder block main body 60, tight fitting is preferable. In the case where fitting by tight fitting is preferable, for example, in a state where the internal combustion engine 100 is attached to equipment such as a car such as a V-type engine or a horizontally opposed engine, and at the time of assembly. In general, the case where the center line C of the cylinder bore is greatly inclined or perpendicular to the vertical direction can be exemplified.

On the other hand, in a state where internal combustion engine 100 is attached to a device such as an automobile and at the time of assembly, internal combustion engine 100 has a configuration in which the vertical direction and center line C of the cylinder bore are parallel or substantially parallel. It is easy to stably fix the connecting cylinder 10 in the cylinder block main body 60 without causing positional deviation of the connecting cylinder 10 in the direction orthogonal to the center line C of the cylinder bore. In such a case, loose fitting is also suitable. In addition, in the state where internal combustion engine 100 is attached to a device such as a car, the internal combustion engine 100 usually has a configuration in which the center line C of the cylinder bore is largely inclined or orthogonal to the vertical direction. At the time of assembly of internal combustion engine 100 (particularly preferably, a period from immediately before attaching coupling cylinder 10 to cylinder block body 60 to completion of cylinder head assembly), the vertical direction and center line C of the cylinder bore are parallel or substantially parallel. In the case where they are arranged in such a way, a loose fit is also suitable. Further, as compared with tight fit and middle fit, loose fit is less likely to cause breakage of the joint portion between connecting cylinder 10 and cylinder block main body 60 when disassembling internal combustion engine 100, so that the parts are reworked. It is also advantageous in terms of use.

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

Furthermore, when fitting the connecting cylinder 10 to the hollow portion 64, the outer peripheral surface 10S at one end side (Z2 side) of the connecting cylinder 10 is made to be a tapered surface in order to improve the positioning and insertion of the connecting cylinder 10 with respect to the hollow portion 64. Is also suitable.

FIG. 7 shows an external perspective view showing an example of an internal combustion engine manufactured by the method of manufacturing an internal combustion engine according to the present embodiment, and FIG. 8 shows the case where the internal combustion engine shown in FIG. It is a schematic cross section which shows an example of a cross-section (YZ cross section structure). In the internal combustion engine shown in FIGS. 7 and 8, the description of the 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. The connecting cylinder 10 is a portion on one end side of the hollow portion 64 of the cylinder block main body 60. It is detachably fitted in (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. However, 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. 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. However, in the case of using the connecting cylinder 10 having the flange portion 16, a diagram to be described later A cylinder block body 60B (60) as exemplified 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, the internal combustion including the cylinder liner and the cylinder block even if repair and replacement work of a part of the internal combustion engine becomes necessary. It is necessary to handle the main part of the engine. In addition to this, in a general internal combustion engine, two or more kinds of different materials (for example, a material forming a cylinder liner and a material forming a cylinder block in which a cylinder liner is cast) are integrally and inseparably It is configured. For this reason, when it is going to carry out recycling processing for every kind of material, it is necessary to separate according to every kind of material by utilizing the difference in the dissolution temperature of the material. This point is the same as in the internal combustion engine disclosed in Patent Document 1 having a structure in which a cylinder liner assembly is cast in a cylinder block body.

On the other hand, in the method of manufacturing an internal combustion engine according to the present embodiment, as illustrated in FIGS. 7 and 8, the connection cylinder 10 is fitted to the hollow portion 64 when the connection cylinder 10 is fixed to the cylinder block main body 60. Is done. 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 maintaining internal combustion engine 100, connecting cylinder 10 can be removed from cylinder block main body 60, and either or both of connecting cylinder 10 and cylinder block main body 60 can be repaired or replaced separately. For this reason, the internal combustion engine 100 manufactured by the method for manufacturing an internal combustion engine of the present embodiment is excellent in maintainability.

In addition to this, when the internal combustion engine 100 is disposed of, it is possible to easily separate and dispose separately the connecting cylinder 10 and the cylinder block main body 60 which are main components of the internal combustion engine 100. Here, the cylinder block main body 60 used in the method for manufacturing an internal combustion engine according to the present embodiment is usually a member manufactured using casting, resin molding or the like (a member made of one type of integral material). It consists of

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

If any one member 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 of the members is reused and only the other member is disposed of It is also possible.

From the viewpoint of easy separation and disassembly of the connecting cylinder 10 and the cylinder block main body 60 at the time of recycling or disposal of the internal combustion engine 100, the connecting cylinder 10 is loosely fitted to the hollow portion 64 of the cylinder block main body 60. It is preferable to be fitted by any fitting method selected from the middle fitting, and it is further preferable to be fitted by a loose fitting.

On the other hand, when recycling or disposing of 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 tight fitting, a process opposite to cold fitting and / or shrink fitting Is preferred. 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 disassembling method of 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 fitting or gap fitting, if necessary. May be

Further, in a conventional general internal combustion engine manufacturing method in which an internal combustion engine is manufactured by integrating a cylinder liner and a cylinder block by casting the cylinder liner, defects are found only in the cylinder liner portion or in the vicinity thereof after casting. However, 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 of manufacturing an internal combustion engine according to the present embodiment, the internal combustion engine 100 is manufactured by combining two components (the connection cylinder 10 and the cylinder block body 60) after preparing them. Therefore, even if a defect defect is found in any of the parts after the fitting process is finished, only the part in which the defect 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 lightness according to the required specification of the vehicle in which the internal combustion engine is used or equipment other than the vehicle. In addition to this, characteristics particularly important for an internal combustion engine such as output and fuel efficiency tend to be greatly influenced by the material and structure near the cylinder bore. Therefore, in the internal combustion engine, it is important that the design freedom is high, particularly, the design freedom near the center of the internal combustion engine (near the cylinder bore) is high so that various performances can be flexibly satisfied. .

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

Therefore, a general-purpose internal combustion engine having a structure in which both members are integrally formed and a plurality of cylinder liners are integrally formed by casting the cylinder liner into a cylinder block, and is configured from one member. The internal combustion engine 100 manufactured by the method of manufacturing an internal combustion engine according to the present embodiment has a high degree of freedom in design as compared with the internal combustion engines disclosed in Patent Documents 1 and 2 which use an assembly of cylinder liners. Therefore, the internal combustion engine 100 can easily meet a wide variety of required specifications.

Internal combustion engine 100 is not limited to a specific design specification, and can be designed flexibly based on various required specifications or technical concepts. Examples of the design of the internal combustion engine 100 include, for example, the design examples shown below as basic technical concepts.

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

(Design example 2)
a) Connecting cylinder 10 used for 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, thinning of the cylinder liner 40 and thinning of the thickness between two adjacent cylinder bores 20 are facilitated, and as a result, weight reduction of the internal combustion engine 100 can be achieved. Alternatively, in the case where the thickness between the two adjacent cylinder bores 20 is not reduced, when the cooling medium flow path is provided between the two adjacent cylinder bores 20, the necessary strength for the first connecting cylinder 10A is secured. However, the volume of the cooling medium channel can be increased. In addition, it is possible to suppress bore deformation due to an increase in in-cylinder pressure due to engine combustion.

(Design example 3)
As a connecting cylinder 10 used for the internal combustion engine 100, a second connecting cylinder 10B is used.
In this design example 3, the sliding characteristics can be ensured by the coating 52 whose mass is substantially negligible compared to the cylinder liner 40. For this reason, in the internal combustion engine, a structural part in the vicinity of the part where the cylinder bores are arranged: that is, a part consisting of the cylinder liner and a cast member covering the cylinder liner in a conventional general internal combustion engine Compared to the portion consisting of the first connecting cylinder 10A and the connecting portion 42 provided so as to cover the whole surface of the cylinder liner 40 and the outer peripheral surface 40A of the cylinder liner 40, the portion consisting of the second connecting cylinder 10B It is easy to reduce the mass and volume significantly. Therefore, remarkable weight reduction and miniaturization of the internal combustion engine 100 can be achieved.

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

(Design example 5)
a) Connecting cylinder 10 used for internal combustion engine 100: First connecting cylinder 10A.
b) Materials constituting the connecting portion 42 and the cylinder liner 40: A metal material having high strength is used.
c) Simplification of the structure of the cylinder block body 60 (for example, the groove 66 is omitted in the cylinder block body 60A shown in FIG. 6).
In Design Example 5, since the strength of the first connection cylinder 10A is high, it is possible to suppress the bore deformation even with a high in-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 of 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 integrally inseparable (in other words, non-detachable) or may be configured to be removable. Good. (A) In the case where the first connection cylinder 10A is a member formed so that two or more cylinder liners 40 and the connection portion 42 form an integral part, each cylinder liner 40 and the connection portion 42 An interface (bonding interface) for bonding both members is formed between them. (B) Also, in the case where the first connection cylinder 10A is a member in which two or more cylinder liners 40 and the connection portion 42 are formed so as to be removable, between each cylinder liner 40 and the connection portion 42 In this case, an interface (contact interface) in which both members are simply in contact with each other is formed. In each of the cases (a) and (b), each cylinder liner 40 and the connecting portion 42 are discontinuous members. 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 to 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 placing two or more cylinder liners 40 in a mold, pour molten metal into the mold and cast two or more cylinder liners 40 with a cast material such as cast iron or aluminum alloy Two or more cylinder liners 40, such as b) by disposing two or more cylinder liners 40 in a mold and injecting or injecting a molten resin material into the mold; It is possible to obtain the first connection cylinder 10A in which the connection portion 42 is formed integrally and indivisiblely. In this case, the connecting portion 42 can cover the entire outer peripheral surface 40A of the cylinder liner 40 by appropriately selecting the shape of the mold, or can cover only a part of the outer peripheral surface 40A of the cylinder liner 40. it can.

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

However, it is preferable that the connecting portion 42 be formed by casting (for example, die casting, gravity casting, etc.) rather than using a member having a shape formed in a continuous ring shape in advance. In this case, the number of parts can be reduced when manufacturing the first connecting cylinder 10A. In addition to this, in the case where the connecting portion 42 is formed integrally with the cylinder liner 40 by casting as compared with the case of using a member having a shape formed in a continuous annular shape 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, the cooling performance of the internal combustion engine 100 can be easily improved. When forming the connection part 42 by casting, in order to improve the joint strength of the connection part 42 and the cylinder liner 40, in the outer peripheral surface 40A of the cylinder liner 40, protrusion with a height of about 0.1 mm-1.5 mm Or a groove or recess with a depth of about 0.1 mm to 1.5 mm.

Although the thickness of the cylinder liner 40 can be selected appropriately, it 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, for the second connection cylinder 10B, for example, after manufacturing the connection cylinder main body 50 by casting, the film 52 is formed to cover the inner peripheral surface 50B provided with the cylinder bore 20 of the connection cylinder main body 50. Do. A known film forming method such as a thermal spraying method can be appropriately used to form the film 52. The thickness of the coating 52 can be selected as appropriate, but it is generally in the range of about 0.02 mm to 0.2 mm. In this case, for example, when a thermal spraying method is employed as a method for forming the film 52, the thickness of the film 52 is preferably about 0.1 mm to 0.2 mm, and PVD (Physical Vapor Deposition) as a method for forming the film 52. When the method or the CVD (Chemical Vapor Deposition) method is employed, the thickness of the film 52 is preferably about 0.02 mm to 0.03 mm. Moreover, as a film formation method of the film 52, a plating method can also be used. In this case, the thickness of the coating 52 is preferably about 0.02 mm to 0.2 mm. Further, as the film 52 made of a plating film, for example, a Cr-based plating film, a plating film containing Ni and SiC (so-called Nicadyl plating film) and the like can be mentioned.

In the first connecting cylinder 10A, the material forming the connecting portion 42 may be the same material as the material forming the cylinder block main body 60, but is different from the material forming the cylinder block main body 60 Is particularly preferred. Similarly, in the second connecting cylinder 10B, the material forming the connecting cylinder main body 50 may be the same material as the material forming the cylinder block main body 60, but with the material forming the cylinder block main body 60 Particular preference is given to different materials.

In the specification of the present application, “two kinds of materials are different from each other” means a) when the composition of each material is fundamentally different, such as a) aluminum alloy and steel, b) the same composition type In the material, for example, even if two types of aluminum alloys, one is an aluminum alloy having a high Al content, and the other is an aluminum alloy having a low Al content, c) In materials of the same composition and the same quantitative composition, the degree of crystallinity-amorphism, the type of crystal phase, or the difference in the other structure exist in one material and the other material. Or if d) one material and the other material contain the same material X, such as plastic and fiber reinforced plastic, one material is the material It consists of a single material consisting only if the other material is a composite material including other materials 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 of the first connecting cylinder 10A, and the connecting cylinder main portion 50 of the second connecting cylinder 10B) is different from the material of the cylinder block main body 60 By doing this, the design freedom of the entire internal combustion engine 100 can be further improved. Therefore, for example, it becomes extremely easy to manufacture an internal combustion engine 100 of various specifications as exemplified in the following (1) to (3).
(1) An internal combustion engine having a specification that reduces the cost and weight of the cylinder block main body 60 by using a material having high rigidity relative to the cylinder block main body 60 as a material constituting the main part of the connecting cylinder 10 100.
(2) By using a material having high thermal conductivity relative to the main part of the connecting cylinder 10 as the material forming the cylinder block main body 60, the internal combustion of the specification whose load on the cooling system at high load is reduced Institution 100.
(3) By using a material having a low thermal conductivity relative to the main part of the connecting cylinder 10 as the material constituting the cylinder block main body 60, the coolant temperature rise during low load and warm air can be accelerated to improve fuel consumption The internal combustion engine 100 with improved specifications.

As a material which constitutes connecting part 42 or connecting cylinder main part 50, metal materials, such as aluminum alloy (preferably high rigidity type aluminum alloy), magnesium alloy, steel, etc. are mentioned, for example, and cylinder block main body 60 is constituted. Materials include metal materials such as aluminum alloy and magnesium alloy, resin materials, organic-inorganic composite materials including resin and inorganic materials (for example, inorganic fillers such as glass fibers or carbon fibers in a heat resistant resin matrix such as phenol resin) And the like) and the like.

Further, from the viewpoint of suppressing the deformation of the cylinder bore 20 during operation of the internal combustion engine 100, the thermal expansion coefficient of the material forming the cylinder block main body 60 is the heat of the material forming the connecting portion 42 of the first connecting cylinder 10A. 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 portion 50 of the second connecting cylinder 10B. Is preferred.

Moreover, as a material which comprises the cylinder liner 40, cast iron materials, such as flake graphite cast iron, are mentioned, Although various well-known hard materials can be utilized without restriction as a material which comprises the film 52, For example, the film 52 In the case of film formation by the thermal spraying method, Fe-based, WC-based, etc. may be mentioned, and in the case of forming the film 52 by PVD or CVD, C-based, Cr-based, etc. may be mentioned. The layer structure of the film 52 is also 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 of manufacturing an internal combustion engine according to the present embodiment, as illustrated in FIGS. 6 to 8, the crank chamber 62 is formed at one end and the cylinder head is assembled at the other end. The structure is not particularly limited as long as it has a hollow portion 64 penetrating from one end side to the other end side and has a structure in which the connecting cylinder 10 can be fitted and fitted in the hollow portion 64. Moreover, although the cylinder block main body 60 can be manufactured using a well-known method suitably, it is preferable to manufacture by casting or resin molding. In addition, as a specific example of other manufacturing methods other than casting and resin molding, for example, a hot pressing process or HIP (Hot Isostatic Pressing) process using raw material powder, lamination of a layer made of raw material powder and laser sintering The laser sintering process etc. which repeat alternately are mentioned. Here, in the case where the cylinder block body 60 is manufactured by casting or resin molding, there are merits described below.

First, when manufacturing a member by casting, volume contraction 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 easily occur. On the other hand, in the method of manufacturing an internal combustion engine according to the present embodiment, a separately manufactured connection is made as compared with the conventional method of manufacturing an internal combustion engine in which a cylinder block is formed by casting a cylinder liner with aluminum alloy or the like. The internal combustion engine 100 is manufactured by mechanically fitting the cylinder 10 and the cylinder block body 60. Therefore, the volume of the cylinder block body 60 can be made much smaller than the volume of the cylinder block of the conventional internal combustion engine. Therefore, in the case of manufacturing the cylinder block body 60 by casting, it is easy to suppress the occurrence of defects such as void caused by volume contraction. In addition to this, various measures for suppressing these defects (for example, making the wall thickness of a member manufactured by casting as constant as possible) as compared with the case of casting a cylinder block of a conventional internal combustion engine It does not have to be adopted positively. Therefore, it is possible to further increase the design freedom regarding the shape, structure, and casting process of the cylinder block body 60. For example, when a coolant jacket is provided to the cylinder block body 60 as compared with the coolant jacket provided to the cylinder block of the 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 In the case where the coolant jacket is provided between the outer surface 10S and the outer circumferential surface 10S, it is extremely easy to form a coolant jacket having a shallower depth from the other end side. These points are substantially the same as in the case of manufacturing the cylinder block main body 60 by resin molding in which volume contraction occurs in the process of cooling the molten resin material injected or injected into the mold.

In the method of manufacturing the internal combustion engine according to the present embodiment, the step of assembling various parts such as the cylinder head after the connecting cylinder 10 is attached to the cylinder block main body 60 and the inner periphery of the cylinder bore 20 A sliding surface forming process for forming a sliding surface by finishing such as honing, lapping and dimple processing, or a coolant passage between two cylinder bores 20 adjacent to each other in the connecting cylinder 10. Various processes, such as a process to form, can be suitably implemented if needed.

Here, in the present specification, the “sliding surface” refers to a piston ring or a contact slide mounted on a piston or a groove provided on an outer peripheral surface of the piston when the completed internal combustion engine 100 is operated. It means a moving face. Then, in the manufacturing process of the internal combustion engine 100 of the present embodiment, after the formation of the “sliding surface” is completed, further finishing is not performed on the “sliding surface”. The “sliding surface” is a surface that slides in contact with the piston or a piston ring mounted in a 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 the purpose. For example, in the case of (a) finish processing mainly aiming to correct deformation of the cylinder bore 20 or (b) finish processing mainly aiming to adjust the thickness of the cylinder liner 40 or the film thickness of the film 52 Accompanyingly, the sliding surface may be formed incidentally and inevitably. However, it is preferable that the sliding surface is a surface finished for the main purpose of improving and improving seizure resistance and suppressing oil consumption.

The “sliding surface” may be formed by performing the processing only once on the inner peripheral surface of the cylinder bore 20, or may be formed by performing the processing multiple times. In the case where the “sliding surface” is formed by carrying out a plurality of processings, the “sliding surface” means only the surface formed after the final processing of the final processing, and The process of performing the finishing process is referred to as "sliding surface forming process". In addition, the process of carrying out the processing other than the final round of finishing (the first processing to the final -1st processing) is referred to as a "roughly processed surface forming step".

The surface form of the "sliding surface" varies depending on the finishing method, and is not particularly limited. For example, with respect to the surface form, cross hatches (fine grid lines or grooves or oblique parallel lines) Surface, etc., and the surface roughness can be, for example, about 0.1 .mu.m to 0.8 .mu.m in arithmetic average roughness Ra.

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 any timing in the manufacturing process of the internal combustion engine 100. The sliding surface forming step is performed before the fitting step, or (II) the sliding surface forming step is performed after the fitting step. In the processes (I) and (II) described above, another process may be performed between the fitting process and the sliding surface forming process, as necessary.

(I) As a case where a sliding face formation process is implemented before a fitting process, the following three modes are mentioned, for example. First, when the connecting cylinder 10 is the first connecting cylinder 10A, (Ia) a sliding surface forming step of forming a sliding surface by finish working the inner peripheral surface 40B of the cylinder liner 40 A slide that forms a sliding surface by finishing the surface of the coating after performing a coating forming step of forming a coating on the inner circumferential surface 40B of the cylinder liner 40 or performed only before or (Ib) The dynamic surface forming process can be performed, and the sliding surface forming process can be performed only before the fitting process. Further, when the connecting cylinder 10 is the second connecting cylinder 10B, (Ic) by finishing the surface 52B of the coating 52 covering the inner circumferential surface 50B provided with the cylinder bore 20 of the connecting cylinder main body 50 The sliding surface forming process for forming the sliding surface can be performed only before the fitting process.

Here, when the sliding surface forming process is carried out before (I) the fitting process, it is preferable to carry out the fitting process by a fitting method other than tight fitting, specifically, the loose fitting Or it is more preferable to carry out by middle fitting. When the fitting process is performed by close fitting, the cylinder bore 20 of the connecting cylinder 10 is easily deformed, and as a result, airtightness between the piston and the sliding surface of the cylinder bore 20 is easily generated. This is because, after the fitting process, there is also an increase in the possibility that the sliding surface forming process needs to be performed again to also correct the deformation of the cylinder bore 20. In order to prevent such problems more reliably, it is particularly preferable to carry out the fitting step by loose fitting.

Moreover, as a case where a sliding face formation process is implemented after (II) fitting process, the following three aspects are mentioned, for example. First, when the connecting cylinder 10 is the first connecting cylinder 10A, (IIa) a sliding surface forming step of forming a sliding surface by finish working the inner peripheral surface 40B of the cylinder liner 40 After performing a film forming step of forming a film on the inner circumferential surface 40B of the cylinder liner 40 or implemented only after (IIb), the sliding surface is formed by finishing the surface of the film. The dynamic surface forming process can be performed, and the sliding surface forming process can be performed only after the fitting process. When the connecting cylinder 10 is the second connecting cylinder 10B, (IIc) by finishing the surface 52B of the coating 52 covering the inner peripheral surface 50B provided with the cylinder bore 20 of the connecting cylinder main body 50 The sliding surface forming process for forming the sliding surface can be performed only after the fitting process.

Here, when the sliding surface is formed by carrying out machining a plurality of times with respect to the inner peripheral surface of the cylinder bore 20, the roughing surface forming step may be performed before the fitting step, It may be carried out after the fitting process, and a part may be carried out before the fitting process and the rest may be carried out after the fitting process.

In the conventional general internal combustion engine in which the cylinder block is formed by casting the cylinder liner, the sliding surface forming step is performed after the cylinder block is formed by casting the cylinder liner. . For this reason, it is necessary to inspect the sliding surface after carrying out the sliding surface forming process and discard the entire cylinder block cast in the cylinder liner if the inspection result is judged to be a defect. .

On the other hand, when performing a sliding surface formation process before (I) fitting process, a sliding surface formation process will be implemented in the state of the connection cylinder 10 single-piece | unit. For this reason, after the sliding surface forming process is performed, the sliding surface is inspected, and when the inspection result is determined to be defective, only the connecting cylinder 10 may be disposed of. Therefore, even if defective defects occur, waste loss in the manufacturing process can be further reduced.

In the case where the sliding surface forming process is performed before (I) the fitting process, the sliding surface forming process may be performed on the connecting cylinder 10 alone, but the connecting cylinder 10 may be a cylinder block. The sliding surface forming step may be carried out in a state of being assembled to a jig simulating the main body 60 and the cylinder head. When the cylinder head is further assembled to the internal combustion engine 100 in a state where 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. For this reason, when performing a sliding face formation process using a jig in consideration of such a modification, it becomes easy to raise processing accuracy of a sliding face more.

Moreover, when performing a sliding face formation process using a jig | tool, it is preferable to carry out in the state which heated at least the connection cylinder 10, and it is more preferable to carry out in the state which heated the connection cylinder 10 and a jig | tool . As a result, it is possible to create an optimal sliding surface shape while keeping the temperature close to the temperature of the member at the time of operation. The temperature of the member to be heated in this case is particularly preferably as close as possible to the average temperature during operation of the internal combustion engine 100. The heating method is not particularly limited. For example, a method of carrying out the sliding surface forming step in a state where warm water (for example, warm water of 30 ° to 95 °) is flowed through the coolant jacket can be mentioned. The coolant jacket referred to here includes (i) a coolant jacket formed in the connecting cylinder 10, and (ii) an outer peripheral surface of the connecting cylinder 10 and an inner peripheral surface of a jig imitating the cylinder block main body 60. Or (iii) a (simulated) coolant jacket formed in a jig imitating the cylinder block body 60, and the like.

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

Also, 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 fluid passage forming step is performed to form a coolant fluid passage between two adjacent cylinder bores 20 of the connecting cylinder 10. It is preferable to do. In this case, the coolant passage forming step may be performed after the fitting step, but is more preferably performed before the fitting step. In any case, another process may be performed between the coolant passage forming process and the fitting process, as needed. In the coolant passage forming step, the coolant passage can be formed using various processing means such as a water jet, a laser, an end mill, a cutter, etc., in addition to generally used drills. .

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

Therefore, when performing a cooling design around the cylinder bore 20, it is easy to realize a more ideal design. For example, it is also possible to form a coolant passage which can not normally be achieved in the cases shown in the above (i) and (ii), that is, to form a coolant passage extending parallel to the end face of the connecting cylinder 10 on the cylinder head side. It becomes possible. Further, the cross-sectional shape of the coolant passage in a 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). Various shapes can be selected other than the coolant passage 30A (30). For example, it has a slit-like cross-sectional shape in which the ratio (Lz / Lx) of the maximum width Lz in the direction (Z direction) parallel to the center line C to the maximum width Lx in the alignment direction (X direction) of the cylinder bores 20 is larger than one. A coolant passage can be formed. The ratio (Lz / Lx) is, for example, preferably 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.

As the coolant passage 30 having such a slit-like cross-sectional shape, (a) for a coolant having an opening 34 continuing in the Y direction also on the end face 36 on the other end side (Z1 side) of the connecting cylinder 10 Passage 30B (30) (FIG. 14 (B)) or (b) inner side (one end side (Z2 side)) than the end face of the other end side (Z1 side, the side where the cylinder head is disposed) of the connecting cylinder 10 The coolant passage 30C (30) (FIG. 14 (C)) provided in FIG. However, the coolant passage 30C having a slit-like cross-sectional shape as illustrated in FIG. 14C is (a) inside the end surface 36 on the other end side (Z1 side) of the connecting cylinder 10 (one end side (Z2 By providing it on the side), it is possible to further increase the degree of freedom in the cooling design around the cylinder bore 20. When the coolant passage 30C having a slit-like cross-sectional shape as illustrated in FIG. 14C is formed, it is preferable to carry out the coolant passage forming step at least before the fitting step. 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 and after the fitting step, it is discarded as compared with the case shown in the above (ii). The object of disposal may be only the connecting cylinder 10. For this reason, it is possible to reduce waste loss due to processing errors.

The coolant passage 30 may be formed between two cylinder bores 20 adjacent to each other. However, in the first connecting cylinder 10A, the space between the outer peripheral surfaces 40A of the two cylinder liners 40 normally adjacent to each other is generally used. Between the outer peripheral side surfaces 52A of the coatings 52 which are formed in the region (region M1 shown in FIGS. 3 and 14) and which normally form the inner peripheral surface 20B of the two adjacent cylinder bores 20 in the second connecting cylinder 10B. (Area M2 shown in FIG. 5).

<Internal combustion engine, connected cylinder and cylinder block body>
Next, the internal combustion engine 100 manufactured by the method of manufacturing an internal combustion engine according to the present embodiment, and more preferable shapes and structures of the connecting cylinder 10 and the cylinder block main body 60 used for the same will be described below. An internal combustion engine 100 manufactured by the method of manufacturing an internal combustion engine according to this embodiment includes at least a connecting cylinder 10 and a cylinder block body 60 as illustrated in FIGS. 7 and 8, and the connecting cylinder 10 is a cylinder block The hollow portion 64 of the main body 60 is detachably fitted.

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 (inner than 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 than the inner peripheral surface 64S of the hollow portion 64) It can be provided in any of. However, in the case shown in the above (i), the connecting cylinder 10 is provided with a coolant jacket, so the structure of the connecting cylinder 10 is complicated, and in the case shown in the above (iii) As a result, the structure of the cylinder block body 60 is complicated. For this reason, it is preferable that the coolant jacket be provided between the connecting cylinder 10 and the cylinder block body 60. Moreover, it is preferable not to provide a cooling fluid jacket in the connecting cylinder 10, since the manufacturing efficiency tends to be reduced due to the complexity of the structure.

On the other hand, in the case shown in the above (ii), the internal combustion engine 100 can be compared to the conventional internal combustion engine in which the cylinder block including the coolant jacket is formed in the cylinder block by casting the cylinder liner. It is not necessary to use a mold of complicated shape in manufacturing. For this reason, 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 closer to an ideal state so that the temperature distribution on the sliding surface of the cylinder bore 20 is in a desired state. Accordingly, a coolant jacket spacer may be additionally disposed within the coolant jacket. Also in the case shown in (ii) above, either the first embodiment in which the coolant jacket spacer is disposed in the coolant jacket or the second embodiment in which the coolant jacket spacer is not disposed in the coolant jacket is selected. Although possible, the second aspect is more preferable. The reason 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. Further, since the connecting cylinder 10 and the cylinder block body 60 are separate and independent members, the degree of freedom in the shape design of both members is extremely high. Therefore, the design freedom of the shape and depth of the coolant jacket is also extremely high. Therefore, even in the second embodiment, it is extremely easy to bring the flow of the coolant in the coolant jacket close to an ideal state so that the temperature distribution on the sliding surface of the cylinder bore 20 is in a desired state. Further, the reduction in the number of parts constituting the internal combustion engine 100 and the simplification of the structure of the internal combustion engine 100 can also be realized.

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

In any of the above cases (i) to (iii), the depth D (the length in the Z direction) of the coolant jacket 70 is not particularly limited and may be appropriately selected according to the design specification of the internal combustion engine 100. Based on the total length L of the connecting cylinder 10 in the direction of the center line C of each cylinder bore 20 provided in the cylinder 10, for example, the depth D is in 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 a specification for selectively and intensively cooling a portion in the vicinity of the cylinder head side of the cylinder bore 20, the depth D is in the range of 1/6 to 1/2 times the total length L, It may be in the range of 1/6 times to 1/3 times, or in the range of 1/6 times to 1/4 times. Among the above (i) to (iii), (ii) is most preferable from the viewpoint of easy formation of the shallow coolant jacket 70 having a depth D of 1/2 or less of the total length L. Further, when it is desired to bring the flow of the coolant in the coolant jacket 70 closer to a more ideal state without arranging the coolant jacket spacer in the coolant jacket 70, the depth D is 1/2 times the total length L. The formation of the following shallow coolant jacket 70 is preferred.

The inner peripheral surface 64S of the fitting portion 64J and the inner peripheral surface 64S of the fitting portion 64J are provided so that the coolant (water and the like) in the coolant jacket 70 does not leak to the crank chamber 62 side. A seal member such as an O-ring, for example, is disposed between the opposing outer peripheral surface 10S of the connecting cylinder 10. At least one surface selected from the outer circumferential surface 10S of the connecting cylinder 10 facing the inner circumferential surface 64S of the fitting portion 64J and the inner circumferential surface 64S of the fitting portion 64J may be circumferential as necessary. A groove may be provided which is continuous in the direction, and the seal member may be attached to the groove.

Further, in order to improve the strength and the deformation of the cylinder head side of the cylinder bore 20 and to suppress the deformation, and to improve the reliability of the internal combustion engine 100 at high supercharging, (a1) the other end side of the outer peripheral surface 10S of the connecting cylinder 10 A protrusion may be provided on at least a part of the outer peripheral surface 10S, and the tip of the protrusion may be in 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. From the same point of view, a protrusion 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 (a2) 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 body 60. A fixing member 80 may be provided to fix the connecting cylinder 10 and the cylinder block body 60 to each other. From the viewpoint of easier manufacture of the connecting cylinder 10, it is more desirable to use the fixing member 80 than providing the projecting 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 the above (a1) and (a2), when the fitting portion is formed by the portion on the other end side of the connecting cylinder 10 and the portion on the other end side of the cylinder block main body, the fitting of the fitting portion The method may be any fitting method selected from loose fit, middle fit and tight fit. Further, as illustrated in (b), a first fitting portion is formed by the portion on the other end side of the connecting cylinder 10 and the fixing member 80, and the portion on the other end side of the cylinder block main body 60 and the fixing member 80 In the case where the second fitting portion is formed in the second fitting portion, the fitting method of the first fitting portion and the second fitting portion is any fitting selected from a loose fit, an intermediate fit and a tight fit. May be used. However, from the viewpoint of suppressing the deformation of the cylinder bore 20 at the time of assembly of the internal combustion engine 100, a loose fit or an intermediate fit is preferable, and a loose fit is particularly preferable. Such a fitting method is particularly suitable when employing a process in which a sliding surface forming step is performed prior to the (I) fitting step in assembling the internal combustion engine 100.

When the fixing member 80 is used, the outer peripheral surface 10S on the other end side of the connecting cylinder 10 is as illustrated in FIG. 1, FIG. 2, FIG. 4 and FIG. 8 so that the fixing member 80 does not shift from the 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 in the outer peripheral surface 10S of the connecting cylinder 10 as illustrated in FIGS. The groove 66 may be provided at the position where In this case, one end of the fixing member 80 is fitted in the groove 12 and the other end is fitted in the groove 66, so that 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 on the The groove 12 may be formed in advance in the connecting cylinder 10, and the groove 66 may also be formed in the cylinder block body 60 in advance. However, it is preferable to form the

grooves

12, 66 after the coupling cylinder 10 in which the grooves 12 are not formed and the cylinder block body 60 in which the grooves 66 are not formed.

In the example shown in FIG. 8, the cross-sectional shape of the fixing member 80 is rectangular, and the interface (first interface) between the fixing member 80 and the connecting cylinder 10, and the fixing member 80 and the cylinder block main body 60 All of the interfaces (second interfaces) are parallel to the center line C of the cylinder bore 20. Therefore, even when fixing member 80 is disposed between coupling cylinder 10 and cylinder block body 60 by close fitting during assembly of internal combustion engine 100, the piston is near the top dead center of the piston when internal combustion engine 100 is in operation. When the vicinity of the other end side (Z1 side) of the connecting cylinder 10 is thermally expanded, the gap between the first interface and the second interface may be lost. 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 dimension is 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-described 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 as it goes 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 away from the center line C of the cylinder bore 20 as it goes from one end side (Z2 side) to the other end side (Z1 side) of the cylinder block main body 60. For this reason, when the vicinity of the other end side (Z1 side) of the connecting cylinder 10 which is near the top dead center of the piston is thermally expanded during operation of the internal combustion engine 100, the pressure applied from the connecting cylinder 10 side to the fixing member 80 side The pressure is easily relieved by the fixing member 80 sliding to the other end side (Z1 side).

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

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

On the other hand, connecting cylinder 10 and cylinder block main body 60 have both the excellent maintainability, the excellent recyclability, and the high degree of freedom of design of internal combustion engine 100 manufactured using them, and also have a shape that is easy to manufacture It is preferable to further have a structure. However, the connecting cylinder 10 and the cylinder block body 60 are used to manufacture the internal combustion engine 100 by combining the two members. Therefore, even if the shape and structure of the connecting cylinder 10 are determined in consideration of only 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 is complicated and the cylinder block main body 60 The productivity of the internal combustion engine 100 may be reduced, or the productivity of the internal combustion engine 100 may be reduced. Moreover, this point is the same also when determining the shape and structure of the cylinder block main body 60 in consideration of only the manufacturability of the cylinder block main body 60. Therefore, in view of these points, the inventors have found that the shape and structure described below are preferable 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, with regard to the first connecting cylinder 10A, two or more cylinder liners 40 and a cross-sectional structure (YZ cross-sectional structure) shown in FIG. 1 and FIG. And a connecting portion 42 that connects two or more cylinder liners 40 to each other, and has a continuous 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 based on 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 central portion Between the first region 10S1 and the second region 10S2, which is larger than the outer diameter D2 based on the center line C of each cylinder liner 40 in the outer peripheral surface (second region 10S2) near the crank chamber side; Preferably, the step 14 is formed in parallel with and continuous with the outer peripheral direction.

In addition, in the second connection cylinder 10B, as illustrated in FIG. 10 illustrating the cross-sectional structure (YZ cross-sectional structure) between the symbols XX illustrated in FIG. 5, a connection in which two or more cylinder bores 20 are provided. It has a continuous annular outer peripheral shape including a cylinder body 50 and a coating 52 covering the inner circumferential surface 50B of the connecting cylinder body 50 provided with the cylinder bore 20, and 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 based on 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 Between the first region 10S1 and the second region 10S2, which is larger than the outer diameter D2 based on the center line C of each cylinder bore 20 in the outer peripheral surface (second region 10S2) near the chamber side, It is preferable that a step 14 parallel and continuous to the outer peripheral direction be 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.

Furthermore, in the cylinder block main body 60, it is preferable that the opening shape of the hollow portion 64 be a continuous annular shape corresponding to the outer peripheral shape of the connecting cylinder 10 illustrated in FIGS. Specifically, as illustrated in FIG. 6 and FIG. 8, on the inner circumferential surface 64S of the hollow portion 64, a first step 68A continuous in the circumferential direction and a first step 68A continuous in the circumferential direction are provided. The opening width of the hollow portion 64 at the inner peripheral surface 64S1 at the other end side (cylinder head side) of the first step 68A, having a second step 68B provided on one end side (crank chamber side) W1, an opening width W2 of the hollow portion 64 in the inner peripheral surface 64S2 on one end side (crank chamber side) of the first step 68A and the other end side (cylinder head side) of the second step 68B, and a second step It is preferable that the opening width W3 of the hollow portion 64 on the inner circumferential surface 64S3 on one end side (crank chamber side) of the 68B satisfy 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 short 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 short direction (Y direction) and the longitudinal direction (X direction). Note that the opening widths W1sm, W2sm, W3sm illustrated in FIG. 8 mean the maximum opening width in the short side direction (Y direction) of the opening shape of the hollow portion 64, and for the opening widths W1, W2, 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, in 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, the connecting cylinder 10 having the step 14 provided on the outer peripheral surface 10S is fitted. In this case, 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 in the center line C direction. . 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 (the first region 10S1 of the connecting cylinder 10) are in direct contact or in intimate contact via the seal member. At the same time, the inner peripheral surface 64S3 of the cylinder block main body 60 and the outer peripheral surface 10S (the second region 10S2 of the connecting cylinder 10) are in direct contact or in intimate contact via the seal member. That is, in the outer peripheral surface 10S of the connecting cylinder 10, the portion on the second region 10S2 side of the first region 10S1 and the second region 10S2 form a fitting portion corresponding to the fitting portion 64J of the cylinder block main body 60 Do. For this reason, the coolant jacket 70 formed between the inner peripheral surface 64S1 of the cylinder block main body 60 and the outer peripheral surface 10S of the connecting cylinder 10 (the first region 10S1) on the cylinder head side than the first step 68A. The coolant inside can be prevented from leaking to the crank chamber 62 side.

Further, for the volume of the coolant jacket 70 which controls the cooling characteristics in the cylinder bore 20 and in the vicinity of the cylinder bore 20 and the formation position of the coolant jacket 70 in the center line C direction, for example, This 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. And the change of the dimensional shape of the cylinder block main body 60 shown to said (1) and (2) is very easy also when the cylinder block main body 60 is manufactured by casting or resin molding. Even when the cylinder block body 60 is manufactured by casting or resin molding in which defects due to volume contraction easily occur, the cylinder block body 60 has a volume capacity higher than that of a conventional cylinder block formed by casting a cylinder liner. Is so small that these defects are less likely to occur.

The step 14 provided at the 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 surface on the side of the crank chamber 62 in the direction of the center line C of the connecting cylinder 10 is the reference position (position 0) and the end surface on the cylinder head side is the position L, the step 14 exceeds 0 and is 1⁄2L or less It is preferable to provide in the range, more preferably in the range of 1/6 L to 3/7 L, and still more preferably in the range of 1/6 L to 1/3 L. When the step 14 is provided at a position exceeding 1/2 L, the first step 68A provided on the cylinder block main body 60 side has to be provided at a position closer to the cylinder head side. Therefore, the range in which the first step 68A is provided becomes narrower in the direction of the center line C, and as a result, the depth D of the coolant jacket 70 is made deeper by design change in accordance with the required specification of the internal combustion engine 100. The margin that can be made shallower is smaller.

In addition, it is preferable that the outer peripheral shape of the connecting cylinder 10 is basically a simple shape provided with a step 14 which divides the outer peripheral surface 10S into the first region 10S1 and the second region 10S2, and as necessary, A groove 12 for fitting the fixing member 80 or a groove for mounting the sealing member may be provided.

On the other hand, the outer peripheral surface 10S of the connecting cylinder 10 can be provided with a projecting portion which protrudes from the outer peripheral surface 10S if necessary, and the outer peripheral surface 10S of the connecting cylinder 10 has a first region 10S1 and a second region. Even if it is any of 10S2, it is not necessary to provide a protrusion part.

When the projecting portion is not provided on the outer circumferential surface 10S, there are advantages described below. That is, when the projecting portion such as a flange is provided on the outer peripheral surface 10S, the projecting portion is easily broken when the connecting cylinder 10 is hit against another member due to carelessness or the like when handling or storing the connecting cylinder 10. Become. However, such a breakage can be suppressed if the protruding portion is not provided on the outer circumferential surface 10S.

In addition to this, when the outer circumferential surface 10S is provided with the projecting portion, the outer circumferential surface when manufacturing the connecting portion 42 of the first connecting cylinder 10A or the connecting cylinder main portion 50 of the second connecting cylinder 10B by casting. When the projecting portion is provided in 10S, the shape of the mold is slightly complicated and the manufacturability is somewhat reduced. In the case where the first region 10S1 is provided with a protrusion, the first step 68A in the direction of the (1) maximum opening width W1sm of the cylinder block main body 60 and (2) the center line C direction is appropriately reviewed. It becomes more difficult to redesign the volume 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 projecting portion is not provided on the outer circumferential surface 10S.

On the other hand, although the merit mentioned above is lost, cooling control of internal combustion engine 100 can also be performed more precisely by providing a projection part in the 1st field 10S1 of peripheral face 10S. In this case, as in the first connecting cylinder 10A2 (10A, 10) illustrated in FIG. 11, in the first region 10S1, the region of the first region 10S1 is the cylinder head side (Z1 direction side) and the crank chamber side It is preferable to provide a ridge portion 16A (16) to be divided into the region in the Z2 direction). 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 form of connected rings. The first connecting cylinder 10A2 shown in FIG. 11 is a member having the same structure as that of 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 that divides 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 flange portion The coolant jacket 70 has a structure divided in the direction of the center line C of the cylinder liner 40 or the cylinder bore 20 by 16A. FIGS. 12 and 13 are schematic cross-sectional views showing an example of an internal combustion engine 100 provided with a connecting cylinder 10 in which a flange portion 16A is 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 a first connecting cylinder 10A2 having a 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 (i) replaces the first connecting cylinder 10A1 shown in FIG. 8 with a first connecting cylinder 10A2 having a flange portion 16A shown in FIG. And (ii) the cylinder block main body 60A shown in FIG. 8 is replaced by a cylinder block main body 60B having a third step 68C continuous in the circumferential direction 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). The inner circumferential surface 64S1 has the third step 68C as a boundary line, and the cylinder head side area 64S1A on the cylinder head side (Z1 direction side) of the third step 68C and the crank chamber than the third step 68C. It is divided into two regions of the side (Z2 direction side) of the crankcase side region 64S1B. Further, the crank chamber side region 64S1B is positioned relatively closer to the inner circumferential side than the cylinder head side region 64S1A. In the Y direction, the cylinder head side area 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 area 64S1A shown in FIG. 13 is positioned on the outer peripheral side relative to the crank chamber side area 64S1B, the cylinder head side area 64S1A is flush with the inner peripheral surface 64S1 of the cylinder block main body 60A shown in FIG. Need not be provided.

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 main bodies 60A and 60B. The coolant jacket 70 formed on the cylinder head is divided by the flange portion 16A into a portion on the cylinder head side (cylinder head side coolant jacket 70A) and a portion on the crank chamber side (crank chamber side coolant jacket 70B) . Therefore, as compared with the internal combustion engine 100A shown in FIG. 8, the

internal combustion engines

100B, 100C shown in FIG. 12 and FIG. The jacket 70A and the crankcase side coolant jacket 70B can be individually controlled. Therefore, in the

internal combustion engines

100B and 100C, it is extremely easy to individually perform temperature control of the portion near the cylinder head and the portion near the crank chamber among the portions of the cylinder bore 20 surrounded by the coolant jacket 70. It is. And, if such characteristics are used, various merits as exemplified in the following (a) to (c) can be easily realized.

(A) Of the portions of the cylinder bore 20 surrounded by the coolant jacket 70, by controlling the temperatures of the portion near the cylinder head and the portion near the crank chamber, the

internal combustion engines

100B and 100C are in operation. The cylindricity of the cylinder bore 20 is improved. For example, the temperature of the cylinder bore 20 in the portion near the cylinder head side is lower than that in the case where the coolant jacket 70 is divided by the flange portion 16A, and the temperature of the cylinder bore 20 in the portion near the crank chamber is higher. 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 to advance the lead angle. Further, by raising the temperature of the cylinder bore 20 at the portion near the crank chamber side, it is possible to easily reduce the friction and improve the warm-up performance. 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 consumption.
(B) With respect to the portion of the cylinder bore 20 surrounded by the coolant jacket 70, the cooling efficiency of the portion near the cylinder head is relatively improved with respect to the portion near the crank chamber side. The temperature of the inner wall surface (sliding surface) of the cylinder bore 20 is lowered to improve the knock resistance and improve the fuel consumption.
(C) The flow rate, flow rate, and water temperature of the coolant in the cylinder head side coolant jacket 70A, and the crankcase side coolant so that optimum output, fuel efficiency, etc. can be obtained according to the operating conditions of the

internal combustion engines

100B and 100C. The flow rate, the flow rate and the water temperature of the cooling fluid 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 16A contacts the cylinder head side area 64S1A of the inner peripheral surface 64S1 of the cylinder block main body 60A, and the crank chamber side (Z2 direction side) of the flange 16A. The portion on the top surface side of the side surface is in contact with the stepped surface portion of the third step 68C. In this case, it is preferable to provide a seal member such as an O-ring at the interface between the top surface of the flange 16A and the inner circumferential surface 64S1 to completely seal the interface between the flange 16A and the inner circumferential surface 64S1. For example, the O-ring is provided with a groove along the circumferential direction of the top surface of the flange portion 16A, and is attached to this groove, or in the case of the internal combustion engine 100C shown in FIG. A groove may be provided along the circumferential direction of the portion, and the groove may be mounted and used.

In addition, if the controllability at the time of individually controlling the flow rate, flow rate and water temperature of the coolant between cylinder head side coolant jacket 70A and crankcase side coolant jacket 70B is not significantly impaired, the seal is provided. The members may be omitted, or some gap may be formed between the top surface of the collar portion 16A and the inner peripheral surface 64S1. In addition, in part of the circumferential direction of the collar portion 16A, if necessary, there is provided a flow path which penetrates in the direction of the center line C and connects the cylinder head side coolant jacket 70A and the crank chamber side coolant jacket 70B. It is also good.

In addition, if the flange portion 16A can divide the cooling fluid jacket 70 into the cylinder head side cooling fluid jacket 70A and the crankcase side cooling fluid jacket 70B, any one of the first region 10S1 with respect to the center line C direction It can be provided at the position of However, assuming that the end on the cylinder head side of the first region 10S1 in the center line C direction is the reference position 0 and the total length of the first region 10S1 in the center line C direction is L1, the ridge portion 16A is 0.2 × L1. It is preferable to provide in the range of about 0.5 × L1. Similarly, assuming that the end on the cylinder head side of the connecting cylinder 10 in the center line C direction is 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 in the range of about 0.37 × L.

Further, the flange portion 16 provided on the outer circumferential surface 10S may be formed continuously along the centerline 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 connection cylinder shown in FIG. In the first connecting cylinder 10A3 (10A, 10) shown in FIG. 15, the ridge portion 16B (16) formed continuously along the center line C direction on the outer peripheral surface 10S at both ends in the alignment direction of the cylinder bores 20. 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, although the collar part 16B is provided in the outer peripheral surface 10S of the both end side of the alignment direction of the cylinder bore 20, you may be provided in positions other than this.

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 surface 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 guide grooves corresponding to the flange portion 16B. Is provided. In addition to the inner circumferential surfaces 64S2 and 64S3, a guide groove corresponding to the ridge 16B may be provided on the inner circumferential surface 64S1 in accordance with the height of the ridge 16B. That is, in the cylinder block body 60, a guide groove corresponding to the flange portion 16B is formed on at least a part or all of the inner peripheral surface 64S on both ends of the opening of the hollow portion 64 in the longitudinal direction (X direction). Is continuously formed from one end side (Z2 side) to the other end side (Z1 side). Therefore, the first connection cylinder 10A3 is stably fixed by the cylinder block main body 60 having the guide groove on the inner peripheral surface 64S by the flange portion 16B fitting with the guide groove. Be done.

In the example shown in FIG. 15, the flange portion 16B is continuously provided on the outer peripheral surface 10S 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 purpose of fixing the first connecting cylinder 10A3 more stably to the cylinder block main body 60, the inner circumferential surface 64S2 of the inner circumferential surface 64S of the hollow portion 64, In the outer peripheral surface 10S, the flange portion 16B is 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 the first connecting cylinder 10A4 (10A, 10) in which the flange portion 16B is provided on the outer peripheral surface 10S as described above.

When the flange portion 16B is provided mainly for dividing the coolant jacket 70, the flange 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 to the position from the step 14 closer to the other end side (Z1 side). FIG. 17 shows the first connecting cylinder 10A5 (10A, 10) in which the flange portion 16B is provided on the outer peripheral surface 10S as described above.

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

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 be a horizontally opposed engine. In this case, even if gravity acts on the first connection cylinder 10A4 in a direction substantially orthogonal to the center line C of the cylinder bore 20 in the horizontally opposed engine, the first connection cylinder 10A4 is inclined relative to the horizontal surface It can be surely suppressed. Therefore, the cylinder block body 60 is assembled also when assembling the internal combustion engine 100 in a state where the cylinder block body 60 provided with the guide groove on the inner circumferential surface 64S is placed horizontally (the Z direction substantially matches the horizontal direction). It is easy to position the first connecting cylinder 10A4 with respect to the

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 modified example of the cylinder block main body 60A shown in FIG. 6, except that a guide groove 69 is further provided to the cylinder block main body 60A. It is a member which has the same dimensional shape. As shown in FIG. 18, the guide groove 69 is provided on the inner circumferential surface 64S at both ends in the longitudinal direction (X direction) of the opening 64X of the hollow portion 64. Here, the guide groove 69 is provided on any of the inner circumferential surface 64S1, the inner circumferential surface 64S2, and the inner circumferential surface 64S3 so as to correspond to the flange portion 16B shown in FIG. However, the guide groove 69 may be omitted in the inner circumferential surface 64S1 according to the height of the flange portion 16B. Further, also in the case of using the first connecting cylinder 10A4 shown in FIG. 16, it is not necessary to provide the guide groove 69 in the inner peripheral surface 64S1.

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

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

Further, the flange portion 16 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 Among the above, the second portion (the flange portion 16B) may be provided to divide the portion constituting the side wall surface of the coolant jacket 70 in the outer circumferential direction. In the internal combustion engine 100 provided with the connecting cylinder 10 having the flange portion 16 as described above, the coolant jacket 70 can be divided in the direction of the center line C of the cylinder liner 40 or the cylinder bore 20 by the first portion. In addition to this, the coolant jacket 70 can be divided or divided in the circumferential direction by the second portion. 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 (ridge portion 16A) which is continuously formed along the outer peripheral direction and has an annular shape in which the arrangement position in the center line C direction is the same at any position in the outer peripheral direction; Connecting cylinder 10 provided in a first region 10S1 with a collar portion 16 having a linear second portion (ridge portion 16B) provided along a portion where the division boundary surface and the first region 10S1 intersect An internal combustion engine 100 using this can be illustrated. In this case, the coolant jacket 70 is divided by the first portion into a cylinder head side coolant jacket 70A and a crankcase side coolant jacket 70B. Furthermore, the cylinder head side coolant jacket 70A is divided into a portion on one side (Y1 direction side) of the division boundary surface and a portion on the other side (Y2 direction side) 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) of the division boundary surface and a portion on the other side (Y2 direction side). That is, the coolant jacket 70 is divided into four.

The internal combustion engine 100 has a structure in which the coupling 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 specific examples in FIGS. What is necessary is just to combine the connecting cylinder 10 and the cylinder block main body 60 which have the structure shown to the following (1) or (2) at least.
(1) A connecting cylinder 10 provided with a collar 16B (fixing collar) along the direction parallel to the center line C of each cylinder bore 20 provided in the connecting cylinder 10 on the outer peripheral surface 10S, and a hollow portion An internal combustion engine 100 having a cylinder block main body 60 provided with a guide groove 69 which is fitted to 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 (fixing flange) along the direction parallel to the penetration direction (Z direction) of the hollow portion 64 on the inner peripheral surface 64S of the hollow portion 64; An internal combustion engine 100 having a connecting cylinder 10 provided with a guide groove fitted on a collar (fixed collar) provided on an outer peripheral surface 10S of the cylinder 10 (provided on the cylinder block main body 60).

Here, it is preferable that the internal combustion engine 100 shown to said (1) and (2) has a structure as shown below.

That is, in the internal combustion engine 100 shown in the above (1), the connecting cylinder 10 at the both end sides in the arrangement direction (X direction) of the respective cylinder bores 20 provided in the connecting cylinder 10 with the flanges 16B (fixing flanges). The guide groove 69 is 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 preferred. Further, in the internal combustion engine 100 shown in the above (2), the flange portion (fixing flange portion) is 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. It is preferable that the guide groove is provided on the inner circumferential surface 64S of the second embodiment and the guide groove is provided on the outer circumferential surface 10S of the connecting cylinder 10 at both ends in the arrangement direction (X direction) of each cylinder bore 20 provided in the connecting cylinder 10. .

The above-mentioned structure in which the fixing flange portion and the guide groove are fitted on both end sides in the X direction is particularly preferable 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 body 60 at the time of assembly can be facilitated.

In the internal combustion engine 100 shown in the above (1) and (2), the coolant jacket can be provided at any position shown in the following (i) to (iii) but it is provided in the position shown in (ii) Is particularly preferred. When a 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 is The support / fixation tends to be unstable compared to the case where the coolant jacket is provided at the position shown in (i) or (iii). However, in the internal combustion engine 100 shown in the above (1) and (2) having a structure in which the fixing flange portion and the guide groove are fitted, the above-mentioned problem can be suppressed.
(I) Inside the connecting cylinder 10 (inner than 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 than 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 ridge portion (division ridge portion) for dividing the coolant jacket 70 into two or more parts is: 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 in which (a) the dividing collar portion is provided on the outer peripheral surface 10S of the connecting cylinder 10, an internal combustion engine 100B shown in FIG. 12, an internal combustion engine 100C shown in FIG. The internal combustion engine 100 which combined cylinder 10A3 and the cylinder block main body 60C shown in FIG. 18 is mentioned. In the internal combustion engine 100B shown in FIG. 12 and the internal combustion engine 100C shown in FIG. 13, the cooling fluid jacket 70 is divided into two parts (a cylinder head side cooling fluid jacket 70A and a crankcase side cooling fluid) 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 divided into two parts by the flange 16B (dividing ridge). 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. In addition, although the collar part 16B in the internal combustion engine 100 which combined 1st connection cylinder 10A3 shown in FIG. 15 and the cylinder block main body 60C shown in FIG. 18 is used as a collar for fixation, the collar part for divisions Also has the function of Thus, the fixing collar may also have the function of the dividing collar.

On the other hand, as a specific example in which (b) the dividing collar portion is provided on the inner peripheral surface 64S of the hollow portion 64 of the cylinder block main body 60,

internal combustion engines

100B and 100C shown in FIGS. In an internal combustion engine 100 in which one coupling cylinder 10A3 and a cylinder block main body 60C shown in FIG. 18 are combined, an internal combustion engine in which a collar (division collar) is provided not on the coupling cylinder 10 side but on the cylinder block main body 60 side. One hundred can be 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. In the connecting cylinder 10 which is formed but does not have the ridge portion 16 as illustrated in FIGS. 9 and 10, (1) a member having a shape corresponding to the annular collar portion 16A, (2) center line A member having a shape corresponding to a linear ridge 16B extending along a direction parallel to C, or (3) the above-described semi-annular or annular first portion (ridge 16A) and a linear second 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 (bar portion 16B).

The fitting method of the fitting part in which the collar part 16 and the cylinder block main body 60 fit is not particularly limited, and any fitting method selected from loose fit, middle fit and tight fit Although it is preferable, if it is desired to suppress the deformation of the cylinder bore 20, a loose fit or an intermediate fit is preferable, and a loose fit is more preferable.

Further, a flange portion (division flange portion) provided on the connection 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 flange portion 16A continuously formed along the outer peripheral direction of the connecting cylinder 10 or the inner peripheral direction of the hollow portion 64 of the cylinder block main body 60 instead of the flange portion 16A is continuously formed If the flange portion has no through hole, the cylinder head side coolant jacket 70A and the crank chamber side coolant jacket 70B do not communicate via the through hole. For this reason, the control of the liquid temperature, the flow rate, and the like of the coolant independently performed independently of each other by the cylinder head side coolant jacket 70A and the crank chamber side coolant jacket 70B can be performed more reliably. Note that “the width direction of the buttocks” means a direction parallel to the surface on which the buttocks are provided and orthogonal to the longitudinal direction of the buttocks, and in the case of the buttocks 16A shown in FIG. It means the length of the direction, and in the flange portion 16B shown in FIG. 15, it means the length of the outer circumferential direction (or the Y direction).

In addition, when the collar portion (dividing collar portion) has a through hole penetrating in the width direction of the collar portion, the collar portion is a closing member such as a plug or lid capable of closing the through hole in addition to the through hole It is preferable to have In this case, when the internal combustion engine 100 is in operation, it is preferable that the through hole is closed by a closing member such as a plug or a lid. For example, when internal combustion engine 100B illustrated in FIG. 12 has flange portion 16A having a through hole in a non-closed state when internal combustion engine 100 operates, the coolant is the cylinder head side coolant through this through hole. Since the jacket 70A and the crankcase side coolant jacket 70B can be moved back and forth, it becomes difficult to perform more precise cooling control. These points also apply to the case where the collar 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 internal combustion engine 100, for example, when 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, the portion excluding the cylinder liners is integrally formed by casting. Therefore, in the conventional internal combustion engine, as in the

internal combustion engines

100B and 100C shown in FIGS. 12 and 13, the coolant jacket 70 is divided into the cylinder head side coolant jacket 70A and the crankcase side coolant jacket 70B. It was impossible to realize the above structure (coolant jacket split structure) only by the casting process. Also, in order to realize the coolant jacket split structure after casting, it is necessary to construct a coolant jacket split structure within a coolant jacket having a narrow width at the opening on the cylinder head side. The productivity is extremely bad, 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 and The combination with the cylinder block body 60 can be extremely easily realized, and the mass productivity is also extremely excellent.

In the internal combustion engine 100 of the present embodiment, at least one fitting portion in which the connecting cylinder 10 and the cylinder block main body 60 fit may be provided. 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 is not limited to the first fitting portion (fitting portion 64J) positioned closest to one end side (Z2 side). A second fitting portion (for example, a fitting portion via the fixing member 80 illustrated in FIGS. 8, 12 and 13) located closest to the other end side (Z1 side), or one end side in the Z direction (Z2 Such as a third fitting portion (between the flange portion 16 and the cylinder block body 60 illustrated in FIGS. 12 and 13 etc.) positioned between the side) and the other end side (Z1 side) In some cases, two or more fitting portions may be provided in the Z direction.

As described above, when the internal combustion engine 100 of the present embodiment has two or more fitting parts in the Z direction, the fitting method in each fitting part may be the same or different. Moreover, the aspect illustrated below is mentioned as a combination of the suitable fitting system in each fitting part.

(In the case where the internal combustion engine 100 has the first, second and third fitting portions)
・ Combination example A1
First to third fitting parts: clearance fitting In this combination, it is extremely easy to suppress the deformation of the cylinder bore 20 in the entire Z direction.
・ Combination example A2
1st fitting part: middle fit, 2nd fitting part and 3rd fitting part: loose fitting In this combination, while it is very easy to suppress deformation of the cylinder bore 20 in the vicinity of the area where the piston reciprocates, The connecting cylinder 10 can be more stably fixed to the cylinder block body 60 as compared to the combination example A1.

(In the case where the internal combustion engine 100 has the first and third fitting portions)
・ Combination example B1
First fitting portion and third fitting portion: loose fitting 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: middle fit, third 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, compared to the combination example B1. The connecting cylinder 10 can be fixed to the cylinder block body 60 more stably.

(In the case where 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
1st fitting part: middle fit, 2nd fitting part: gap fitting It is extremely easy to suppress the deformation of the cylinder bore 20 in the vicinity of the region where the piston reciprocates, compared with the combination example C1. The connecting cylinder 10 can be fixed to the cylinder block body 60 more stably.

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

The internal combustion engine 100 according to the present embodiment is applicable to a large engine (for example, a large diesel engine for ships and / or a large engine whose displacement exceeds 30 L or 60 L). It becomes difficult to manufacture the connecting cylinder 10 and the cylinder block body 60 (in particular, the cylinder block body 60) corresponding to the amount or the size of the engine size. Therefore, 60 L or less is preferable, as for the displacement of the internal combustion engine 100 of this embodiment, 30 L or less is preferable, and 10 L or less is especially preferable. Further, for the same reason, it is preferable that the internal combustion engine 100 of the present embodiment is an internal combustion engine excluding the above-described large engine.

Further, the connection cylinder 10 of the present embodiment may be combined with members other than the cylinder block main body 60 to constitute an internal combustion engine. The structure of such an internal combustion engine is not particularly limited, and may be either liquid-cooled or air-cooled. For example, in the case of a large diesel engine for ships and / or a large engine whose displacement exceeds 30 L or 60 L, a cover surrounding the connecting cylinder 10 and the outer peripheral surface 10S of the connecting cylinder 10 near the cylinder head An internal combustion engine having a member can be provided. The cover member is fixed to the connecting cylinder 10 by a plurality of bolts. In this case, the cooling fluid is supplied to the cooling chamber formed between the outer circumferential surface 10S of the connecting cylinder 10 and the cover member. In such a large displacement internal combustion engine, although it is difficult to manufacture the cylinder block main body 60 having a large size and size according to the displacement by casting, it is difficult to manufacture due to problems such as blows. Since the size and volume are much smaller than the block body 60, manufacture is easy.

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 (part of outer peripheral surface 10S)
10ES: end face 12: groove 14:

step

16, 16A, 16B: ridge portion 20: cylinder bore 20B: inner

circumferential 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 area (part of inner peripheral surface 64S1)
64S1B: Crank chamber side area (part of the inner circumferential 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: crankcase side coolant jacket 80: (head Side) Fixing

members

100, 100A, 100B, 100C: Internal combustion engine

Claims

(1) a first connecting cylinder including two or more cylinder liners and a connecting portion connecting the two or more cylinder liners to each other;
(2) A second connection cylinder including a connection cylinder main body provided with two or more cylinder bores and a coating that covers the inner peripheral surface of the connection cylinder main body provided with the cylinder bore,
The crank chamber is formed on one end side of one of the connecting cylinders selected from the group consisting of: 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. A method of manufacturing an internal combustion engine, comprising: manufacturing an internal combustion engine through at least a fitting step of fitting the hollow portion of the cylinder block body.
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 loose fit, an intermediate fit and a tight fit.
The connection cylinder is the first connection cylinder,
3. The internal combustion engine according to claim 1, wherein a sliding surface forming step of forming a sliding surface by finishing the inner peripheral surface of the cylinder liner is performed only before the fitting step. How to make an organization.
The connection cylinder is the first connection 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 connection cylinder is the second connection cylinder,
A sliding surface forming step of forming a sliding surface by finishing the surface of the coating covering the inner peripheral surface provided with the cylinder bore of the connecting cylinder main body is carried out only before the fitting step. The method for manufacturing an internal combustion engine according to claim 1 or 2, characterized in that
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 loose 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 carried out by close fitting.
The sliding surface forming step is characterized in that the connecting cylinder is assembled to a jig simulating the cylinder block 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, wherein
9. A coolant passage forming step for forming a coolant passage between two adjacent cylinder bores of the connecting cylinder is performed at least before the fitting step. A method of manufacturing an internal combustion engine according to any one of the items.
The coolant passage is provided inside the end face of the connecting cylinder on which the cylinder head is disposed, and
10. The method for manufacturing an internal combustion engine according to claim 9, wherein a cross-sectional shape of the coolant passage in a plane parallel to a center line of each cylinder bore provided in the connection cylinder is a slit.
(1) a first connecting cylinder including two or more cylinder liners and a connecting portion connecting the two or more cylinder liners to each other;
(2) A second connection cylinder including a connection cylinder main body provided with two or more cylinder bores and a coating that covers the inner peripheral surface of the connection cylinder main body provided with the cylinder bore,
Any connected cylinder selected from the group consisting of
At least a cylinder block main body having a crank chamber formed at one end, a cylinder head assembled at the other end, and a hollow portion penetrating from the one end to the other end;
The internal combustion engine according to claim 1, wherein the connecting cylinder is detachably fitted to the hollow portion of the cylinder block body.
The internal combustion engine according to claim 11, wherein the connecting cylinder is fitted in the hollow portion of the cylinder block body in any fitting method selected from a loose fit and an intermediate fit. .
A coolant passage is provided between two adjacent cylinder bores of the connecting cylinder on the inner side of the end face of the connecting cylinder on which the cylinder head is disposed,
13. The internal combustion engine according to claim 11, wherein a cross-sectional shape of the coolant passage in a plane parallel to a center line of each cylinder bore provided in the connecting cylinder is a slit.
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 fitted to the fixing flange portion is provided on an inner peripheral surface of the hollow portion of the cylinder block main body. .
The fixing collar portion is provided on the outer peripheral surface of the connecting cylinder at both ends in the arrangement direction of the cylinder bores,
The internal combustion engine according to claim 14, wherein the guide groove is provided on the inner peripheral surface of the hollow portion of the cylinder block main body at both ends in the longitudinal direction of the opening of the hollow portion.
A collar for fixing is provided on an inner peripheral surface of the hollow portion of the cylinder block main body along a direction parallel to a penetrating direction of the hollow portion,
The internal combustion engine according to any one of claims 11 to 13, wherein a guide groove fitted to the fixing flange portion is provided on an outer peripheral surface of the connecting cylinder.
The fixing collar portion is provided on the inner peripheral surface of the hollow portion of the cylinder block main body at both ends in the longitudinal direction of the opening portion of the hollow portion,
The internal combustion engine according to claim 16, wherein the guide groove is provided on the outer peripheral surface of the connecting cylinder at both ends in the arrangement direction of each cylinder bore provided in the connecting cylinder.
The internal combustion engine according to claim 15 or 17, which is a horizontally opposed engine.
19. A liquid 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, according to any one of claims 11 to 18. Internal combustion engine.
A dividing ridge portion for dividing the coolant jacket into two or more portions is provided on at least one of the outer peripheral surface of the connecting cylinder and the inner peripheral surface of the hollow portion of the cylinder block main body. 20. The internal combustion engine of claim 19, wherein:
21. The internal combustion engine according to claim 20, wherein the dividing ridge portion does not have a through hole penetrating in a width direction of the dividing ridge portion.
21. The internal combustion engine according to claim 20, wherein the dividing collar portion has a through hole penetrating in the width direction of the dividing 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 during operation of the internal combustion engine.
The internal combustion engine according to any one of claims 20 to 23, wherein a coolant jacket spacer is not disposed in the coolant jacket.
The depth D of the coolant jacket is equal to or less than half 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. 20. The internal combustion engine of any one of 20 to 24.
The depth D of the coolant jacket is equal to or less than 1/2 times the total length L of the coolant jacket in a direction parallel to the center line of each cylinder bore provided in the connection cylinder, and the coolant jacket Internal combustion engine according to any one of claims 20 to 25, characterized in that no coolant jacket spacer is arranged therein.
A connecting cylinder comprising: two or more cylinder liners; and a connecting portion connecting the two or more cylinder liners to each other.
It has a continuous annular outer peripheral shape in which the bore diameter of each cylinder liner is expanded,
The outer diameter D1 based on the centerline 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 in the centerline direction of each cylinder liner is the outer periphery near the crankcase side. Greater than the outer diameter D2 relative to the centerline of each cylinder liner in the second region of the surface,
The connection cylinder according to claim 27, wherein a step parallel to and continuous with the outer peripheral direction is formed between the first area and the second area.
A connecting cylinder comprising: a connecting cylinder body provided with two or more cylinder bores; and a coating covering an inner peripheral surface of the connecting cylinder body provided with the cylinder bore.
A connecting cylinder body provided with two or more cylinder bores, and a coating covering an inner circumferential surface of the connecting cylinder body provided with the cylinder bore,
It has a continuous annular outer peripheral shape in which the bore diameter of each cylinder bore is expanded,
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 of the cylinder head side to the vicinity of the central portion in the center line direction of each cylinder bore is from the outer peripheral surface near the crank chamber side. Greater than the outer diameter D2 relative to the center line of each cylinder bore in the second region
The connection 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 connection cylinder according to any one of claims 27 to 30, wherein a collar portion is provided on the outer peripheral surface.
31. The connection according to claim 28 or 30, wherein the first area is provided with a flange portion for dividing the first area into an area on the cylinder head side and an area on the crank chamber side. Cylinder.
The connection cylinder according to claim 31 or 32, wherein the ridge portion does not have a through hole penetrating in a width direction of the ridge portion.
The connection cylinder according to claim 31 or 32, wherein the collar portion has a through hole penetrating in a width direction of the collar portion, and a closing member capable of closing the through hole.
A coolant passage is provided between two adjacent cylinder bores of the connecting cylinder on the inner side of the end face of the connecting cylinder on which the cylinder head is disposed,
35. The cross section of the coolant passage in a plane parallel to the center line of each cylinder bore provided in the connecting cylinder is in the form of a slit, according to any one of claims 27 to 34. Connection cylinder.