WO2017189489A1

WO2017189489A1 - Monoblock engine

Info

Publication number: WO2017189489A1
Application number: PCT/US2017/029260
Authority: WO
Inventors: James A. DODS; III John Jerl PURCELL; John Peter JONES; Paul Andrew Leggott; John R. Anderson; Graham DOWSON; Sudhir MANAGOLIKAR; Zbigniew G. Krawiec
Original assignee: Cummins Inc
Priority date: 2016-04-29
Filing date: 2017-04-25
Publication date: 2017-11-02

Abstract

A monoblock engine, comprising a cylinder head, a cylinder block positioned adjacent the cylinder head and comprising at least one cylinder bore, and an upper crank case positioned adjacent the cylinder block and comprising a portion of at least two main bearings, the portion having a first side and a second side, at least one of the first side and the second side having an indentation.

Description

MONOBLOCK ENGINE

TECHNICAL FIELD OF THE DISCLOSURE

[0001] The present disclosure relates to a monoblock engine including a cylinder head, a cylinder body, and an upper crank case, and more particularly, to a monoblock engine including indentations within main bearings of a crank case and cylinder bores of a cylinder body that allow machining of a monoblock engine including a cylinder head, a cylinder body, and an upper crank case as a single component.

BACKGROUND OF THE DISCLOSURE

[0002] There is a consistent desire to create a monoblock engine including as many engine components as possible in order to decrease weight and cost and increase reliability of the engine. Common engine designs use separate cylinder head and cylinder block components which creates a joint that is required to seal a high pressure. The more separate components an engine has the more joints that exist that must be adequately sealed to withstand high pressures that occur during engine operation and the less reliable the engine as a whole can be. Thus, it would be beneficial to have a monoblock engine comprising a cylinder head, a cylinder body, and a crank case as one integral component to reduce the number of joints within the engine and thus increase the reliability of the engine.

SUMMARY OF THE DISCLOSURE

[0003] In one embodiment of the present disclosure, a monoblock engine comprises a cylinder head, a cylinder block positioned adjacent the cylinder head and comprising at least one cylinder bore, and an upper crank case positioned adjacent the cylinder block and comprising a portion of at least two main bearings, the portion having a first side and a second side, at least one of the first side and the second side having an indentation.

[0004] In one aspect of the monoblock engine, the upper crank case comprises a portion of at least three main bearings, the at least three main bearings comprising an inner main bearing extending across an interior of the upper crank case and outer main bearings, the inner main bearing having an indentation on both the first side and the second side and the outer main bearings each having an indentation in one of the first side and the second side.

[0005] In another aspect of the monoblock engine, the one of the first side or the second side of the outer main bearings comprising the indentation faces inward toward the interior of the upper crank case.

[0006] In a further aspect of the monoblock engine, the cylinder block comprises four cylinder bores and the upper crank case comprises portions of at least five main bearings.

[0007] In another aspect of the monoblock engine, the at least one cylinder bore comprises a first end proximate the cylinder head, a second end spaced apart from the cylinder head and proximate the upper crank case, and at least two indentations disposed about the second end of the at least one cylinder bore.

[0008] In a further aspect of the monoblock engine, the upper crank case further comprises a bearing insert positioned within each main bearing, the bearing insert covering the at least one indentation.

[0009] In another aspect of the monoblock engine, the at least one indentation permits machining of the at least one cylinder bore when the cylinder head, the cylinder block, and the upper crank case are a single component.

[0010] In another aspect of the monoblock engine, the at least one indentation permits a piston of the cylinder bore to be disposed within the cylinder bore when the cylinder head, the cylinder block, and the upper crank case are a single component.

[0011] In a further aspect of the monoblock engine, the at least one indentation is rounded.

[0012] In another embodiment of the present disclosure, a monoblock engine comprises a cylinder head, a cylinder block positioned adjacent the cylinder head, the cylinder block comprising at least one cylinder bore, and an upper crank case positioned adjacent the cylinder head, wherein each cylinder bore comprises a first end proximate the cylinder head, a second end proximate the upper crank case, and at least two indentations disposed about the second end.

[0013] In one aspect of the monoblock engine, each cylinder bore comprises four indentations, the indentations being rounded.

[0014] In a further aspect of the monoblock engine, the at least one cylinder bore comprises a first pass through clearance and the at least one indentation cooperates with the cylinder bore to provide a second pass through clearance that is larger than the first pass through clearance.

[0015] In another aspect of the monoblock engine, the at least two indentations permit a machining device to access and machine out valve seat bores of at least two valves within the cylinder head when the cylinder head, the cylinder block, and the upper crank case are a single component.

[0016] In another aspect of the monoblock engine, the cylinder block comprises four cylinder bores.

[0017] In another aspect of the monoblock engine, the cylinder block comprises six cylinder bores.

[0018] In a further aspect of the monoblock engine, each cylinder bore comprises a cylinder liner, the cylinder liner covering the at least two indentations.

[0019] In a further embodiment of the present disclosure, a monoblock engine comprises a cylinder head, a cylinder block positioned adjacent the cylinder head, the cylinder block comprising at least one cylinder bore having a first end and a second end, and an upper crank case positioned adjacent the cylinder head, the upper crank case comprising at least a portion of at least one main bearing having a first side and a second side, wherein the second end of the at least one cylinder bore and the first side and the second side of the portion of the at least one main bearing comprise at least one indentation.

[0020] In one aspect of the monoblock engine, the upper crank case further comprises at least one bearing insert, the bearing insert covering the at least one indentation.

[0021] In another aspect of the monoblock engine, the at least one cylinder bore further comprises a cylinder liner, the cylinder liner covering the at least one indentation.

[0022] In a further aspect of the monoblock, the at least one cylinder bore comprises at least two indentations, the at least two indentations being rounded.

BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Advantages and features of the embodiments of this disclosure will become more apparent from the following detailed description of exemplary embodiments when viewed in conjunction with the accompanying drawings, wherein: [0024] FIG. 1 is a perspective view of an inverted configuration of an embodiment of a monoblock engine of the present disclosure including a portion of a plurality of crankshaft bearings;

[0025] FIG. 2 is an exploded view of the monoblock engine of FIG. 1;

[0026] FIG. 3 is a bottom plan view of the monoblock engine of FIG. 1 without the crankshaft bearings;

[0027] FIG. 4 is a cross-sectional view of the monoblock engine of FIG. 1 taken along line 4-4 of FIG. 1 including a plurality of cylinder bores having cylinder liners with one cylinder bore being shown without a cylinder liner;

[0028] FIG. 5 is a detailed view of the monoblock engine of FIG. 4 without the crankshaft bearings and the cylinder liners; and

[0029] FIG. 6 is a cross-sectional view of the monoblock engine of FIG. 1 taken along line 6-6 of FIG. 1 including an outline of a valve seat tool.

[0030] Corresponding reference characters indicate corresponding parts throughout the several views. Although the drawings represent embodiments of the present disclosure, the drawings are not necessarily to scale and certain features may be exaggerated in order to better illustrate and explain the present disclosure. The exemplifications set out herein illustrate embodiments of the disclosure, in one form, and such exemplifications are not to be construed as limiting the scope of the disclosure in any manner.

DETAILED DESCRIPTION OF THE DRAWINGS

[0031] Referring to FIGS. 1 and 2, a monoblock engine 10 generally includes a cylinder head 12, a cylinder block 14 positioned adjacent cylinder head 12, and an upper crank case 16 positioned adjacent cylinder block 14. In one embodiment, cylinder block 14 is positioned below cylinder head 12, and upper crank case 16 is position below cylinder block 14 when engine 10 is positioned within a vehicle (not shown). In the illustrative embodiments, monoblock engine 10 is shown in an inverted configuration in order to show an interior portion 15 of upper crank case 16.

[0032] With reference to FIGS. 2 and 3, upper crank case 16 generally includes an outer wall 19 which defines interior portion 15 and at least one main bearing 18. Outer wall 19 includes side walls 17 and outer main bearings 18b. Inner main bearings 18a extend between side walls 17. While upper crank case 16 is depicted as including three inner main bearings 18a, it should be understood that more or fewer than three inner main bearings 18a may be used depending upon the number of engine cylinders.

[0033] Each of outer main bearings 18b and inner main bearings 18a include at least one indentation 22 formed into at least one side surface of the bearing. In the illustrative

embodiment of FIG. 3, each of inner main bearings 18a includes two indentations 22, one formed into side surface 24 and another formed into side surface 26. Each of outer main bearings 18b includes one indentation 22 formed into side surface 28 facing inward towards interior portion 15 of crank case 16. In various embodiments, outer main bearings 18b may include indentations 22 on both side surface 28 and side surface 29 (shown as substantially straight in Figure 3). As shown in the illustrative embodiment of FIG. 3, indentations 22 may be rounded and substantially conform to the outer circumference of the pistons (not shown) of the engine.

[0034] Indentations 22 of main bearings 18a, 18b allow cylinder bores 30 (FIGS. 3 and

5) to be machined and pistons (not shown) for each cylinder bore 30 to be assembled while permitting upper crank case 16, cylinder body 14, and cylinder head 12 to remain a single integral component. More specifically, indentations 22 provide a clearance larger than cylinder bores 30 which allows piston rings of the pistons to pass through and/or into cylinder bores 30.

[0035] Main bearings 18a, 18b form the upper portions of the main crankshaft bearing.

After the crankshaft is in place, lower crank case (not shown) is attached to upper crank case 16 to capture the crankshaft. The lower crank case includes corresponding lower portions of the main crankshaft bearing. The upper portions (i.e., main bearings 18a, 18b) may survive with less surface area (i.e., as a result of indentations 22) than the lower portions of the crankshaft bearing (not shown) because upper portions (i.e., main bearings 18a, 18b) only receive inertial forces of the reciprocating components of engine 10. The lower portions must withstand the downward forces applied by the connecting rods as a result of the combustion events in the cylinders. The lower portions may be individual bearing caps or integrated into a bed plate that houses all lower portions of engine 10 in a single piece (not shown). During assembly and use, crankshaft bearing inserts 20 are positioned within main bearings 18a, 18b for receiving the crankshaft (not shown) of engine 10. With inserts 20 in place, indentations 22 are covered and therefore unable to interfere with the performance of engine 10. [0036] Referring to FIGS. 4-6, cylinder block 14 generally includes at least one cylinder bore 30 having a first end 31 and a second end 33. First end 31 of cylinder bore 30 is proximate to cylinder head 12, while second end 33 is spaced apart from cylinder head 12 and proximate to upper crank case 16. In various embodiments, cylinder block 14 may generally include four or six cylinder bores 30, while in other embodiments cylinder block 14 may include any number of cylinder bores 30. In an illustrative embodiment, cylinder block 14 includes four cylinder bores 30.

[0037] Cylinder bore 30 generally includes at least two indentations 32 about second end

33. In general, cylinder bore 30 will include as many indentations 32 as there are valves 36 for each cylinder bore 30. As shown in the illustrative embodiment of FIGS. 4-6, indentations 32 may be generally rounded. Furthermore, as best shown in FIG. 6, each indentation 32 is generally positioned to be in line with the axis A of one of valves 36 such that a machining device or valve seat tool 40 may access and machine out pockets and/or valve seat bores 38 for each valve 36 while allowing cylinder head 12, cylinder block 14, and upper crank case 16 of engine 10 to remain an integral piece. In one embodiment, indentations 32 are of sufficient depth and/or length to allow valve seat tool 40 to have at least 2 millimeters of clearance when machining valve seat bores 38. During assembly and use, cylinder liners 35 may be used to cover indentations 32 of cylinder bore 30 so that indentations 32 do not interfere with the performance of engine 10. As shown in the illustrative embodiment of FIG. 4, cylinder liner 35 is positioned within cylinder bore 30 (left cylinder) such that indentation 32 of that particular cylinder bore 30 is covered. The cylinder bore 30 on the right side of FIG. 4 shows a cylinder bore without a cylinder liner 35, thereby leaving the indentation 32 exposed.

[0038] In various embodiments, engine 10 may include indentations 22 formed into main bearings 18a, 18b and indentations 32 formed into second end 33 of cylinder bores 30. As shown in the illustrative embodiment of FIG. 4, both indentations 22 and 32 may be rounded.

[0039] While various embodiments of the disclosure have been shown and described, it is understood that these embodiments are not limited thereto. The embodiments may be changed, modified and further applied by those skilled in the art. Therefore, these embodiments are not limited to the detail shown and described previously, but also include all such changes and modifications. [0040] Furthermore, the connecting lines shown in the various figures contained herein are intended to represent exemplary functional relationships and/or physical couplings between the various elements. It should be noted that many alternative or additional functional relationships or physical connections may be present in a practical system. However, the benefits, advantages, solutions to problems, and any elements that may cause any benefit, advantage, or solution to occur or become more pronounced are not to be construed as critical, required, or essential features or elements. The scope is accordingly to be limited by nothing other than the appended claims, in which reference to an element in the singular is not intended to mean "one and only one" unless explicitly so stated, but rather "one or more." Moreover, where a phrase similar to "at least one of A, B, or C" is used in the claims, it is intended that the phrase be interpreted to mean that A alone may be present in an embodiment, B alone may be present in an embodiment, C alone may be present in an embodiment, or that any combination of the elements A, B or C may be present in a single embodiment; for example, A and B, A and C, B and C, or A and B and C.

[0041] In the detailed description herein, references to "one embodiment," "an embodiment," "an example embodiment," etc., indicate that the embodiment described may include a particular feature, structure, or characteristic, but every embodiment may not necessarily include the particular feature, structure, or characteristic. Moreover, such phrases are not necessarily referring to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is submitted that it is within the knowledge of one skilled in the art with the benefit of the present disclosure to affect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described. After reading the description, it will be apparent to one skilled in the relevant art(s) how to implement the disclosure in alternative embodiments.

[0042] Furthermore, no element, component, or method step in the present disclosure is intended to be dedicated to the public regardless of whether the element, component, or method step is explicitly recited in the claims. No claim element herein is to be construed under the provisions of 35 U.S.C. § 112(f), unless the element is expressly recited using the phrase "means for." As used herein, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

Claims

WHAT IS CLAIMED IS:

1. A monoblock engine, comprising:

a cylinder head;

a cylinder block positioned adjacent the cylinder head and comprising at least one cylinder bore; and

an upper crank case positioned adjacent the cylinder block and comprising a portion of at least two main bearings, the portion having a first side and a second side, at least one of the first side and the second side having an indentation.

2. The monoblock engine of claim 1, wherein the upper crank case comprises a portion of at least three main bearings, the at least three main bearings comprising an inner main bearing extending across an interior of the upper crank case and outer main bearings, the inner main bearing having an indentation on both the first side and the second side and the outer main bearings each having an indentation on one of the first side and the second side.

3. The monoblock engine of claim 2, wherein the one of the first side or the second side of the outer main bearings comprising the indentation faces inward toward the interior of the upper crank case.

4. The monoblock engine of claim 2, wherein the cylinder block comprises four cylinder bores and the upper crank case comprises portions of at least five main bearings.

5. The monoblock engine of claim 1, wherein the at least one cylinder bore comprises a first end proximate the cylinder head, a second end spaced apart from the cylinder head and proximate the upper crank case, and at least two indentations disposed about the second end of the at least one cylinder bore.

6. The monoblock engine of claim 1, wherein the upper crank case further comprises a bearing insert positioned within each main bearing, the bearing insert covering the at least one indentation.

7. The monoblock engine of claim 1, wherein the at least one indentation permits machining of the at least one cylinder bore when the cylinder head, the cylinder block, and the upper crank case are a single component.

8. The monoblock engine of claim 1, wherein the at least one indentation permits a piston of the cylinder bore to be disposed within the cylinder bore when the cylinder head, the cylinder block, and the upper crank case are a single component.

9. The monoblock engine of claim 1, wherein the at least one indentation is rounded.

10. A monoblock engine comprising:

a cylinder head;

a cylinder block positioned adjacent the cylinder head, the cylinder block comprising at least one cylinder bore; and

an upper crank case positioned adjacent the cylinder head, wherein each cylinder bore comprises a first end proximate the cylinder head, a second end proximate the upper crank case, and at least two indentations disposed about the second end.

11. The monoblock engine of claim 10, wherein each cylinder bore comprises four indentations, the indentations being rounded.

12. The monoblock engine of claim 10, wherein the at least one cylinder bore comprises a first pass through clearance and the at least one indentation cooperates with the cylinder bore to provide a second pass through clearance that is larger than the first pass through clearance.

13. The monoblock engine of claim 10, wherein the at least two indentations permit a machining device to access and machine out valve seat bores of at least two valves within the cylinder head when the cylinder head, the cylinder block, and the upper crank case are a single component.

14. The monoblock engine of claim 10, wherein the cylinder block comprises four cylinder bores.

15. The monoblock engine of claim 10, wherein the cylinder block comprises six cylinder bores.

16. The monoblock engine of claim 10, wherein each cylinder bore comprises a cylinder liner, the cylinder liner covering the at least two indentations.

17. A monoblock engine comprising:

a cylinder head;

a cylinder block positioned adjacent the cylinder head, the cylinder block comprising at least one cylinder bore having a first end and a second end; and

an upper crank case positioned adjacent the cylinder head, the upper crank case comprising at least a portion of at least one main bearing having a first side and a second side, wherein the second end of the at least one cylinder bore and the first side and the second side of the portion of the at least one main bearing comprise at least one indentation.

18. The monoblock engine of claim 17, wherein the upper crank case further comprises at least one bearing insert, the bearing insert covering the at least one indentation.

19. The monoblock engine of claim 17, wherein the at least one cylinder bore further comprises a cylinder liner, the cylinder liner covering the at least one indentation.

20. The monoblock engine of claim 17, wherein the at least one cylinder bore comprises at least two indentations, the at least two indentations being rounded.