JP2019105294A - gasket - Google Patents

Abstract

To provide a gasket which can equally seal a clearance between a cylinder head and a cylinder block.SOLUTION: A gasket 1 comprises: a lower-side baseboard 11 arranged at a cylinder block 3 side; an upper-side baseboard 12 arranged at a cylinder head 2 side; and a shim plate 13 arranged between the lower-side baseboard 11 and the upper-side baseboard 12. The shim plate 13 has annular wedge parts 13a which are arranged between a cylinder block side full-bead 11a arranged at the lower-side baseboard 11 and a cylinder head side full-bead part 12a arranged at the upper-side baseboard 12, and extend over a cylinder head face 21a. The shim plate 13 also has extension wedge parts 13b which are formed so as to extend from a part of the wedge parts 13a located at both sides in an alignment direction of the wedge parts 13a in a peripheral direction up to an outside upper face 32a of an outer wall 32 of the cylinder block 3 for defining a cooling water passage 60 together with a bore wall 31.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a gasket, and more particularly to a gasket used in an internal combustion engine such as a vehicle or a general purpose device.

  In vehicles and general-purpose machines such as automobiles, in internal combustion engines, gaskets are used to seal between a cylinder head and a cylinder block. The gasket is elastically deformed by being sandwiched between the cylinder head and the cylinder block, thereby sealing the cylinder head and the cylinder block and sealing the internal combustion engine (for example, Patent Document 1).

  FIG. 6 is a schematic perspective view showing a conventional four-cylinder internal combustion engine provided with a gasket, with the cylinder head removed. FIG. 7 is a cross-sectional view showing a cross section taken along line C-C in FIG. 6 including the cylinder head and the cylinder block. As shown in FIGS. 6 and 7, the internal combustion engine 100 includes a cylinder head 200, a cylinder block 300, and a gasket 400.

  The cylinder block 300 has a plurality of bore walls 310 including an annular deck surface 311 which is a surface facing the cylinder head 200. As shown in FIG. 6, the bore walls 310 of the cylinder block 300 annularly surround the bore holes 320 respectively arranged in series. The cylinder head 200 has a base 210 including a cylinder head surface 211 which is a surface facing the deck surface 311 of the cylinder block 300.

  The gasket 400 is disposed on the side of the cylinder head 200, and includes an upper base 410 having an annular cylinder head side full bead 411 and a lower side having an annular cylinder block side full bead 421 on the side of the cylinder block 300. A side substrate 420 and a shim plate 430 having an annular ridge 431 disposed between the upper substrate 410 and the lower substrate 420 are included.

  In the conventional internal combustion engine 100, the cylinder head 200 and the cylinder block 300 are fastened using a plurality of bolts 500 and 501. As shown in FIG. 6, bolts 500 are four end bolts disposed at both ends in the row direction of bore holes 320, and bolts 501 are between the end bolts 500 in the row direction of bore holes 320. There are six inner bolts arranged.

  At the time of the above-mentioned fastening, the cylinder head side full bead portion 411, the cylinder block side full bead portion 421, and the collar portion 431 are overlapped and held between the cylinder head surface 211 and the deck surface 311. Thus, the flange 431 is sandwiched between the cylinder head surface 211 and the deck surface 311, and the cylinder head side full bead portion 411 and the cylinder block side full bead portion 421 are elastically deformed, whereby the end bolt 500 and the inner side bolt When strongly pressed by 501, the gap between the cylinder head 200 and the cylinder block 300 generated between each of the bolts 500, 501 is filled to secure sealing performance.

JP 2001-227410 A

  However, in the conventional gasket 400, even if the end bolt 500 and the inner bolt 501 are tightened with the same torque, the pressing deformation force applied by the end bolt 500 (the cylinder head surface 211 and the deck surface 311) The surface pressure) is larger than the pressing deformation force (surface pressure) applied by the inner bolt 501.

  Therefore, when the cylinder head 200 and the cylinder block 300 are fastened, the clearance between the portion of the cylinder head surface 211 which receives the pressing deformation force by the inner bolt 501 and the portion of the deck surface 311 is an end portion. It deforms so as to be larger than the gap between the portion of the cylinder head surface 211 which receives the pressing deformation force by the bolt 500 and the portion of the deck surface 311. Thus, when the cylinder head 200 and the cylinder block 300 are fastened using the conventional gasket 400, the gap between the cylinder head surface 211 and the deck surface 311 becomes uneven in the direction in which the bore holes 320 are arranged. The conventional gasket 400 has not been sufficiently configured to achieve even sealing between the cylinder head 200 and the cylinder block 300.

  The present invention has been made in view of the above-described problems, and an object thereof is to provide a cylinder head in the direction in which the bores are arranged such that the gap between the cylinder head surface and the deck surface of the cylinder block becomes uneven. It is an object of the present invention to provide a gasket capable of preventing deformation of the cylinder head and achieving uniform sealing between the cylinder head and the cylinder block.

  In order to achieve the above object, a gasket according to the present invention is a gasket mounted between a cylinder head and a cylinder block of an internal combustion engine, and a flat lower substrate disposed on the side of the cylinder block And a flat plate-like upper substrate disposed on the side of the cylinder head, and a flat plate-like shim plate disposed between the lower substrate and the upper substrate, the lower substrate comprising An annular cylinder block side full bead portion corresponding to each of the annular deck surfaces of the bore walls of the cylinder block, the upper substrate being a surface facing each of the deck surfaces; An annular cylinder head full bead portion facing the cylinder block side full bead portion corresponding to each of the cylinder head surfaces, the shim plate being the cylinder block An annular collar portion is disposed between the full bead portion and the cylinder head side full bead portion and extends over the cylinder head surface, and the shim plates are positioned at both ends in the row direction of the collar portions. It is characterized by having an extended ridge part formed so that it might extend from a part in the peripheral direction of the ridge part to the outside upper surface of the outer wall of the cylinder block which defines a cooling water passage with the bore wall.

  In the gasket according to one aspect of the present invention, each of the extension collars extends in opposite directions in a row direction of the collars.

  In the gasket according to one aspect of the present invention, the lower substrate has a cylinder block side cooling water half bead portion corresponding to the outer upper surface of the cylinder block, and the upper substrate faces the outer upper surface. A cylinder head side cooling water half bead portion corresponding to the cylinder block side cooling water half bead portion corresponding to the outer lower surface of the cylinder head, and the extension collar portion is the cylinder block side cooling water half bead portion and the cylinder bead side cooling water half bead portion It is formed so as not to reach the cylinder head side cooling water half bead portion.

  In the gasket according to one aspect of the present invention, a bead height in a vertical direction of a portion of the cylinder block side cooling water half bead portion and the cylinder head side cooling water half bead portion where the extension collar portion is disposed is It is higher than the bead height of the part where the extension collar part is not disposed.

  In the gasket according to one aspect of the present invention, the extension collar is integrally formed with the collar.

  The gasket according to an aspect of the present invention further includes a flat plate-like middle plate disposed between the lower substrate and the shim plate.

  In the gasket according to one aspect of the present invention, the extension collar is separate from the collar, and the extension collar has a thickness different from the thickness of the collar.

  According to the gasket of the present invention, it is possible to suppress the deformation of the cylinder head in the direction in which the bores are arranged so that the gap between the cylinder head surface and the deck surface of the cylinder block becomes nonuniform. Even sealing between the blocks can be achieved.

1 is a schematic perspective view showing a four-cylinder internal combustion engine provided with a gasket according to an embodiment of the present invention in a state in which a cylinder head is removed. It is sectional drawing which shows the cross section along the AA in FIG. 1 including a cylinder head and a cylinder block. It is sectional drawing which shows the cross section along the BB line in FIG. 1 including a cylinder head and a cylinder block. It is a sectional view showing a section of an internal-combustion engine provided with a gasket concerning another embodiment of the present invention including a cylinder head and a cylinder block. FIG. 6 is a cross-sectional view showing a cross section of an internal combustion engine provided with a gasket according to still another embodiment of the present invention, including a cylinder head and a cylinder block. FIG. 8 is a schematic perspective view showing a conventional four-cylinder internal combustion engine provided with a gasket, with the cylinder head removed. FIG. 7 is a cross-sectional view showing a cross section taken along the line C-C in FIG. 6 including a cylinder head and a cylinder block.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic perspective view showing a four-cylinder internal combustion engine 70 provided with a gasket 1 according to an embodiment of the present invention, with the cylinder head 2 removed, and FIG. FIG. 2 is a cross-sectional view showing a cross section taken along the line A, including the cylinder head 2 and the cylinder block 3;

  Here, in the following description, the upper side or the upper side (the direction of the arrow a in FIGS. 1 and 2) is the side or the direction in which the cylinder head 2 is provided in the internal combustion engine 70, and the lower side or the lower side The arrows 1 and 2 in the directions 1 and 2 are the side or the direction in which the cylinder block 3 is provided in the internal combustion engine 70. The outer or outer direction (the direction of the arrow c in FIGS. 1 and 2) is the side or direction outside the cylinder block 3 in the alignment direction of the bore holes 31b of the cylinder block 3 described later. The direction of the arrow d in FIGS. 1 and 2 is the side or direction inside the cylinder block 3 in the direction in which the bore holes 31 b are arranged.

  As shown in FIGS. 1 and 2, the gasket 1 according to the present embodiment is attached between the cylinder head 2 and the cylinder block 3 of the internal combustion engine 70. The gasket 1 has a flat lower substrate 11 disposed on the side of the cylinder block 3, a flat upper substrate 12 disposed on the side of the cylinder head 2, a lower substrate 11, and an upper substrate 12. And a flat shim plate 13 disposed between the two.

  The lower substrate 11 has an annular cylinder block side full bead portion 11 a corresponding to each of the annular deck surfaces 31 a of the bore walls 31 of the cylinder block 3. Further, as shown in FIG. 2, the lower substrate 11 has a cylinder block side cooling water half bead portion 11 b corresponding to the outer upper surface 32 a of the cylinder block 3. Specifically, the cylinder block side full bead portion 11a is formed in a direction (downward direction) to project from the shim plate 13 so as to apply a predetermined surface pressure to the deck surface 31a of the cylinder block 3 in a use state described later It is done. The cylinder block side full bead portion 11a may be formed in a direction (upward direction) approaching the shim plate 13 so as to apply a predetermined surface pressure to the deck surface 31a in the use state. Further, the cylinder block side cooling water half bead portion 11b is formed in a direction (downward direction) protruding from the shim plate 13 so as to apply a predetermined surface pressure to the outer upper surface 32a of the cylinder block 3 in a use state described later. ing.

  The upper substrate 12 has an annular cylinder head full bead portion 12 a facing the cylinder block side full bead portion 11 a corresponding to each of the cylinder head surfaces 21 a of the cylinder head 2 which is a surface facing each of the deck surfaces 31 a. Further, the upper substrate 12 has a cylinder head side cooling water half bead portion 12 b corresponding to the cylinder block side cooling water half bead portion 11 b corresponding to the outer lower surface 21 b of the cylinder head 2 which is a surface opposite to the outer upper surface 32 a. Specifically, the cylinder head side full bead portion 12a is formed in a direction (upward direction) protruding from the shim plate 13 so as to apply a predetermined surface pressure to the cylinder head surface 21a in a use state described later . The cylinder head side full bead portion 12a may be formed in a direction (downward direction) approaching the shim plate 13 so as to apply a predetermined surface pressure to the cylinder head surface 21a in the use state. Further, the cylinder head side cooling water half bead portion 12b is formed in a direction (upward direction) protruding from the shim plate 13 so as to apply a predetermined surface pressure to the outer lower surface 21b of the cylinder head 2 in a use state described later. ing.

  The shim plate 13 is disposed between the cylinder block side full bead portion 11a and the cylinder head side full bead portion 12a, and has an annular collar portion 13a extending over the cylinder head surface 21a. The shim plate 13 has an outer wall 32 of the cylinder block 3 that defines the cooling water passage 60 together with the bore wall 31 from a part in the circumferential direction of the ridge portion 13a located at both ends (outside in FIG. 1) in the row direction And an extended collar portion 13b formed to extend to the outer upper surface 32a.

  The extension collar portion 13b extends outward from a part of the collar portion 13a in the circumferential direction. For example, each of the extension collar portions 13b preferably extends in mutually opposite directions in the row direction of the collar portions 13a. . Further, it is preferable that the extension collar 13 b is formed so as not to reach the cylinder block side cooling water half bead portion 11 b and the cylinder head side cooling water half bead portion 12 b. The extension collar 13b may be integrally formed with the collar 13a.

  As shown in FIG. 2, the bead height H in the vertical direction of the portion of the cylinder block side cooling water half bead portion 11b and the cylinder head side cooling water half bead portion 12b where the extension collar portion 13b is disposed is the extension collar portion Preferably, it is higher than the bead height of the portion where 13b is not disposed. The cylinder block side cooling water half bead portion 11b and the cylinder head side cooling water half bead portion 12b are formed narrower than the bead width W of the portion where the extension collar portion 13b is not disposed in the portion where the extension collar portion 13b is disposed. It may be done.

  Specifically, as shown in FIG. 2, in the use state described later, the gasket 1 covers the entire circumference of the cylinder block side full bead portion 11a and the cylinder head side full bead portion 12a by the cylinder head surface 21a and the deck surface 31a. The cylinder block side cooling water half bead portion 11b and the cylinder head side cooling water half bead portion 12b, which will be described later, are formed so as to be held along the entire circumference by the outer lower surface 21b and the outer upper surface 32a.

  Specifically, as shown in FIG. 2, the lower substrate 11 extends from the outer end portion of the cylinder block side full bead portion 11a toward the outer wall 32 of the cylinder block 3 in the natural state where no load is applied, It is a plate-like member having a constant or substantially constant thickness and extending in a bent and inclined manner at a position corresponding to the outer upper surface 32 a of the outer wall 32. The lower substrate 11 forms a cylinder block side cooling water half bead portion 11 b at a position corresponding to the outer upper surface 32 a. Further, as shown in FIG. 1, the lower substrate 11 is formed with a plurality of lower insertion holes 11c through which bolts 40 and 41 described later are respectively inserted. As shown in FIG. 1, the bolts 40 are four end bolts arranged at both ends (outside) in the direction in which the bore holes 31b are arranged, and the bolts 41 are ends in the direction in which the bore holes 31b are arranged. There are six inner bolts located between the bolts 40.

  Specifically, as shown in FIG. 2, in the natural state where no load is applied, the upper substrate 12 is directed from the outer end portion of the cylinder head full bead 12 a toward the outer lower surface 21 b of the cylinder head 2. It is a plate-like member having a constant or substantially constant thickness and extending in a bent and inclined manner at a position corresponding to the outer lower surface 21 b of the cylinder head 2. The upper substrate 12 forms a cylinder head side cooling water half bead portion 12 b at a position corresponding to the outer lower surface 21 b. Further, as shown in FIG. 1, the upper substrate 12 is formed with a plurality of upper insertion holes 12c through which end bolts 40 and inner bolts 41 described later are respectively inserted.

  Specifically, as shown in FIG. 2, the extension collar portion 13 b terminates in front of the cylinder block side cooling water half bead portion 11 b and the cylinder head side cooling water half bead portion 12 b on the outer upper surface 32 a of the cylinder block 3. It is preferable that the That is, the extension collar portion 13b is formed so as not to be held by the cylinder block side cooling water half bead portion 11b and the cylinder head side cooling water half bead portion 12b when the gasket 1 described later is in use. For example, as shown in FIG. 1, the extension collar 13 b may be a substantially rectangular member extending outward so as to have a constant or substantially constant circumferential length along the circumferential direction of the collar 13 a ( See the upper extension collar 13 b in FIG. Further, the extension collar portion 13b may be a member having a shape in which the circumferential length along the circumferential direction of the collar portion 13a changes outward (see the lower extension collar portion 13b in FIG. 1). In addition, the shape of the extension collar part 13b is not limited to this, For example, the shape corresponding to the shape of the cooling water channel 60 may be sufficient.

  Next, the operation of the gasket 1 according to the present embodiment will be described. As shown in FIG. 2, the gasket 1 is engaged by a predetermined method (for example, caulking etc.) so that the shim plate 13 is sandwiched between the lower side substrate 11 and the upper side substrate 12 and integrally integrated in a mutually overlapped state. It is stopped. At this time, in the shim plate 13, each of the ridge portions 13 a of the shim plate 13 is disposed between the cylinder block side full bead portion 11 a and the cylinder head side full bead portion 12 a, and each of the extension ridge portions 13 b of the shim plate 13. Is disposed between the lower substrate 11 and the upper substrate 12 so as not to reach the cylinder block side cooling water half bead portion 11 b and the cylinder head side cooling water half bead portion 12 b.

  The gasket 1 thus integrated is placed at a predetermined position of the cylinder block 3. Specifically, as shown in FIGS. 1 and 2, in the gasket 1, the cylinder block side cooling water half bead portion 11b is disposed on the outer upper surface 32a of the cylinder block 3, and each of the cylinder block side full bead portions 11a has a bore wall. The cylinder is disposed on each of the deck surfaces 31a of the cylinder 31, and the lower insertion hole 11c and the upper insertion hole 12c communicate with the bolt holes 33 formed in the outer upper surface 32a of the cylinder block 3, respectively. Placed on block 3 At this time, dowel pins (not shown) are inserted in advance into two bolt holes 33 d (see FIG. 1) of the bolt holes 33 of the cylinder block 3, and the dowel pins correspond to the respective bolt holes 33 d. The gasket 1 is positioned with respect to the cylinder block 3 by penetrating each of the insertion holes 11 cd and the upper insertion holes 12 cd.

  Here, FIG. 3 is a cross-sectional view showing a cross section taken along the line B-B in FIG. 1 including the cylinder head 2 and the cylinder block 3. As described above, with the gasket 1 mounted on the cylinder block 3, each of the end bolt 40 and the inner bolt 41 is provided on a predetermined bolt hole provided on the cylinder head 2 not shown in FIG. The upper insertion hole 12 c of the base plate 12 and the lower insertion hole 11 c of the lower base plate 11 are screwed with the female screw thread formed in the bolt hole 33 of the cylinder block 3 while penetrating through the lower insertion hole 11 c. Thus, the cylinder head 2 and the cylinder block 3 are fastened, and the cylinder head side full bead portion 12a, the cylinder block side full bead portion 11a, and the collar portion 13a are elastic between the cylinder head surface 21a and the deck surface 31a. While being deformed, the cylinder head side cooling water half bead portion 12b, the cylinder block side cooling water half bead portion 11b, and the extension collar portion 13b are elastically deformed between the outer upper surface 32a and the outer lower surface 21b, and the cylinder head 2 and cylinder The gaps between the blocks 3 are filled to ensure sealing.

  As described above, when the end bolt 40 and the inner bolt 41 are tightened with the same torque, most of the pressing deformation force (surface pressure) applied to the cylinder block 3 by the inner bolt 41 is the alignment of the bore holes 31b. It is added to the part of the deck surface 31a located inward in the direction (see P3 in FIG. 3). On the other hand, since the extension flange 13b of the shim plate 13 extends to the outer upper surface 32a of the cylinder block 3, most of the pressing deformation force (surface pressure) applied to the cylinder block 3 by the end bolt 40 is a bore. It is added to the deck surface 31a (see P2 in FIG. 3) and the outer top surface 32a of the cylinder block 3 (see P1 in FIG. 3) located at both ends (outside) in the arranging direction of the holes 31b.

  Thus, by using the gasket 1, the pressing deformation forces P1 to P3 applied by the end bolt 40 and the inner bolt 41 are each of the deck surface 31a, the cylinder head surface 21a, the outer upper surface 32a, and the outer lower surface 21b. It is intended to be paid by the Therefore, when the cylinder head 2 and the cylinder block 3 are fastened, the clearance between the deck surface 31a receiving the pressing deformation force P3 by the inner bolt 41 and the cylinder head surface 21a is the pressing deformation force P2 by the end bolt 40. The clearance between the receiving deck surface 31a and the cylinder head surface 21a, and the clearance between the outer upper surface 32a and the outer lower surface 21b receiving the pressing deformation force P1 by the end bolt 40, in the bore hole 31b Uneven deformation of the cylinder heads 2 in the alignment direction is suppressed, and uniform sealing between the cylinder heads 2 and the cylinder block 3 is achieved.

  Further, in the use state of the gasket 1, the extension collars 13b extend in opposite directions to each other in the row direction of the collars 13a, and therefore, the pressing deformation forces P1 to P3 applied by the end bolts 40 and the inner bolts 41. In each of the deck surface 31a, the cylinder head surface 21a, the outer upper surface 32a, and the outer lower surface 21b, the load is equally applied in the row direction of the collars 13a. Therefore, non-uniform deformation of the cylinder head 2 in the direction in which the bore holes 31 b are arranged is further suppressed, and uniform sealing between the cylinder head 2 and the cylinder block 3 is further achieved.

  Further, since the extension ridge 13b of the shim plate 13 is formed so as not to reach the cylinder block side cooling water half bead portion 11b and the cylinder head side cooling water half bead portion 12b, the cylinder block side cooling water half bead portion 11b and the cylinder A constant elastic deformation over the entire head side cooling water half bead portion 12 b can be secured, and appropriate sealing between the outer upper surface 32 a of the cylinder block 3 and the outer lower surface 21 b of the cylinder head 2 can be achieved.

  Further, in the natural state where no load is applied, the gasket 1 is a bead in the vertical direction of the portion of the cylinder block side cooling water half bead portion 11 b and the cylinder head side cooling water half bead portion 12 b where the extension collar portion 13 b is disposed. The height H (see FIG. 2) is formed to be higher than the bead height of the portion where the extension collar 13b is not disposed. As described above, the cylinder block side cooling water half bead portion 11b and the cylinder head side cooling water half bead portion 12b are formed such that the bead height H is increased according to the extension collar portion 13b, so the use state of the gasket 1 In the above, the desired elastic deformation over the entire cylinder block side cooling water half bead portion 11b and the cylinder head side cooling water half bead portion 12b can be secured, and the outer upper surface 32a of the cylinder block 3 and the outer lower surface 21b of the cylinder head 2 It is possible to achieve a more appropriate sealing between

  Further, since the cylinder block side cooling water half bead portion 11 b and the cylinder head side cooling water half bead portion 12 b are formed such that the bead width W (see FIG. 2) becomes narrow according to the extension collar portion 13 b Desired elastic deformation over the whole of the cylinder block side cooling water half bead portion 11 b and the cylinder head side cooling water half bead portion 12 b can be secured in the use state, and the outer upper surface 32 a of the cylinder block 3 and the outer lower surface of the cylinder head 2 A more appropriate seal with 21b can be achieved.

  As described above, according to the gasket 1 according to the embodiment of the present invention, the cylinder head 2 in the arrangement direction of the bore holes 31 b is configured such that the gap between the deck surface 31 a and the cylinder head surface 21 a is uneven. Deformation can be suppressed, and uniform sealing between the cylinder head 2 and the cylinder block 3 can be achieved.

  Next, a gasket 1a according to another embodiment of the present invention will be described with reference to FIG. FIG. 4 is a cross-sectional view showing a cross section of an internal combustion engine 70a provided with a gasket 1a according to another embodiment of the present invention, including the cylinder head 2 and the cylinder block 3.

  The gasket 1 a includes a flat plate-like middle plate 14 disposed between the lower substrate 11 and the shim plate 13. The middle plate 14 may be disposed between the upper substrate 12 and the shim plate 13. The middle plate 14 is a member formed in substantially the same shape as the lower side substrate 11 and the upper side substrate 12, and depending on the configuration of the lower side substrate 11 and the upper side substrate 12, the lower side insertion hole 11 c and the upper side insertion hole 12 c Corresponding holes for bolts, not shown, holes for oil, holes for cooling water, etc. are appropriately provided. Since the configuration of the middle plate 14 itself is known, the detailed description thereof is omitted.

  The middle plate 14 has an edge portion 14 a formed so as to be held by the lower substrate 11 and the upper substrate 12 in the assembled state of the gasket 1 a. The thickness of the middle plate 14 may be thicker, thinner, or the same or substantially the same as the thickness of the lower substrate 11 and the upper substrate 12.

  As described above, according to the gasket 1a according to another embodiment of the present invention, since the middle plate 14 having a predetermined thickness is further provided in addition to the extension collar portion 13b of the shim plate 13, the cylinder In accordance with the gap between the head 2 and the cylinder block 3, an appropriate thickness of the gasket 1a is secured. Therefore, even if the gap between the cylinder head 2 and the cylinder block 3 is changed due to the change of the shapes of the cylinder head 2 and the cylinder block 3, etc., between the deck surface 31a and the cylinder head surface 21a. The deformation of the cylinder head 2 in the direction in which the bore holes 31b are arranged can be suppressed so that the gap between the cylinder head 2 and the cylinder block 3 becomes uneven.

  Next, a gasket 1b according to still another embodiment of the present invention will be described with reference to FIG. FIG. 5 is a cross-sectional view showing a cross section of an internal combustion engine 70b provided with a gasket 1b according to still another embodiment of the present invention, including the cylinder head 2 and the cylinder block 3.

  The gasket 1b has an extension collar 13c separate from the collar 13a, and the extension collar 13c has a thickness different from the thickness of the collar 13a. The thickness of the extension collar 13c is preferably greater than the thickness of the collar 13a.

  The extension collar 13c has a flat plate-like inner flat plate 13ca fixed by spot welding 15 or the like to an end edge 13ae which is an outer end portion of the collar 13a, and a flat plate on the upper side and outside of the inner flat plate 13ca. And a step 13cc connecting the inner flat plate 13ca and the outer flat plate 13cb. The shape of the extension collar 13c is not limited to this. For example, the extension collar 13c does not have the step 13cc, and the inner flat portion 13ca and the outer flat portion 13cb are flush or substantially flush. It may be formed to be

  As described above, according to the gasket 1b according to still another embodiment of the present invention, since the extension collar 13c is provided separately from the collar 13a of the shim plate 13, the extension collar 13c can be , And a thickness different from the thickness of the ridge portion 13a. In particular, it is preferable to make the thickness of the extension collar 13c thicker than the thickness of the collar 13a, whereby the amount of elastic deformation of the extension collar 13c can be changed according to the thickness of the extension collar 13c, It is possible to reduce the pressing deformation force (P1 in FIG. 3) applied to the outer upper surface 32a of the cylinder block 3 by the end bolt 40. Therefore, it is possible to suppress excessive application of the pressing deformation force P1 by the end bolt 40 to the outer upper surface 32a of the cylinder block 3, and the gap between the deck surface 31a and the cylinder head surface 21a is uneven. Thus, the deformation of the cylinder head 2 in the direction in which the bore holes 31b are arranged can be suppressed, and an even sealing between the cylinder head 2 and the cylinder block 3 can be achieved.

  Next, other effects that can be exhibited by the gaskets 1, 1a and 1b according to the embodiment of the present invention will be described.

  According to the gaskets 1, 1a, 1b according to the embodiment of the present invention, as shown in FIG. 3, the pressing deformation forces P1, P2 applied by the end bolts 40 are the deck surface 31a, the cylinder head surface 21a, the outside Each of the upper surface 32a and the outer lower surface 21b is intended to be equally loaded, so that the pressing deformation forces P1 and P2 by the end bolt 40 are located at both ends in the alignment direction of the bore holes 31b. The concentrated application to the deck surface 31 a of the wall 31 can be avoided. Therefore, it is possible to suppress inward (in the direction of the arrow d) the deck surfaces 31a of the bore walls 31 located at both ends in the direction in which the bore holes 31b are lined by the pressing deformation forces P1 and P2 of the end bolts 40. . Thus, the inner diameter of the bore 31b can be maintained uniformly in the vertical direction, and the increase in friction between the piston sliding on the bore 31b and the bore wall 31 can be suppressed.

  Further, according to the gaskets 1, 1a and 1b according to the embodiment of the present invention, the cylinder head in the direction in which the bore holes 31b are arranged such that the gap between the deck surface 31a and the cylinder head surface 21a becomes uneven. Since the deformation of 2 can be suppressed, the coaxiality of a plurality of insertion holes for the camshaft (not shown) formed in the cylinder head 2 can be secured. For this reason, it is possible to suppress an increase in sliding resistance in driving the camshaft.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to the gasket 1 which concerns on the said embodiment of this invention, All the aspects contained in the concept of this invention, and a claim Including. In addition, the respective configurations may be selectively combined as appropriate so as to achieve at least a part of the problems and the effects described above. The shape, material, arrangement, size, and the like of each component in the above embodiment can be appropriately changed according to the specific use mode of the present invention.

  1, 1a, 1b, 400: Gasket, 11, 420: Lower substrate, 11a, 421: Full block on cylinder block side, 11b: Cooling water half bead on cylinder block side, 11c, 11cd ... Lower insertion hole, 12, 410 ... Upper substrate, 12a, 411 ... Cylinder head side full bead portion, 12b ... Cylinder head side cooling water half bead portion, 12c, 12cd ... Upper insertion hole, 13, 430 ... Shim plate, 13a, 431 ... Ridge portion, 13ae, 14a ... End edge portion 13b, 13c: Extended ridge portion, 13ca: Inner flat portion, 13cb: Outer flat portion, 13cc: Step portion, 14: Middle plate, 15: Spot welding, 2, 200: Cylinder head, 21a, 211 Cylinder head surface, 21b: Outer lower surface, 3, 300: Cylinder block, 31, 310: Bore wall, 31a, 31 ... Deck surface, 31b, 320 ... Bore hole, 32 ... Outer wall, 32a ... Outer upper surface, 33, 33d ... Bolt hole, 40, 500 ... End bolt, 41, 501 ... Inner bolt, 60 ... Cooling water passage, 70, 70a, 70b, 100: internal combustion engine, 210: base body, a: upper side, upper direction, b: lower side, lower direction, c: outer side, outer direction, d: inner side, inner direction, H: bead height, P1 to P P3 ... pressing deformation force (surface pressure), W ... bead width

Claims (7)

A gasket mounted between a cylinder head and a cylinder block of an internal combustion engine, comprising:
A flat lower substrate disposed on the side of the cylinder block;
A flat upper substrate disposed on the side of the cylinder head;
A flat shim plate disposed between the lower substrate and the upper substrate;
The lower substrate has an annular cylinder block side full bead portion corresponding to each of the annular deck surfaces of the bore walls of the cylinder block,
The upper substrate has an annular cylinder head full bead portion facing the cylinder block side full bead portion corresponding to each of the cylinder head surfaces of the cylinder head which is a surface facing each of the deck surfaces,
The shim plate is disposed between the cylinder block side full bead portion and the cylinder head side full bead portion, and has an annular collar portion extending over the cylinder head surface,
The shim plate is formed to extend from a portion in a circumferential direction of the ridges located at both ends in the row direction of the ridges to an outer upper surface of an outer wall of the cylinder block that defines a cooling water passage with the bore wall. Gasket characterized by having an extended ridge part.   The gasket according to claim 1, wherein each of the extension collars extends in opposite directions in a row direction of the collars. The lower substrate has a cylinder block side cooling water half bead portion corresponding to the outer upper surface of the cylinder block,
The upper substrate has a cylinder head side cooling water half bead portion corresponding to the cylinder block side cooling water half bead portion corresponding to the outer side lower surface of the cylinder head which is a surface facing the outer side upper surface,
The gasket according to claim 1 or 2, wherein the extension collar portion is formed so as not to reach the cylinder block side cooling water half bead portion and the cylinder head side cooling water half bead portion.   The bead height in the vertical direction of the portion where the extension collar portion is arranged among the cylinder block side cooling water half bead portion and the cylinder head side cooling water half bead portion is the bead of the portion where the extension collar portion is not arranged The gasket according to claim 3, characterized in that it is higher than the height.   The gasket according to any one of claims 1 to 4, wherein the extension collar is integrally formed with the collar.   The gasket according to any one of claims 1 to 5, further comprising a flat plate-like middle plate disposed between the lower substrate and the shim plate. The extension collar is separate from the collar,
5. A gasket according to any one of the preceding claims, characterized in that the extension collar has a thickness different from that of the collar.

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