JP2005090311A - Cylinder head - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cylinder head capable of adjusting flow of engine cooling water flowing in a cooling water passage by a simple configuration. <P>SOLUTION: This cylinder head is constituted in such a way that a spacer 30 adjusting flow of engine cooling water is inserted into a spacer mounting hole 20 passing through a passage wall 18 of the cooling water passage 17 on an intake side among the cooling water passages 17 in which engine cooling water flows. The spacer 30 is provided with a spacer main body 38 having a characteristic that it swells by engine cooling water and inserted into the cooling water passage 17 through the spacer mounting hole 20 in the passage wall 18 and a support body 32 supporting the spacer main body 38 and mounted on the passage wall 18. The spacer mounting hole 20 in the passage wall 18 is sealed by swelling of the spacer main body 38. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a cylinder head in a water-cooled internal combustion engine, so-called engine.

2. Description of the Related Art Conventionally, in a water-cooled engine cylinder head, a rib that adjusts the flow of engine cooling water is formed on a passage wall of a cooling water passage (see, for example, Patent Documents 1 and 2).
JP 2002-339799 A JP 2003-120290 A

  The cylinder head is generally manufactured by casting using a sand mold. And the said rib is integrally formed in the casting process of the cylinder head. For this reason, the shape of the sand mold becomes complicated, and as a result, the manufacturing cost increases. In addition, every time the engine model is changed, the design of the rib corresponding to the engine is required, and the shape of the sand mold becomes complicated.

  The problem to be solved by the present invention is to provide a cylinder head capable of adjusting the flow of engine coolant flowing in the coolant passage with a simple configuration.

  The above-mentioned problem can be solved by a cylinder head having the gist of the configuration described in the appended claims. The “characteristic that expands due to engine cooling water” in this specification corresponds to a characteristic that expands due to absorption of engine cooling water, a characteristic that expands depending on the temperature of engine cooling water, and the like. In addition, “engine cooling water” in the present specification corresponds to water, LLC (long life coolant), antifreeze coolant, and the like.

  That is, according to the cylinder head described in claim 1, the flow of the engine coolant flowing in the coolant passage can be adjusted by a simple configuration in which the spacer is inserted into the hole of the passage wall of the coolant passage. .

  According to the cylinder head recited in claim 2 of the claims, since the spacer is inserted into the cooling water passage on the intake side of the cooling water passage, the overcooling on the intake side is prevented or reduced. By preferentially cooling the exhaust side, insufficient cooling can be prevented or reduced. For this reason, fuel efficiency can be expected to be improved by improving the heat balance of the cylinder head, the flow rate of engine cooling water can be reduced, fuel efficiency can be improved by reducing the size of the water pump and reducing the amount of work, etc. Can be expected.

Further, according to the cylinder head described in claim 3 of the claims, the spacer body of the spacer is inserted into the cooling water passage through the hole of the passage wall in a state before expansion, and supports the spacer body. Is mounted on the passage wall, whereby the spacer is provided on the cylinder head. And the spacer main body after mounting | wearing with a spacer expand | swells to a predetermined shape with the engine cooling water which flows through the inside of a cooling water channel | path.
by the way,
(1) Since the spacer main body is inserted into the cooling water passage through the hole in the passage wall in a state before expansion, the spacer main body can be easily inserted.
(2) Since the spacer main body expands to a predetermined shape by the engine cooling water, the spacer main body having a predetermined shape can be provided in the cooling water passage without requiring a special operation.
(3) By attaching the support to the passage wall, the spacer body can be easily positioned at a predetermined position in the cooling water passage.
Therefore, the assembling property of the spacer with respect to the cylinder head can be improved by the synergistic action of the above (1) to (3).

  In addition, according to the cylinder head described in claim 4 of the claims, since the hole of the passage wall is sealed by the expansion of the spacer body, a dedicated part for sealing the hole of the passage wall and the part Assembly man-hours can be omitted.

  Further, according to the cylinder head described in claim 5 of the claims, since the support body is attached to the passage wall by press-fitting into the hole of the passage wall, the support body is attached to the passage wall. It is possible to omit the dedicated parts and the assembly man-hours of the parts.

  Further, according to the cylinder head described in claim 6 of the claims, the spacer main body can be supported by a simple operation of sandwiching the support.

  According to the cylinder head of the present invention, the flow of engine coolant flowing through the coolant passage can be adjusted with a simple configuration in which a spacer is inserted into a hole in the passage wall of the coolant passage.

  Next, the best mode for carrying out the present invention will be described with reference to examples.

  A cylinder head according to an embodiment of the present invention will be described. The cylinder head in the present embodiment is manufactured by casting using a sand mold, for example, as an aluminum alloy casting. The cylinder head is used for a four-cylinder engine, for example.

  In FIG. 1, which shows a bottom view of the cylinder head, that is, a joint surface with respect to the cylinder block, the cylinder head 10 has combustion in each of the first cylinder # 1, the second cylinder # 2, the third cylinder # 3, and the fourth cylinder # 4. An intake port 12 and an exhaust port 14 that open to the chamber 11 are formed. Two intake ports 12 and two exhaust ports 14 are formed in parallel in one combustion chamber 11. The upstream side of both intake ports 12 of each combustion chamber 11 joins an intake passage 13 that opens to one side of the cylinder row (left side in FIG. 1). Further, the downstream side of both exhaust ports 14 of each combustion chamber 11 joins an exhaust passage 15 that opens to the other side of the cylinder row (the right side in FIG. 1). A plug mounting hole 16 for mounting a plug (not shown) is formed at the center of each combustion chamber 11.

  A cooling water passage 17 is formed in the cylinder head 10. The cooling water passage 17 extends in the combustion chamber 11 of each of the first cylinder # 1, the second cylinder # 2, the third cylinder # 3, and the fourth cylinder # 4 along the cylinder row direction (from bottom to top in FIG. 1). It is formed symmetrically so as to pass in order along the left and right sides. Although not shown, the cylinder head 10 is provided with a cooling water inlet communicating with the cooling water passage 17 on one side (lower part in FIG. 1) in the cylinder row direction and on the other side (upper part in FIG. 1). A cooling water outlet communicating with the cooling water passage 17 is provided. Therefore, the engine cooling water flows from the predetermined cooling water circuit into the cooling water passage 17 through the cooling water inlet, flows through the left and right cooling water passages 17, and then flows out to the cooling water circuit through the cooling water outlet. In the cylinder head 10, engine cooling water is passed between the cooling water passage 17 and the cooling water passage 17 of the cylinder block (not shown) on the passage wall (reference numeral 18) on the lower surface side of the cooling water passage 17. An appropriate number of water holes 19 that can be circulated are formed.

  In the present embodiment, in order to prevent or reduce overcooling on the intake side (left side in FIG. 1) and insufficient cooling on the exhaust side (right side in FIG. 1) in the cylinder head 10, in this embodiment, the engine in the cooling water passage 17 on the intake side. A spacer 30 for adjusting the flow of the cooling water is provided. When the spacer 30 is provided in the cylinder head 10, the passage wall 18 is formed with a substantially cylindrical spacer mounting hole 20 that penetrates the inside and outside of the cooling water passage 17 (see FIG. 3). The spacer mounting hole 20 can be easily formed in the same manner as the water hole 19 is formed by a sand mold at the time of casting. Further, the spacer mounting hole 20 is formed for each combustion chamber 11 at a side position on the intake side of the combustion chamber 11. Moreover, the attachment state of the spacer 30 is shown by FIG. 2, and the state before attachment of the spacer 30 is shown by FIG. The “spacer mounting hole 20” corresponds to a “hole penetrating the passage wall of the cooling water passage” in this specification.

As shown in FIG. 4, the spacer 30 includes a support body 32 and a spacer body 38.
The support 32 is formed in a substantially cup shape by press-molding a metal plate having a predetermined rigidity, for example, a stainless steel plate. The support 32 includes a disc-shaped bottom plate portion 33 (see FIG. 3), a cylindrical tubular portion 34 that rises on the outer peripheral edge of the bottom plate portion 33, and an inwardly folded upper end portion of the tubular portion 34. It has a tapered locking piece 35 that is bent and formed in an appropriate number at a predetermined interval in the circumferential direction.
The cylindrical portion 34 has an outer diameter 34d that can be press-fitted into the spacer mounting hole 20 of the cylinder head 10 and a height 34h that is smaller than the wall thickness 18t of the passage wall 18 (see FIG. 3).
The spacer main body 38 is substantially circular by an elastic material made of water-swelling foam rubber having a characteristic of swelling due to absorption of engine cooling water or heat-sensitive expansion foam rubber having a characteristic of expanding by the temperature of engine cooling water. It is formed in a column shape. The spacer main body 38 is formed with an outer diameter 38d that can be loosely fitted into the cylindrical portion 34 of the support body 32 before expansion, and that the leading end of the locking piece 35 can bite in. The spacer body 38 is formed with a height 38 h that is about 2.5 times the height 34 h of the cylindrical portion 34.
Then, the spacer main body 38 is inserted into the cylindrical portion 34 of the support body 32, and the distal end portion of the locking piece 35 bites into the spacer main body 38 using its elastic deformation, whereby the spacer main body 38 is inserted into the support body 32. It is supported by being sandwiched by the locking piece 35 (see FIGS. 2 and 3).

Next, the case where the above-described spacer 30 is attached to the cylinder head 10 will be described. In addition, all the four spacers 30 arranged in each spacer mounting hole 20 corresponding to each combustion chamber 11 of the cylinder head 10 are arranged in the same manner.
First, the spacer 30 is inserted into the spacer mounting hole 20 of the passage wall 18 of the cylinder head 10 (see the two-dot chain line 30 in FIG. 3). At this time, the spacer body 38 of the spacer 30 is inserted into the cooling water passage 17 through the spacer mounting hole 20 of the passage wall 18 in a state before expansion. Further, the support body 32 of the spacer 30 is attached to the passage wall 18 by being press-fitted into the spacer mounting hole 20 of the passage wall 18. Thereby, the spacer main body 38 can be easily positioned at a predetermined position in the cooling water passage 17. The degree of press-fit of the support 32 into the spacer mounting hole 20 is such that the bottom plate portion 33 is substantially flush with the lower surface of the cylinder head 10.

  As described above, the cylinder head 10 to which the spacer 30 is attached is coupled to a cylinder block (not shown) via a cylinder head gasket. Thereafter, for example, in a bench test when the engine is shipped at an engine assembly factory, or in a vehicle factory, the engine water jacket (including the cooling water passage 17) is filled with engine cooling water, and further the engine is tested. The

As described above, when the engine coolant is filled into the coolant passage 17 or when the engine coolant is heated by the test operation of the engine, as shown in FIG. Inflates into shape. As a result, at least a part of the passage area of the cooling water passage 17 is blocked. As a result, the flow of engine cooling water flowing through the cooling water passage 17 is adjusted, and the temperature distribution of the cylinder head 10 is improved. That is, since the spacer 30 is disposed in the cooling water passage 17 on the intake side, it is possible to prevent or reduce overcooling on the intake side of the cylinder head 10 and to preferentially cool the exhaust side of the cylinder head 10. can do.
In addition, the spacer body 38 can seal the spacer mounting hole 20 by expanding so that the spacer mounting hole 20 of the passage wall 18 is closed.

  According to the cylinder head 10 described above, the flow of the engine coolant flowing through the coolant passage 17 can be adjusted with a simple configuration in which the spacer 30 is inserted into the spacer mounting hole 20 of the passage wall 18 of the coolant passage 17. it can. That is, unlike the case of providing a conventional rib or the like, it is not necessary to cause problems such as a complicated shape of the sand mold or an increase in manufacturing cost. In addition, there is almost no need to change the design or complicate the design every time the engine model is changed. Furthermore, the size of the support body 32 of the spacer 30 corresponding to the characteristics of the engine, the increase / decrease of the volume of the spacer body 38, the selection of the arrangement position of the spacer 30, etc. are compared to the sand mold design change. It is possible to respond easily.

  In addition, since the spacer 30 is inserted in the cooling water passage 17 on the intake side of the cooling water passage 17, overcooling on the intake side is prevented or reduced, and cooling is prevented by preferentially cooling the exhaust side. Can be prevented or reduced. For this reason, fuel efficiency can be expected to be improved by improving the heat balance of the cylinder head 10, and it is possible to reduce the flow rate of engine cooling water, improving fuel efficiency by reducing the size of the water pump and reducing the amount of work. Etc. can be expected.

explain in detail. In the cylinder head 110 (see FIG. 5) without the spacer 30 (see FIG. 1), the flow rate of engine cooling water (see arrow Y1 in FIG. 5) flowing in the cooling water passage 17 on the intake side, and the exhaust side The flow rate of the engine coolant flowing through the coolant passage 17 (see arrow Y2 in FIG. 5) is substantially equal. The flow rate of the engine cooling water flowing through the intake side cooling water passage 17 is represented by the thickness of the arrow Y1 in FIG. 5, and the exhaust side cooling water passage 17 is represented by the thickness of the arrow Y2 in FIG. The flow rate of the engine coolant flowing through the inside is shown.
For this reason, it is predicted that overcooling occurs on the intake side and insufficient cooling occurs on the exhaust side. In the cylinder head 110 shown in FIG. 5, the configuration is the same as that of the cylinder head 10 except that the spacer 30 and the spacer mounting hole 20 in the cylinder head 10 of this embodiment are omitted. The description which attaches a code | symbol and overlaps is abbreviate | omitted.

By the way, with respect to the cylinder head 110 (see FIG. 5), the flow of engine cooling water by the cylinder head 10 of the present embodiment is as shown by arrows Y1 and Y2 in FIG. In addition, the thickness of the arrow Y1 and the arrow Y2 in FIG. 1 is represented according to the notation of the thickness of the arrows Y1 and Y2 in FIG.
That is, the flow rate of engine cooling water flowing in the cooling water passage 17 on the intake side (see arrow Y1) is reduced by the spacer 30, while the flow rate of engine cooling water flowing in the cooling water passage 17 on the exhaust side (arrow Y2). (Refer to “Reference.)” Is increased by adding a decrease in the cooling water passage 17 on the intake side. Therefore, overcooling on the intake side of the cylinder head 10 can be prevented or reduced, and insufficient cooling can be prevented or reduced by preferentially cooling the exhaust side. For this reason, generation | occurrence | production of the thermal distortion of the cylinder head 10 can be prevented or reduced.

Further, CAE analysis of the heat transfer coefficient (W / m ² · K) on the intake side and the exhaust side for each cylinder in the cylinder head of this embodiment and the cylinder head without the spacer is shown in FIG. Analysis results were obtained. In FIG. 6, “A” is data of the cylinder head (see FIG. 1) of this embodiment, and “B” is data of the cylinder head without the spacer (see FIG. 5).
As apparent from FIG. 6, in the data B of the cylinder head without the spacer (see FIG. 5), the heat transfer coefficient on the intake side and the heat transfer coefficient on the exhaust side are substantially equal. Compared to this, according to the data A of the cylinder head of this embodiment (see FIG. 1), the heat transfer coefficient on the intake side is small, and conversely, the heat transfer coefficient on the exhaust side (EX side) is a large value. .
Therefore, from the CAE analysis of the heat transfer coefficient, according to the cylinder head of this embodiment (see FIG. 1), the effect of preventing or reducing the overcooling on the intake side and preventing or reducing the insufficient cooling on the exhaust side. It can be seen that

Further, according to the cylinder head 10 (see FIG. 1) of the present embodiment, the spacer body 38 of the spacer 30 is inserted into the cooling water passage 17 through the spacer mounting hole 20 of the passage wall 18 in a state before expansion, and the spacer body. The spacer 32 is provided on the cylinder head 10 by mounting the support body 32 supporting the plate 38 on the passage wall 18 (see the two-dot chain line 30 in FIG. 3). Then, the spacer main body 38 after the spacer 30 is mounted expands into a predetermined shape by the engine coolant flowing in the coolant passage 17 (see FIG. 2).
by the way,
(1) Since the spacer body 38 is inserted into the cooling water passage 17 through the spacer mounting hole 20 of the passage wall 18 in a state before expansion, the spacer body 38 can be easily inserted.
(2) Since the spacer main body 38 expands into a predetermined shape by the engine cooling water, the spacer main body 38 having a predetermined shape can be provided in the cooling water passage 17 without requiring a special operation.
(3) By attaching the support body 32 to the passage wall 18, the spacer body 38 can be easily positioned at a predetermined position in the cooling water passage 17.
Therefore, the assembling property of the spacer 30 with respect to the cylinder head 10 can be improved by the synergistic action of the above (1) to (3).

  Further, as shown in FIG. 2, the spacer mounting hole 20 of the passage wall 18 is sealed by the expansion of the spacer main body 38 of the spacer 30, so that a dedicated part or a set of parts for sealing the spacer mounting hole 20 is used. Man-hours can be omitted.

  Further, as shown in FIG. 2, the support 32 of the spacer 30 is attached to the passage wall 18 by press-fitting the passage wall 18 into the spacer mounting hole 20, so that the support 32 is attached to the passage wall 18. Dedicated parts and the number of assembling steps can be omitted.

  Further, as shown in FIG. 3, the spacer main body 38 can be supported by a simple operation of sandwiching the support 32 by the locking piece 35.

  The present invention is not limited to the above-described embodiments, and modifications can be made without departing from the gist of the present invention. For example, the present invention is not limited to four cylinders, but can be applied to a cylinder head of an engine having one to three cylinders or five or more cylinders. Further, the number of the intake port 12 and the exhaust port 14 of the cylinder head 10 per cylinder can be appropriately increased or decreased. Further, the arrangement form such as the arrangement position, shape, size, and number of the spacers 30 is not limited to that of the above-described embodiment, and can be appropriately changed. In addition, the spacer 30 is constituted by two parts of the support body 32 and the spacer main body 38, but it is conceivable that the spacer 30 is constituted by one part or a combination of three or more parts. The spacer body 38 is made of an elastic material that expands with engine cooling water. However, the spacer main body 38 can be made of a material that does not expand with engine cooling water or a material that does not have elasticity. Further, for attaching the spacer main body 38 to the support body 32, for example, attachment means such as screwing, adhesion, engagement or the like can be employed instead of the locking piece 35. Further, for the attachment of the support body 32 to the cylinder head 10, for example, attachment means such as screwing, adhesion, engagement or the like can be employed instead of press-fitting. Further, the support 32 can be formed of a resin molded product instead of the press molded product. Further, although the spacer mounting hole 20 of the cylinder head 10 is formed of a sand mold, it can be formed by drilling after the cylinder head 10 is cast. Further, the water hole 19 formed by the sand mold of the cylinder head 10 can be used as the spacer mounting hole 20. Further, the spacer mounting hole 20 of the cylinder head 10 is not limited to the passage wall 18 on the lower surface side of the cylinder head 10 and can be provided at an appropriate position as long as it is a passage wall of the cooling water passage 17. Further, although the spacer mounting hole 20 of the passage wall 18 is sealed by the expansion of the spacer body 38, it is conceivable to seal between the support 32 and the spacer mounting hole 20 by a sealing member such as an O (O) ring.

It is a bottom view which shows the cylinder head concerning one Example of this invention. It is principal part sectional drawing which shows the attachment state of a spacer. It is principal part sectional drawing which shows the state before attachment of a spacer. It is a perspective view of a spacer. It is a bottom view which shows a cylinder head without a spacer. It is a graph which shows the analysis result of the heat transfer coefficient of a cylinder head.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Cylinder head 12 Intake port 14 Exhaust port 17 Cooling water passage 18 Passage wall 20 Spacer attachment hole (hole which penetrates a passage wall)
30 Spacer 32 Support 38 Spacer Body

Claims (6)

A cylinder head having a coolant passage through which engine coolant flows,
The cylinder head is provided with a spacer that is inserted into a hole penetrating the passage wall of the cooling water passage and adjusts the flow of the engine cooling water. The cylinder head according to claim 1,
The cylinder head, wherein the spacer is inserted into a cooling water passage on an intake side of the cooling water passage. The cylinder head according to claim 1 or 2,
The spacer has a characteristic of being expanded by the engine cooling water and is inserted into the cooling water passage through a hole in the passage wall in a state before expansion, and supports the spacer main body and the passage wall. And a support body mounted on the cylinder head. The cylinder head according to claim 3,
A cylinder head characterized in that a hole in the passage wall is sealed by expansion of the spacer body. The cylinder head according to claim 3 or 4,
The cylinder head according to claim 1, wherein the support body is attached to the passage wall by press-fitting into the hole of the passage wall. The cylinder head according to any one of claims 3 to 5,
A cylinder head characterized in that the spacer main body is supported by sandwiching the support.

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