JP7429946B2 - Spacer - Google Patents

Description

The present invention relates to a spacer disposed in a cooling water passage formed in a cylinder block of an internal combustion engine so as to surround a cylinder bore.

A spacer for regulating the flow rate, flow velocity, etc. of circulating cooling water is inserted into a cooling water flow path of an internal combustion engine through an opening (see, for example, Patent Documents 1 and 2). For example, in the spacers disclosed in Patent Documents 1 and 2, when the cylinder bore side surface of the rigid support body (spacer body) made of synthetic resin or the like comes into contact with cooling water, it becomes enlarged and the cylinder bore side surface of the cooling water flow path becomes large. A porous body is attached that contacts the wall surface. The porous body that is attached to the spacer body in this way is thin before it expands, so when inserting the spacer into the cooling water flow path, it is possible to reduce the insertion resistance and insert it smoothly. , after being placed in the cooling water flow path, it becomes enlarged and can regulate the flow of cooling water.

Japanese Patent Application Publication No. 2016-128256 JP 2019-007398 Publication

By the way, the spacer as described above is integrally molded by introducing a molten resin into the mold with a porous body disposed in the mold. However, in the case where the portions of the spacer described above that regulate the flow of cooling water are set finely, the shape of the porous body tends to become complicated. The porous body is then cut out from the original fabric, but if you try to cut out a porous body with a complicated shape, a large amount of waste will be discarded, and the material yield (number of pieces) will inevitably decrease.
will decrease.

Such a problem may be solved, for example, by configuring a porous body from a plurality of members having relatively simple shapes, as disclosed in Patent Document 2. However, if the porous body is simply composed of a plurality of members, when molten resin is introduced in the above-mentioned manufacturing process, there is no path for the molten resin to pass through the edges of the porous body and reach the region of the porous body. When the molten resin follows the path, the molten resin directly presses the edge of the porous body. This may cause the porous body to be misaligned, or the molten resin may flow around to the exposed surface side through the boundaries of the plurality of members. Such a phenomenon is extremely undesirable because it significantly deteriorates the quality of the spacer product.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a spacer with improved material yield and quality.

In order to achieve the above object, the present invention adopts the following technical means. First, the present invention is based on a spacer disposed in a cooling water passage formed in a cylinder block of an internal combustion engine so as to surround a cylinder bore. The spacer according to the present invention includes a support made of resin, a first porous body, a resin introduction part, and a second porous body. The first porous body is attached to the support. The resin introduction part is provided at a position opposite to the side to which the first porous body is attached to the support body and overlaps with the first porous body. The resin introduction part is a part where molten resin is introduced during injection molding of the support. The second porous body is attached to the support body while forming an overlapping portion with the support body in which the first porous body is interposed. In the above configuration, in the spacer according to the present invention, the edge of the second porous body at the overlapping portion is surrounded by the first porous body when viewed from the exposed surface side of the second porous body.

In this spacer, when molten resin is introduced from the gate of the mold corresponding to the resin introduction part during injection molding of the support, the molten resin flows from the region of the first porous body to the region of the second porous body. . At this time, since the molten resin flows into the area of the second porous body without passing through the edge of the second porous body, it is possible to suppress the molten resin from directly pressing the edge of the second porous body. . therefore,
It is possible to prevent the position of the second porous body from shifting due to the resin pressure of the molten resin and to prevent the molten resin from wrapping around the exposed surface of the second porous body, and it is possible to improve the quality of the spacer provided with the porous body. .

In this spacer, a configuration can be adopted in which the resin introduction part is provided in line with the overlapping part of the second porous body when viewed from the exposed surface side of the second porous body. With this configuration, the molten resin injected from the introduction site easily flows into the region of the second porous body without passing through the outer peripheral edge of the second porous body. Therefore, it is possible to suppress the position of the second porous body from shifting and the molten resin from entering the exposed surface of the second porous body.

In the spacer described above, when viewed from the exposed surface side of the second porous body, the entire one end of the second porous body constitutes an overlapping part, and the second porous body other than the overlapping part forms the second porous body. It is also possible to adopt a configuration in which the resin introduction part is within a range between an intersection point where the outer peripheral edge of the mass body and the edge of the first porous body intersect, and an imaginary line connecting the resin introduction part. With this configuration, it is possible to further suppress the outer peripheral edge of the second porous body other than the overlapping portion from being pressed by the molten resin introduced from the introduction site.

In the above spacer, it is also possible to employ a configuration in which one second porous body is attached to a plurality of mutually independent first porous bodies. With this configuration, even if the required shape of the mounting area of the porous body is complicated, for example, by dividing the first porous body and the second porous body with relatively simple shapes, the first porous body And the yield when cutting out the second porous body from the original fabric can be further improved.

When the above spacer is applied to a cylinder block having a plurality of cylinder bores, the support body may be configured to include a plurality of circular arc portions corresponding to each cylinder bore, and a connecting portion connecting adjacent circular arc portions. can. In this case, a configuration may be adopted in which the first porous body is attached to a support body corresponding to each of the plurality of circular arc parts, and the second porous body is attached to a support body corresponding to the connection part. can. With this configuration, the first porous body can be formed in the shape required for the cylinder bore, and the second porous body can be formed in the shape required for the region between the cylinder bores. That is, by forming the first porous body and the second porous body into shapes that are desirable for each part of the cylinder block, the functions of the first porous body and the second porous body can be fully exhibited.

In the above configuration, the first porous body and the second porous body may have a characteristic of expanding in size when a predetermined external factor is added. In this configuration,
Since the spacer can be placed in the cooling water flow path while the first porous body and the second porous body are compressed, the spacer can be smoothly placed without interfering with the side walls of the cooling water flow path.
In addition, even if the overlapping part of the second porous body is not fixed to the support during restoration, it is surrounded by the part of the first porous body and the part of the second porous body that are fixed to the support, so cooling water Because they are not directly exposed to water pressure, they are less likely to be damaged.

According to the present invention, it is possible to provide a spacer with improved material yield and quality.

FIG. 1 is a perspective view schematically showing an example of a spacer according to an embodiment of the present invention. FIG. 1 is a cross-sectional view schematically showing an example of a spacer according to an embodiment of the present invention. (a) is a front view (view from the porous body side) schematically showing an example of a spacer according to an embodiment of the present invention, and (b) is a diagram of a spacer according to an embodiment of the present invention. FIG. 2 is a rear view (viewed from the support side) schematically showing an example. (a) is a rear view schematically showing the flow of molten resin when manufacturing a spacer according to an embodiment of the present invention, and (b) is a rear view when manufacturing a spacer according to a configuration where defects are likely to occur. FIG. 3 is a rear view schematically showing the flow of molten resin. FIG. 3 is a vertical cross-sectional view schematically showing the state of the overlapping portion in the used state of the spacer according to the embodiment of the present invention. (a) shows the state before the porous body expands, and (b) shows the state after the porous body expands. (a) to (c) are diagrams schematically showing the positional relationship among a first porous body, a second porous body, and a resin introduction part in a spacer according to an embodiment of the present invention. It is a figure which shows typically the positional relationship of the 1st porous body, the 2nd porous body, and the resin introduction part in the spacer based on one Embodiment of this invention. It is a figure which shows typically the positional relationship of the 1st porous body, the 2nd porous body, and the resin introduction part in the spacer based on one Embodiment of this invention. It is a figure which shows typically the positional relationship of the 1st porous body, the 2nd porous body, and the resin introduction part in the spacer based on one Embodiment of this invention. (a) to (c) are diagrams schematically showing the positional relationship among a first porous body, a second porous body, and a resin introduction part in a spacer according to an embodiment of the present invention.

Embodiments of the present invention will be described in more detail below with reference to the drawings. Figure 1 shows
FIG. 2 is a perspective view schematically showing an example of a spacer in an embodiment of the present invention. FIG. 2 is a cross-sectional view schematically showing an example of a spacer in an embodiment of the present invention. FIG. 2 corresponds to a cross-sectional view of the spacer shown in FIG. Moreover, FIGS. 3A and 3B are a front view and a rear view schematically showing an example of a spacer according to an embodiment of the present invention. As will be described in detail below, in the spacer of this embodiment, the first porous body and the second porous body are arranged on one side of the support. Here, the surface of the spacer on which the first porous body and the second porous body are arranged is defined as the front surface. In this embodiment, for the sake of explanation, a spacer is illustrated as an example of a cylinder block in which two cylinder bores are arranged in series, and a spacer is arranged in an open deck type groove-shaped cooling water flow path arranged around the cylinder bore. ing. Further, in this specification, in the spacer, the direction corresponding to the axial direction of the cylinder bores is referred to as the vertical direction, and the direction corresponding to the arrangement direction of the cylinder bores is referred to as the left-right direction.

As shown in FIGS. 1, 2, and 3, the spacer 1 of this embodiment includes a support 2 made of resin, a plurality (two) of first porous bodies 3 and second porous bodies attached to the support 2. It has a mass body 4. The support body 2 includes two circular arc parts 21 each forming a partial cylindrical surface, and a connecting part 22 that connects the two adjacent circular arc parts 21. This shape is a shape that matches the cooling water flow path provided in the above-mentioned cylinder block, and the concave side of the circular arc portion 21 (hereinafter referred to as the concave surface portion 21a) is arranged in the above-mentioned cooling water flow path in a state facing the cylinder bore. be done. In addition, connection part 2
2 (hereinafter referred to as the convex surface portion 22a) is arranged in the above-mentioned cooling water flow path in a state where the convex surface side of the cylinder block (hereinafter referred to as the convex surface portion 22a) faces the cylinder block between the cylinder bores arranged in series (the region between the cylinder bores). In this embodiment, the two spacers 1 are connected in such a manner that the concave curved surfaces 21a and the convex curved surfaces 22a of each spacer 1 face each other, thereby corresponding to the overall shape of the cooling water flow path of the cylinder block. The shape is constructed. The two connected spacers 1 are arranged in the cooling water flow path of the cylinder block.

The first porous body 3 and the second porous body 4 are attached to one side of the support body 2. The second porous body 4 is attached to the support body 2 so as to form an overlapping portion 41 between the second porous body 4 and the support body 2 in which the first porous body 3 is interposed. The overlapping portion 41 of the second porous body 4 is arranged closer to the surface (the above-mentioned front side) than the first porous body 3 . Therefore, the overlapping portion 41 of the second porous body 4 is
The first porous body 3 is partially covered. Further, when viewed from the exposed surface side (the above-mentioned front side) of the second porous body 4, the edges 41a, 41b, and 41c of the overlapping portion 41 are surrounded by the first porous body 3. Note that the edges 41a, 41b, and 41c of the overlapping portion 41 are in contact with the first porous body 3.

Although not particularly limited, in this embodiment, the first porous body 3 and the second porous body 4 are both composed of porous bodies made of rectangular sheet members. Each first porous body 3 is attached to the support body 2 in a state that covers a part of each concave curved surface 21a other than the convex curved surface 22a. Further, the second porous body 4 covers a part of the convex curved surface 22a in the vertical direction, and the left end and right end of the first porous body 4 are disposed on each concave curved surface 21a. It is attached to the support body 2 in a state where it overlaps with 3. Here, in the axial direction (vertical direction) of the partial cylindrical surface constituting the concave curved surface 21a, the length of the second porous body 4 is smaller than the length of the first porous body 3; The entirety of each of both end portions of the body 4 constitutes an overlapping portion 41 that overlaps each first porous body 3 . In this embodiment, the second porous body 4 is arranged approximately at the center of the first porous body 3 in the vertical direction. Therefore, as described above, the edges 41a, 41b, 41c of the overlapping portion 41 are surrounded by the first porous body 3 when viewed from the exposed surface side of the second porous body 4. Note that the edge 41a is an edge along the vertical direction, and the edges 41b and 41c are edges along the left-right direction.

In the above configuration, the material of the resin forming the support body 2 is not particularly limited as long as injection molding is possible. For example, hard synthetic resin such as polyamide can be used. Also,
The materials constituting the first porous body 3 and the second porous body 4 are not particularly limited as long as they can regulate the cooling water flow path integrally with the support body 2 within the above-mentioned cooling water flow path. For example, cellulose sponges, water-swellable sponges, water-soluble binders, or binders that dissolve or melt at a temperature higher than a predetermined temperature are used to maintain a compressed state, and when a predetermined external factor is added, a huge amount of Materials such as foams or non-foamed porous bodies that have the property of forming a foam can be used.

Although it is not essential that the material of the first porous body 3 and the material of the second porous body 4 be the same,
In this embodiment, compressed cellulose sponge is used as a particularly suitable material for the first porous body 3 and the second porous body 4. The cellulosic sponge is maintained in a compressed state. When the compressed cellulose sponge comes into contact with water,
Contact with water adds an external factor, and the addition of the external factor causes the material to expand to its uncompressed state. More specifically, cellulose sponge is a natural material made of cellulose derived from pulp and natural fibers (eg, cotton, etc.) added as reinforcing fibers. Cellulose has a hydrophilic group (OH) and has the property of being chemically compatible with water. In addition, cellulose sponge is a porous material, and when dried under pressure, hydrogen bonds between cellulose molecules create a compressed state, while when exposed to moisture from this state, water molecules It has the property of dissociating hydrogen bonds between molecules and restoring it from a compressed state.

In this embodiment, the first porous body 3 and the second porous body 4 are integrated with the support body 2 by insert molding. That is, the first porous body 3 and the second porous body 4 which are individually compressed are prepared, and while they are placed in a mold for molding the spacer 1, the support body 2 is placed in the mold. A molten resin is introduced. In the portion where the first porous body 3 or the second porous body 4 and the support body 2 are in direct contact, the molten resin impregnates the first porous body 3 or the second porous body 4. , the first porous body 3 and the second porous body 4 are fixed to the support body 2. On the other hand, the portion of the second porous body 4 that is not in direct contact with the support body 2, that is, the overlapping portion 41 of the second porous body 4 is not fixed to the support body 2. However, the overlapping portion 4 of the second porous body 4
1 is a region of the first porous body 3 on which the overlapping part 41 is overlapped, together with the covering part 32, under the pressure of the molten resin constituting the support body 2, the overlapping part 41 of the second porous body 4 and the second porous body 3 are 1 and the covering portion 32 of the porous body 3 are attached to each other by hydrogen bonding (see FIG. 2). As a result, the first porous body 3 and the second porous body 4 can be handled as an integral member.

The above-mentioned molten resin is injected from the gate of the mold. As a result, a resin introduction part 5, which is a part for introducing molten resin, is formed in the support body 2 at a position corresponding to the gate of the mold. The resin introducing portion 5 is provided at a position opposite to the side on which the first porous body 3 is attached to the support body 2 and overlaps with the first porous body 3 . In addition, in the front view shown in FIG. 3(a), the second porous body 4 is present on the front side of the first porous body 3 in the figure, but in order to facilitate understanding of the positional relationship, the second porous body 4 is The edge 31 of the first porous body 3 covered by the second porous body 4 is shown by a broken line. In addition, in the rear view shown in FIG. 3(b), only the support body 2 is visible, and the first support body 2 is visible.
The porous body 3 and the second porous body 4 will be present on opposite sides of the support body 2, but in order to make it easier to understand the positional relationship, the first porous body fixed to the support body 2 will be The edge of the solid body 3 and the edge of the second porous body 4 are shown by broken lines, and the second porous body 4 is located further back in the figure than the first porous body 3.
The edges 41a, 41b, and 41c are shown by dashed lines.

In addition, as shown in FIG. 3(b), in this embodiment, as a more preferable form, the resin introduction part 5 is located at a different position from the overlap part 41 (overlap part The overlapping portion 41 is provided in a position that does not overlap with the overlapping portion 41). In this embodiment,
In particular, in order to make the moving distance of the injected molten resin uniform, the resin introduction part 5 is located at the top 22b of the convex curved surface 22a of the connecting part 22 (the most protruding part of the convex curved surface 22a) in FIG.
It is set at the center position of the distance from to the far end 22c of the arcuate portion 21 in the left-right direction. Further, the second porous body 4 other than the overlapping portion 41 is connected to an intersection 52 where the outer peripheral edge 42 of the second porous body 4 and the edge 31 of the first porous body 3 intersect, and the resin introduction portion 5 (resin It is formed so as to fit within a range sandwiched by a virtual line 51 (indicated by a two-dot chain line in the figure) connecting the center of the introduction part 5. The outer peripheral edge 42 of the second porous body 4 is formed into a straight line with a slope smaller than the slope of the imaginary line 51. Here, a straight line with a slope smaller than the slope of the virtual line 51 means a straight line that is closer to the slope of a straight line along the left-right direction than the slope of the virtual line 51. Further, the outer peripheral edge 42 of the second porous body 4 is an outer peripheral portion of the second porous body 42 that extends from the intersection 52 to the outside of the overlapping portion 41 . Figure 3(b)
In the embodiment shown in , the outer peripheral edge 42 of the second porous body 4 is formed in a straight line along the left-right direction.

Here, the flow of the molten resin when manufacturing the spacer 1 will be explained. FIG. 4A is a rear view schematically showing the flow of molten resin during manufacture of the spacer 1. FIG. Further, FIG. 4(b) is a rear view schematically showing the flow of molten resin during manufacture of a spacer (comparative example) having a configuration in which defects are likely to occur. Note that in FIG. 4(a), the dashed line shown in FIG. 3(b) is omitted.

As shown in FIG. 4(a), in the spacer 1 of this embodiment, when molten resin is injected from the gate of the mold corresponding to the resin introduction part 5, the injected molten resin spreads inside the mold. go. As described above, in the spacer 1 of this embodiment, the resin introduction part 5 is provided at a position overlapping with the first porous body 3, so the injected molten resin is placed at a position facing the gate of the mold. After colliding with the existing first porous body 3, it spreads radially from the gate along the back surface of the first porous body 3.

Further, as described above, the covering portion 32 of the first porous body 3 is interposed between the overlapping portion 41 of the second porous body 4 and the support body 2. Therefore, as shown in FIG. 4(a), the first porous body 3
The edge 41a of the second porous body 4 is placed on the side on which the molten resin advances (the back surface of the first porous body 3),
41b and 41c (see FIGS. 3(a) and 3(b)) do not exist. Therefore, the molten resin spreads smoothly within the mold without colliding with the edges 41a, 41b, 41c of the second porous body 4.

On the other hand, in the spacer 20 of the comparative example shown in FIG. 4(b), the order in which the ends of the second porous body 4 and the first porous body 3 overlap is reversed. That is, the structure is such that the end portion of the second porous body 4 is interposed between the first porous body 3 and the support body 2.

In such a configuration, when the molten resin is injected from the gate of the mold corresponding to the resin introduction part 5, the injected molten resin is injected into the first porous body, as in the case shown in FIG. 4(a). 3, it spreads radially from the gate along the back surface of the first porous body 3.

However, in the comparative example, in the portion where the first porous body 3 and the second porous body 4 overlap, the end of the second porous body 4 is interposed between the first porous body 3 and the support body 2. Therefore, Figure 4 (
As shown in b), the edges 41a, 41b, 41c of the second porous body 4 are exposed on the surface of the first porous body 3 on the side where the molten resin advances. Therefore, the molten resin collides with at least the edge 41a of the second porous body 4 (in FIG. 4(b), the edge 41a is shown by a thick line). If such a collision occurs, the position of the second porous body 4 may shift, or the second porous body 4 and the first porous body may As a result of the molten resin entering between the second porous body 3 and the second porous body 3, the molten resin may enter the exposed surface side of the second porous body 4. If such a phenomenon occurs, the quality of the spacer 20 will be significantly degraded.

On the other hand, in the spacer 1 of this embodiment, the second porous body 4 is
Since the molten resin flows into the region of the second porous body 4 without passing through the edges 41a, 41b, 41c of the second porous body 4, it is possible to suppress the molten resin from directly pressing the edges 41a, 41b, 41c of the second porous body 4. .
Therefore, it is possible to prevent the position of the second porous body 4 from shifting due to the resin pressure of the molten resin and to prevent the molten resin from wrapping around the exposed surface of the second porous body 4, thereby improving the quality of the spacer provided with the porous body. can be done. Further, when the molten resin is injected from the resin introduction part 5, it flows from the back side of the first porous body 3 to the back side of the second porous body 4. At this time, once the molten resin is
After exiting from the back area of the second porous body 4 via the outer circumferential edge 42 of the second porous body 4, the second porous body passes through the outer circumferential edge 42 of the second porous body 4 again. The risk of it returning to the back side of No. 4 is low. Therefore, the outer peripheral edge 42 of the second porous body 4 is prevented from being pressed by the molten resin.

In addition, in the spacer 1 of the present embodiment, the resin introduction part 5 is arranged in line with the overlapping part 41 when viewed from the exposed surface side of the second porous body 4, so that the molten resin is is the second
It is easier to face the back surface of the second porous body 4 without passing through the outer peripheral edge 42 of the porous body 4. Therefore, it is possible to further suppress the position of the second porous body 4 from shifting and the molten resin from entering the exposed surface of the second porous body 4.

Furthermore, since the overall shape of the porous body fixed to the support body 2 is realized by using a plurality of porous bodies having different shapes, such as the first porous body 3 and the second porous body 4, the entire shape of the porous body is realized. The shapes of the first porous body 3 and the second porous body 4 can be made simpler than when they are formed from one porous body. Therefore, it is possible to reduce the amount of waste when cutting out the porous material from the original fabric.
Material yield (number of pieces) can be improved. In particular, when adopting a configuration in which one second porous body 4 is attached to a plurality of mutually independent first porous bodies 3, the required shape of the attachment area of the porous body may be complicated. , the first porous body 3 and the second porous body 3 have a simpler shape.
The porous body 4 can be divided into two parts. As a result, the yield when cutting out the first porous body 3 and the second porous body 4 from the original fabric can be further improved.

The spacer 1 as described above is inserted into the cooling water flow path in the cylinder block through its opening. FIGS. 5A and 5B are vertical cross-sectional views schematically showing the state of the overlapping portion 41 when the spacer 1 according to an embodiment of the present invention is in use. Furthermore, Figure 5
(a) and FIG. 5(b) are partial vertical cross-sectional views taken along a plane that includes the central axis of the cylinder bore of the cylinder block and passes through the overlapping portion 41 of the second porous body 4 included in the spacer 1.

FIG. 5A shows a state in which the spacer 1 is arranged in the cooling water flow path 6 of the cylinder block 10. As shown in FIG. 5(a), the spacer 1 is arranged in the cooling water flow path 6 with the first porous body 3 and the second porous body 4 facing the cylinder bore 11. Spacer 1 is
It is disposed within the cooling water flow path 6 through the opening 61 of the cooling water flow path 6 . At this time, since the first porous body 3 and the second porous body 4 are maintained in a compressed state, the first porous body 3 and the second porous body 4 are inside the cooling water flow path 6 on the cylinder bore 11 side. It is difficult to interfere with the inner wall portion 6a and can be inserted smoothly. As shown in FIG. 5(b), the cylinder head 12 is fastened and integrated with the upper surface of the cylinder block 10 via the head gasket 13, and then the cooling water 14 is introduced into the cooling water passage 6 from a cooling water inlet (not shown). will be introduced.

As described above, when the cooling water 14 is introduced into the cooling water flow path 6, the cooling water 14 comes into contact with the first porous body 3 and the second porous body 4 made of cellulose sponge, and The body 3 and the second porous body 4 expand toward the cylinder bore 11 side. As the first porous body 3 and the second porous body 4 expand, the exposed surface (the surface opposite to the support body 2) 4a of the overlapping portion 41 of the second porous body 4
comes into contact with the inner inner wall surface 6a of the cooling water flow path 6. In addition, the exposed surface of the first porous body 3 (the support body 2
3a on the opposite side contacts the inner wall surface 6a of the cooling water flow path 6. At this time, Fig. 5(b)
As shown in FIG. 2 , the overlapping portion 41 of the second porous body 4 is surrounded by the first porous body 3 .

As described above, the overlapping portion 41 of the second porous body 4 is not in direct contact with the support 2 and is therefore not fixed to the support 2. In the compressed state, the overlapping portion 41 of the second porous body 4 remains attached to the first porous body 3 through the hydrogen bond described above, but the cooling water flow path 6
If expansion occurs within the membrane, the adhesion caused by the hydrogen bond will also be dissolved. As a result, the second
The overlapping portion 41 of the porous body 4 becomes a free end portion that is not fixed. If the cooling water collides with such a free end, there is a possibility that the free end will be damaged and detached.

However, in the overlapping part 41 of the second porous body 4 of this embodiment, the edges 41a, 41b, 41c of the overlapping part 41 are surrounded by the first porous body 3 fixed to the support body 2, as described above. ing. In addition, in the second porous body 4, an overlapping portion 41 that is not surrounded by the first porous body 3
The other portions are directly fixed to the support 2 since the first porous body 3 is not interposed between the support 2 and the support 2. Therefore, the overlapping part 41 which becomes a free end part when expanded is surrounded by the first porous body 3 and the second porous body 4 which are fixed to the support body 2. That is, since the overlapping portion 41 of the second porous body 4 is surrounded by the portion of the first porous body 3 and the portion of the second porous body 4 fixed to the support body 2, it directly receives the water pressure of the cooling water. This makes it less likely to be damaged.

As explained above, according to the spacer 1 of the present embodiment, it is possible to suppress the molten resin from directly pressing the edge of the second porous body 4 during injection molding of the support body 2. The pressure can prevent the second porous body 4 from shifting its position and prevent the molten resin from wrapping around the exposed surface of the second porous body 4, thereby improving the quality of the spacer including the porous body.
Furthermore, since the spacer 1 of this embodiment adopts a configuration in which the first porous body 3 and the second porous body 4 are arranged partially overlapping, the shape of each porous body is simplified. As a result, the material yield can be improved compared to the case where the entire structure is made of one porous body. Furthermore, in order to attach one porous body over the concave or convex surfaces of the support, it is necessary to install one porous body over the concave or convex surfaces of the mold. However, in the spacer 1 of this embodiment, the first porous body 3 and the second porous body 4 can be installed so as to correspond to the concave surface and the convex surface, respectively. Therefore, the first porous body 3 and the second porous body 4 can be attached to the spacer having a concave surface or a convex surface while suppressing displacement of the first porous body 3 and the second porous body 4.

Then, by adopting a configuration in which the first porous body 3 is attached to the concave curved surface 21a of the circular arc portion 21 like the spacer 1, and the second porous body 4 is attached to the convex curved surface 22a of the connecting portion 22, the first The porous body 3 can be formed in the shape required for the cylinder bore, and the second porous body 4 can be formed in the shape required for the region between the cylinder bores. In other words, the functions of the first porous body 3 and the second porous body 4 can be fully exhibited by giving the first porous body 3 and the second porous body 4 a shape that is desirable for each part of the cylinder block. I can do it.

Next, based on FIGS. 6(a) to (c), FIGS. 7 to 9, and FIGS. 10(a) to (c),
Other examples of the first porous body, second porous body, and resin introduction part that can be employed in the present invention will be described. In addition, FIGS. 6(a) to (c), FIGS. 7 to 9, and FIGS. 10(a) to (c),
3(a), the spacer is viewed from the front side (the exposed surface side of the second porous body). FIG. In each figure, illustration of the support body 2 that includes the entire arrangement area of the first porous body 3 and the second porous body 4 in each figure is omitted, and the resin introduction part 5 is shown by a broken line. In addition, the same names and symbols are used for porous bodies that have different shapes but have the same functions as the first porous body 3 and the second porous body 4 of the spacer 1 described above. ing.

In the above embodiment, the form shown in FIG. 3(b) has been described as a preferable form, but the resin introduction part 5 may be set at any position as long as it overlaps with the first porous body 3. for example,
As shown in FIG. 6(a), the resin introduction part 5 may be set at a position corresponding to the center of the first porous body 3 in the vertical direction and the horizontal direction. In addition, as shown in FIG. 6(b), the resin introduction part 5
can also be set at a position that overlaps with the overlapping portion 41 as long as it overlaps with the first porous body 3 . Further, as shown in FIG. 6(c), the resin introducing portion 5 may be set at a position corresponding to the end portion of the first porous body 3 on the side opposite to the end portion where the overlapping portion 41 is located. good. Even with these configurations, the injected molten resin does not collide with the edge of the second porous body 4, so the position of the second porous body 4 is shifted as in the above embodiment. In addition, it is possible to suppress the molten resin from going around to the exposed surface of the second porous body 4.

Further, in the above embodiment, a configuration in which the overlapping portion 41 is set on the short side of the rectangular first porous body 3 has been described. the first of
It may be set on the long side of the porous body 3. Further, in the above embodiment, a configuration in which one resin introduction section 5 is provided for each first porous body 3 has been described, but the number of resin introduction sections 5 is not particularly limited, and as shown in FIG. A plurality of resin introduction portions 5 may be provided for each porous body 3. Even with such a configuration, the same effects as the spacer 1 can be obtained.

Furthermore, in the above embodiment, a configuration in which one second porous body 4 is stacked on one first porous body 3 has been described, but as shown in FIG. 8, one first porous body 3 A configuration may be adopted in which a plurality of second porous bodies 4 (three in FIG. 8) are stacked on top of each other. In addition, in this example, the resin introduction part 5 is set at a position corresponding to the vertical and horizontal center of the first porous body 3 without overlapping with the overlapping part 41 of each second porous body 4. are doing. however,
As described above, the number and position of the resin introducing portions 5 can be arbitrarily set as long as they overlap with the first porous body 3.

Further, in the above embodiment, the entire one end of the second porous body 4 is the overlapping part 41, that is, the area where the second porous body 4 and the support body 2 are in direct contact is viewed from the overlapping part 41. Although a configuration in which the second porous body 4 exists in only one direction has been described, it is not essential that the entire one end of the second porous body 4 becomes the overlapping part 41. For example, as shown in FIG. 9, the regions where the second porous body 4 and the support body 2 are in direct contact may exist in two different directions when viewed from the overlapping portion 41. Even with such a configuration, as long as the resin introducing portion 5 is set at a position overlapping the first porous body 3, the same effect as that of the spacer 1 described above can be obtained.

In addition, in the above embodiment, the first porous body 3 and the second porous body 4 are both rectangular sheets, but the first porous body 3 and the second porous body 4 are The shape is not limited to a rectangular shape. For example, as shown in FIG. 10(a), a trapezoidal sheet-like member whose width in the vertical direction gradually becomes thinner as the shape of the second porous body 4 moves away from the overlapping portion 41 is used as the second porous body 4. It can be adopted as More specifically, the second porous body 4 is formed such that the width in the vertical direction decreases as the distance from the overlapping portion 41 increases. and,
The maximum dimension w1 of the second porous body 4 in the vertical direction is set smaller than the minimum dimension w2 of the first porous body 3. In this configuration, the molten resin introduced from the introduction site flows from the back side of the first porous body 3 to the back side of the second porous body 4 and then passes through the outer peripheral edge 42 of the second porous body 4. Then, the flow toward the back side of the second porous body 4 can be reduced. Therefore, it is possible to suppress the outer peripheral edge of the second porous body 4 from being pressed by the molten resin. Also, Figure 1
0(b), as the shape of the second porous body 4 moves away from the overlapping part 41,
A semi-elliptical sheet-like member whose width in the vertical direction gradually becomes narrower can be employed as the second porous body 4.

Furthermore, as shown in FIG. 10(c), a trapezoidal sheet member whose vertical width gradually increases as the shape of the second porous body 4 moves away from the overlapping portion 41 is used as the second porous body. 4
It can be adopted as However, the entire one end of the second porous body 4 overlaps the overlapping portion 4.
1, the second porous body 4 other than the overlapping portion 41 as shown in FIG. 10(c) is
It is formed within a range between an imaginary line 51 connecting the resin introduction part 5 and an intersection 52 where the outer peripheral edge 42 of the second porous body 4 and the edge 31 of the first porous body 3 intersect. It is more preferable that In this case, it is more preferable that the outer peripheral edge 42 of the second porous body 4 is formed in a linear shape with a slope smaller than the slope of the imaginary line 51. Note that here, an example is shown in which the shape of the second porous body 4 changes continuously as it moves away from the overlapping part 41, but for example,
The second porous body 4 may have a configuration in which the width in the vertical direction changes discontinuously as the shape of the second porous body 4 moves away from the overlapping portion 41, such as in a step shape. Moreover, in the case shown in FIG. 10(c),
The edge of the first porous body 3 on the side where the overlapping portion 41 of the second porous body 4 is formed has an arc shape.

As described above, according to the present invention, it is possible to provide a spacer with improved material yield and quality.

Note that the above-described embodiments do not limit the technical scope of the present invention, and various modifications and applications other than those already described are possible within the scope of the present invention. For example, the above-mentioned cellulose sponge may be a micro-granule product with very small bubbles, a small-particle product with small bubbles, or a medium-particle product with medium-sized bubbles. . Further, the cellulose sponge is preferably made of cellulose and reinforcing fibers, but is not limited thereto, and may be made of cellulose alone. In addition to sponges made of cellulose itself, cellulose sponges include sponges made of cellulose derivatives, such as cellulose ethers and cellulose esters, in which the hydroxyl groups of cellulose are retained to the extent that they can maintain a compressed state.
Alternatively, a sponge made of a mixture of these may be selected. Furthermore, it is not excluded that the first porous body 3 and the second porous body 4 may be made of materials other than those mentioned above, as long as they are made of porous bodies.

Furthermore, the aspect of the overlapping portion of the first porous body 3 and the second porous body 4 is not limited to that exemplified in the above embodiment, and other formation aspects are also possible. Moreover, although the spacer of the present invention is applied to a two-cylinder internal combustion engine, the present invention is not limited to this and can be applied to internal combustion engines with other numbers of cylinders.

1 Spacer 2 Support 3 First porous body 4 Second porous body 5 Resin introduction part 6 Cooling water channel 10 Cylinder block 11 Cylinder bore 21 Arc part 22 Connection part 31 Edge of first porous body 41 Overlapping part 41a, 41b, 41c Edge of the second porous body at the overlapping part 42 Outer periphery 51 Virtual line 52 Intersection between the outer rim of the second porous body and the edge of the first porous body

Claims (6)

A spacer disposed in a cooling water flow path formed in a cylinder block of an internal combustion engine to surround a cylinder bore,
a support made of resin;
a first porous body attached to the support;
A resin that is provided at a position on the support body opposite to the side to which the first porous body is attached and overlaps with the first porous body, and is an introduction site for molten resin during injection molding of the support body. An introduction and
a second porous body attached to the support body so as to form an overlapping portion between the second porous body and the support body;
Equipped with
A spacer characterized in that an edge of the second porous body in the overlapping portion is surrounded by the first porous body when viewed from the exposed surface side of the second porous body. The spacer according to claim 1,
The spacer is characterized in that the resin introducing portion is provided in line with the overlapping portion when viewed from the exposed surface side of the second porous body. In the spacer according to claim 1 or claim 2,
When viewed from the exposed surface side of the second porous body, the entire one end of the second porous body constitutes the overlapping part, and the second porous body other than the overlapping part forms the second porous body. A spacer characterized by being formed within a range between an imaginary line connecting the resin introduction part and an intersection point where the outer peripheral edge of the mass body and the edge of the first porous body intersect. . The spacer according to any one of claims 1 to 3,
A spacer characterized in that one second porous body is attached to a plurality of mutually independent first porous bodies. The spacer according to any one of claims 1 to 4,
A plurality of cylinder bores are provided in the cylinder block, and
The support body includes a plurality of arcuate portions corresponding to each of the cylinder bores, and a connection portion that connects adjacent arcuate portions,
The first porous body is attached to the support body corresponding to each of the plurality of arcuate parts,
A spacer characterized in that the second porous body is attached to the support body corresponding to the connection portion. The spacer according to any one of claims 1 to 5,
The spacer is characterized in that the first porous body and the second porous body have a property of expanding in size when a predetermined external factor is added thereto.

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