JP6863576B2 - Spacer - Google Patents

Description

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

In the cooling water flow path of the internal combustion engine, a spacer for regulating the flow (flow rate, flow velocity, etc.) of the flowing cooling water is inserted and arranged through the opening (see, for example, Patent Documents 1 to 3). In the spacers (regulatory members) disclosed in Patent Documents 1 to 3, the surface of the spacer body (support) made of a rigid body such as synthetic resin on the cylinder bore side becomes enormous when it comes into contact with the cooling water, and the cooling water flow path becomes enormous. A member that comes into contact with the wall surface on the cylinder bore side of the above is attached. Since the member attached to the spacer body in this way is bulky (thin) before it becomes enormous, when inserting the spacer into the cooling water flow path, the insertion resistance is reduced to facilitate the insertion. After arranging it in the cooling water flow path, it will be enormous and the flow of cooling water will be regulated.

Japanese Unexamined Patent Publication No. 2014-194219 WO2016 / 104478 Gazette Japanese Unexamined Patent Publication No. 2016-128256

By the way, when the cylinder block has a plurality of cylinder bores, the cooling water flow path formed so as to surround the plurality of cylinder bores is provided with a constricted portion facing the cylinder bore side in the portion between the adjacent cylinder bores. Therefore, the spacer arranged in the cooling water flow path is formed with a convex portion facing the cylinder bore side corresponding to the constricted portion. In the spacer disclosed in the patent document, the enormous member is attached to the surface of the spacer body on the cylinder bore side, and in terms of insertability of the spacer into the cooling water flow path and regulation of cooling water flow. It is valid.

Then, in the process of putting the spacers shown in Patent Documents 2 and 3 into practical use, the applicant has devised to provide the porous body as the enormous member in the convex portion, and further. It was also found that the following problems occur. 8 (a) and 8 (b) are diagrams showing a state in which such a problem occurs. The spacer 102 shown in FIG. 8 is a porous body 103 having a shape inserted into the cooling water flow path 101 formed in the cylinder block 100 and a porous body integrated with the cylinder bore (see FIG. 1) side surface 103a of the spacer body 103. It is composed of a body 104. The porous body 104 is made of a cellulosic sponge similar to the example shown in Patent Document 2 or Patent Document 3. In FIG. 8, the spacer main body 103 has a convex curved portion 103b at a position corresponding to the inter-bore portion (see FIG. 1) of the cooling water flow path 101, and the porous body 104 has a convex curved surface of the convex curved portion 103b. It is integrally attached to the cylinder bore side surface 103a of the spacer body 103 including the spacer body 103. FIG. 8A shows a state in which the spacer 102 in which the spacer main body 103 and the porous body 104 maintained in the compressed state are integrated is arranged in the cooling water flow path 101 of the cylinder block 100. Further, FIG. 8B shows a state in which the cooling water is introduced into the cooling water flow path 101 and the porous body 104 is restored to the state before compression by coming into contact with the cooling water.

As shown in FIG. 8 (b), when the porous body 104 comes into contact with the cooling water, it tends to restore to the state before compression. In FIG. 8B, the arrows a1 and a2 indicate the restoration direction of the porous body 104, which is the direction facing the compression direction of the porous body 104. More specifically, the porous body 104 is restored in the direction a1 toward the center of curvature (center of the cylinder bore) of the curved surface portion in the curved surface portion other than the convex curved surface portion of the convex curved surface portion 103b, and the convex portion 103b is convex. The curved surface portion is restored in the direction a2 toward which the top of the convex curved portion 103b faces. By this restoration, the porous body 104 on the curved surface portion other than the convex curved surface portion of the convex curved portion 103b comes into contact with the cylinder bore side wall surface (inner inner wall surface) 101a of the cooling water flow path 101. However, in the portion of the porous body 104 corresponding to the convex curved portion 103b, the surface length in the direction indicated by the arrow b needs to be increased after restoration. Therefore, when the elongation performance of the porous body is low, the porous portion of this portion is porous. The body 104 is not sufficiently restored in the restoration direction a2. As a result, a gap is formed between the porous body 104 in the convex portion 103b and the cylinder bore side wall surface 101a of the cooling water flow path 101, and the cooling water flowing through this portion cannot be sufficiently regulated.

The present invention has been made in view of the above, and provides a novel spacer capable of increasing the amount of the compressed porous body provided in the portion including the convex portion of the support to be restored at the convex portion. The purpose is.

The spacer according to the present invention is a spacer arranged in a cooling water flow path formed in a cylinder block of an internal combustion engine so as to surround a cylinder bore, and is a support made of a rigid material having a convex portion and the support. The porous body is attached to the side surface including the convex curved surface of the convex portion in the above, and the porous body is maintained in a compressed state, and when a predetermined external factor is added, the porous body before compression is provided. It has the property of restoring to a state, and is characterized in that a slit that opens on the side opposite to the support is formed in a portion of the porous body corresponding to the convex portion.

When the porous body attached to the convex portion of the support has a low elongation performance when the porous body is restored, this becomes an inhibitory factor, and the porous body in the convex portion becomes The original restoration will not be done sufficiently. However, according to the spacer according to the present invention, since the porous body in this portion is provided with a slit, the insufficient elongation of the porous body is compensated for by increasing the opening width of the slit. Therefore, even if the elongation performance of the porous body is low, the influence thereof is alleviated, and the amount of restoration of the porous body in this portion from the compressed state to the state before compression is increased.

In the spacer according to the present invention, the slit is formed so as to extend in the depth direction of the cooling water flow path, and the length of the slit along the depth direction of the cooling water flow path is the length of the porous body. It may be formed so as to be shorter than the length along the depth direction of the cooling water flow path.
According to this, since the slit does not extend to the entire depth direction of the porous body, there is less concern that the porous body will rupture starting from the slit when handling such as when integrating the porous body with the support. can do.

In the spacer according to the present invention, a plurality of the slits may be formed in the depth direction of the cooling water flow path and in the circumferential direction of the cooling water flow path.
According to this, due to the plurality of slits formed in the depth direction and the circumferential direction, the total width of the slit openings is substantially increased, and the porous body in the portion corresponding to the convex portion is in a compressed state. It is possible to more effectively increase the amount of restoration when restoring from the state before compression.

In the spacer according to the present invention, the support may be made of a hard synthetic resin, integrally molded with the porous body, and the slit may have a shape that does not open to the support side. ..
According to this, when the support and the porous body are integrally molded, the resin which is the material of the support does not flow into the slit, so that the effect of increasing the restoration amount by the slit is maintained.

In the spacer according to the present invention, the porous body is made of a cellulosic sponge in a compressed state, and the addition of the external factor may be that moisture comes into contact with the cellulosic sponge.
According to this, in the case of a cellulosic sponge having low elongation performance, the effect of increasing the restoration amount by the slit is more preferably exhibited.

In the spacer according to the present invention, a plurality of the cylinder bores may be arranged, and the convex portion may have a shape protruding toward a portion between adjacent silin bores.
According to this, it is possible to improve the function of the porous body that regulates the flow of the cooling water in the portion between the cylinder bores in the cooling water flow path.

According to the spacer according to the present invention, it is possible to increase the amount of the compressed porous body provided in the portion including the convex portion of the support to be restored at the convex portion.

It is a 1st embodiment of the spacer which concerns on this invention, and is the schematic cross-sectional plan view which shows the state which the spacer is arranged in the cooling water flow path of an internal combustion engine. (A) is an enlarged view of part X of FIG. 1, and (b) shows a state in which the cooling water comes into contact with the porous body from the state of (a) and the porous body is restored to the state before compression ( It is the same figure as a). (A) is a cross-sectional view taken along the line YY in FIG. 1, and (b) is a state in which the cooling water comes into contact with the porous body from the state of (a) and the porous body is restored to the state before compression. It is the same figure as (a) which shows. (A) is a view of a portion including the convex portion of the spacer of the same embodiment as viewed from the cylinder bore side, and (b) and (c) are similar views showing a modified example thereof. (A) and (b) are the same as FIG. 4 (a) showing other modified examples. It is the same figure as FIG. 1 which shows the 2nd Embodiment of the spacer which concerns on this invention. It is a figure which shows the 3rd Embodiment of the spacer which concerns on this invention, and is a partially enlarged view of the state which the porous body is enormous like the figure of FIG. 1 of the main part. (A) and (b) show a conventional spacer in which a porous body is attached to a convex portion of a support, and (a) shows a convex portion indicating a state in which the spacer is arranged in a cooling water flow path of an internal combustion engine. It is a cross-sectional view of a portion including the portion, and (b) is the same view as (a) showing a state in which the cooling water comes into contact with the porous body from the state of (a) and the porous body is restored to the state before compression. is there.

Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 to 7. 1 to 5 show a first embodiment of the spacer according to the present invention, and FIG. 1 shows a state in which the spacer of the same embodiment is inserted into the cooling water flow path 3 of the cylinder block 1 in the internal combustion engine 10. Shown. The cylinder block 1 shown in FIG. 1 constitutes a three-cylinder automobile engine (internal combustion engine) 10, and is provided so that three cylinder bores (cylinders) 2 ... Are connected in series in an adjacent state. Reference numeral 1a is a bolt (not shown) insertion hole for uniting and fastening the cylinder head 9 to the cylinder block 1 via the head gasket 9a (see FIG. 3B). An open deck type groove-shaped cooling water flow path 3 is formed in a series around the three cylinder bores 2 ... A cooling water introduction port 4 and a cooling water outlet port 5 leading to the cooling water flow path 3 are provided at appropriate positions in the cylinder block 1. The cooling water outlet 5 is connected to a radiator (not shown) by piping, and the outlet side of the radiator is connected to the cooling water introduction port 4 via a water pump (not shown). As a result, the cooling water (including the antifreeze liquid) is configured to circulate between the cooling water flow path 3 and the radiator. When the cylinder head 9 is also provided with a cooling water flow path (not shown), the cooling water flow path 3 of the cylinder block 1 and the cooling water flow path of the cylinder head 9 are configured to communicate with each other. In this case, the cylinder block 1 does not have to have the cooling water outlet, and the cylinder head 9 is provided with a cooling water outlet, to which a pipe leading to the radiator is connected.

The cooling water flow path 3 has an arc-shaped portion 3a ... Formed so as to surround the cylinder bore 2 and a constricted-shaped portion 3b ... Formed so as to be close to each other and form a pair with the portions between the adjacent cylinder bores 2 and 2. ing. The groove width of the constricted portion 3b ... Is larger than the groove width of the other arc-shaped portion 3a of the cooling water flow path 3. The inner wall surfaces of the cooling water flow path 3 are the inner wall surface (inner inner wall surface) 3c on the cylinder bore 2 side formed so as to correspond to the arc-shaped portion 3a ... And the constricted shape portion 3b, and the side opposite to the cylinder bore 2. It is composed of the inner wall surface (outer inner wall surface) 3d of the above. A piston 20 that reciprocates along the axial direction is provided in each cylinder bore 2, and the piston 20 slides on the inner peripheral surface 2aa of the cylinder bore wall 2a via a piston ring 20a attached to the outer peripheral portion thereof. It is configured to get. The circumferential direction d of the cooling water flow path 3 in the present embodiment is a direction based on the ring shape surrounding the cylinder bore 2 ... in a plan view of the cylinder bore 2 ... The depth direction c of the cooling water flow path 3 is orthogonal to the circumferential direction d of the cooling water flow path 3 and is a direction along the central axis of each cylinder bore 2 ...

The spacer 6 of the present embodiment is a spacer arranged in the cooling water flow path 3, and has a support 7 made of a rigid material having a convex portion 71 and a convex curved surface 71a of the convex portion 71 in the support 7. It includes a porous body 8 attached to the side surface 7a including the surface. The porous body 8 is made of a material having a property of being maintained in a compressed state and being restored to a state before compression when a predetermined external factor is added. A slit 81 that opens on the opposite side of the support 7 is formed in the curved portion 8b corresponding to the convex portion 71 of the support 7 in the porous body 8. The support 7 in the present embodiment is made of a molded body of a rigid synthetic resin (made of a rigid material) having a tubular shape corresponding to the overall shape of the cooling water flow path 3, and corresponds to the constricted shape portion 3b of the cooling water flow path 3. A convex curved portion 71 ... Protruding toward a portion between the cylinder bores 2 and 2 is provided in the portion to be formed. The porous body 8 is integrally fixed to the side surface (inner surface) 7a on the cylinder bore 2 side including the convex curved surface 71a of the convex curved portion 71 ... That is, the porous body 81 is fixed so as to cover a part of the convex curved surface 71a of the convex curved portion 71. The slit 81 is formed in the curved portion 8b corresponding to the convex portion 71 in the porous body 8 and is formed so as to extend in the depth direction c (see FIG. 3A) of the cooling water flow path 3. .. The curved portion 8b of the porous body 8 is formed along the convex portion 71 of the support 7, and the side surface on the cylinder bore 2 side is formed on a curved surface having a larger radius of curvature than the side surface on the support 7 side. .. More specifically, the slit 81 is located at a position corresponding to the center of the convex portion 71 in the curved portion 8b of the porous body 8. Further, the slit 81 of the present embodiment is formed in a notch shape that opens on the cylinder bore 2 side (the side opposite to the support 7) but does not open on the support 7 side. Specifically, the slit 81 is formed by making a notch so as not to penetrate the porous body 8, and is formed so that the width becomes narrower from the cylinder bore 2 side toward the support 7 side. As the forming mode including the number of slits 81, various examples as shown in FIGS. 4 (a), (b), (c) and 5 (a), (b) are adopted. An example of this formation mode will be described later.

The porous body 8 is made of a cellulosic sponge in a compressed state, and the cellulosic sponge is maintained in a compressed state, and when it comes into contact with water, this adds an external factor, which triggers the restoration to the state before compression. Has characteristics. More specifically, the cellulosic sponge is a natural material composed of pulp-derived cellulose and natural fibers (for example, cotton) added as reinforcing fibers. Cellulose has a hydrophilic group (OH) and has a property of being chemically compatible with water. Cellulose-based sponge is a porous material, and when it is dried under pressure, the cellulosic molecules are hydrogen-bonded and maintained in a compressed state, while when exposed to water from this state, the water molecules become cellulose. It has the property of dissociating hydrogen bonds between molecules and restoring them from the compressed state. The cellulosic sponge (porous body 8) is integrated with the support 7 by insert-molding the compressed cellulosic sponge together with the support 7. Therefore, the cellulosic sponge is fixed to the support 7 with a part of the resin material constituting the support 7 impregnated in the cellulosic sponge. Since the slit 81 of the porous body 8 has a shape that does not open on the support 7 side, the resin constituting the support 7 is slit when the porous body 8 is insert-molded together with the support 7. Invasion into 81 is suppressed.

The spacer 6 configured as described above is inserted into the cooling water flow path 3 of the internal combustion engine 10 through the opening 30 and arranged. 1, FIG. 2A and FIG. 3A show a state in which the spacer 6 is arranged in the cooling water flow path 3. When the spacer 6 is arranged in the cooling water flow path 3, the porous body 8 is maintained in a compressed state, so that the porous body 8 does not easily interfere with the inner inner wall portion 3c of the cooling water flow path 3 and is smoothly inserted. Will be done. Then, as shown in FIG. 3B, the cylinder head 9 is fastened and integrated on the upper surface of the cylinder block 1 via the head gasket 9a, and then the cooling water w is introduced from the cooling water introduction port 4 into the cooling water flow path 3. be introduced. Further, due to the explosive action of the combustion gas in the combustion chamber 90 of the cylinder head 9, the piston 20 in the cylinder bore 2 repeatedly moves up and down, and the internal combustion engine 10 is put into operation.

As described above, when the cooling water w is introduced into the cooling water flow path 3, the cooling water w comes into contact with the porous body 8 made of a cellulosic sponge, and the porous body 8 is restored to the cylinder bore 2 side (anti-cylinder bore 2 side). Enormous in the compression direction). Along with this restoration, the surface 8a of the porous body 8 comes into contact with the inner inner wall surface 3c of the cooling water flow path 3. Further, when the porous body 8 is restored, a force for expanding the surface of the curved portion 8b on the cylinder bore 2 side in the circumferential direction d of the cooling water flow path 3 (in order to expand the surface of the curved portion 8b in the plane region direction). The power to do) works. At this time, since the slit 81 extending in the depth direction c of the cooling water flow path 3 is formed in the curved portion 8b corresponding to the convex curved portion 71 of the porous body 8, the porous body 8 is restored. The width of the opening of the slit 81 is widened to make up for the lack of elongation of the porous body 8. Therefore, even if the elongation performance of the porous body 8 is low, the influence thereof is alleviated, and the amount of restoration when the curved portion 8b of the porous body 8 is restored from the compressed state to the state before compression is increased. As a result, the curved portion 8b of the porous body 8 comes into contact with the facing inner inner wall surface 3c, the flow of the cooling water w is restricted, and the space between the convex curved portion 71 of the support 7 and the inner inner wall surface 3c is appropriate. Can be cooled to.

4 (a), (b) and (c) and 5 (a) and 5 (b) show various forms of forming the slit 81 formed in the porous body 8.
In the example shown in FIG. 4A, two slits 81, 81 along the depth direction c of the cooling water flow path 3 are located at a portion corresponding to the center of the convex portion 71 of the support 7 in the porous body 8. Is formed. Further, three slits 81 ... Are formed in the vicinity of both sides of the central slit 81 along the depth direction c. That is, a plurality of slits 81 are formed in the center and in the vicinity of both sides thereof, so that a plurality of slits 81 are also formed in the circumferential direction d. The central slit 81 and the slits 81 on both sides thereof are arranged so as to partially overlap each other when viewed in the circumferential direction d of the cooling water flow path 3. In this example, since the length of any of the slits 81 ... Along the depth direction c does not extend to the entire depth direction c of the porous body 8, the porous body 8 is integrated with the support 7. It is possible to reduce the concern that the porous body 8 is torn from the slit 81 at the time of handling such as when handling. Further, the plurality of slits 81 formed in the depth direction c and the circumferential direction d substantially increase the total opening width of the slits 81 ..., and the porous body of the portion corresponding to the convex curved portion 71. 8 can more effectively increase the amount of restoration when restoring from the compressed state to the state before compression. Further, since the slits 81 are not continuous in the entire depth direction c of the porous body 8, the cooling water flow path 3 is located from the first end of the porous body 8 located on the opening 30 side of the cooling water flow path 3. There is no path for cooling water to flow to the second end of the porous body 8 located on the bottom wall portion 31 side of the. Therefore, the porous body 8 can suitably suppress the flow of the cooling water along the depth direction c of the cooling water flow path 3 in the constricted shape portion 3b.

In the example shown in FIG. 4B, one slit 81 along the depth direction c of the cooling water flow path 3 is provided in the center of the curved portion 8b of the porous body 8 in the depth direction c of the porous body 8. It is formed over the entire width of. In this example, since the length of the slit 81 along the depth direction c extends to the entire width of the porous body 8 in the depth direction c, the action of compensating for the insufficient elongation of the porous body 8 due to the slit 81. Is effectively demonstrated. In the example shown in FIG. 4C, only two slits 81 and 81 along the depth direction c of the cooling water flow path 3 are spaced in the depth direction at the center of the curved portion 8b in the porous body 8. Is formed. In this example, it is possible to reduce the concern that the porous body 8 is torn from the slit 81 at the time of handling such as when the porous body 8 is integrated with the support 7.

In the example shown in FIG. 5A, one piece shorter than the total width in the depth direction c of the porous body 8 along the depth direction c of the cooling water flow path 3 is located at the center of the curved portion 8b in the porous body 8. Only the slit 81 is formed. In this example, as compared with the example of FIG. 4A, the concern that the porous body 8 is torn from the slit 81 at the time of handling such as when integrating the porous body 8 with the support 7 is reduced. Can be done. In the example shown in FIG. 5B, four slits 81 are formed in the center of the curved portion 8b of the porous body 8 in a state of being inclined in the same direction d. In this example, the number of slits 81 is smaller than that shown in FIG. 4A, but the porous body 8 starts from the slit 81 when the porous body 8 is handled such as when it is integrated with the support 7. Can reduce the concern that the rupture will occur. Further, the total width of the openings of the slits 81 ... Is substantially increased, and the amount of restoration when the curved portion 8b of the porous body 8 is restored from the compressed state to the state before compression is more effectively increased. Can be planned.
Formation modes other than those shown in FIGS. 4 (a), (b) and (c) and 5 (a) and 5 (b) are also possible, and these various slit 81 formation modes are porous in the convex portion 71. An appropriate forming mode is appropriately adopted according to the resilience of the body 8.

FIG. 6 shows a second embodiment of the spacer according to the present invention. The spacer 6 of the present embodiment is arranged in a part of the cooling water flow path 3, and the spacer main body 7 of the example shows the support 7 of the first embodiment along the arrangement direction of the cylinder bores 2 ... The shape is almost the same as the shape of the right half divided by the center line. Then, the same porous body 8 as described above is integrated on the surface (inner surface) 7a on the cylinder bore 2 side including the convex curved surface 71a of the convex curved portion 71 located between the bores 2 and 2 of the support 7. A slit 81 is formed in the portion of the porous body 8 corresponding to the convex portion 71 in the same forming manner as described above.

The spacer 6 of the present embodiment is integrated with the support 7 in a state where the porous body 8 is maintained in a compressed state, and is inserted into the cooling water flow path 3 through the opening 30 (see FIG. 3) in this state. Is placed. FIG. 6 shows a state in which the spacer 6 is arranged in the cooling water flow path 3. At the time of this insertion, since the porous body 8 is in a compressed state, there is little concern that the porous body 8 becomes a factor of insertion resistance. Then, as in FIG. 3B, the cylinder head 9 is fastened and integrated with the upper surface of the cylinder block 1 to assemble the internal combustion engine 10. After that, when the cooling water is introduced from the cooling water introduction port 4, the cooling water comes into contact with the cellulosic sponge constituting the porous body 8, the cellulosic sponge is restored to the state before compression, and the cooling water flow path 3 It is restored in the width direction and becomes enormous. Due to the restoration of the cellulosic sponge, the surface 8a of the porous body 8 comes into contact with the inner inner wall surface 3c of the cooling water flow path 3. Since the slit 81 is formed in the curved portion 8b of the porous body 8 as in the above example, it is possible to increase the restoration of the curved portion 8b at the time of restoration of the porous body 8. Then, even after this contact, the cellulosic sponge receives a reaction force as the cellulosic sponge is restored, so that the support 7 is displaced so as to be pressed against the outer inner wall surface 3d of the cooling water flow path 3. Further, since the restored cellulosic sponge (porous body 8) is positioned so as to face the flow of the cooling water flowing in the cooling water flow path 3, it functions as a regulating means for regulating the flow of the cooling water. The performance of water flow control of the spacer 6 can be improved.
Since the other configurations are the same as those in the first embodiment, the same reference numerals are given to the common parts, and the description thereof will be omitted.

FIG. 7 shows a third embodiment of the spacer according to the present invention. In the present embodiment, the support 7 has a convex portion 72 protruding to the opposite side of the cylinder bore 2, and the porous body 8 made of a cellulosic sponge includes the convex curved surface 72a of the convex portion 72. It is integrated with the surface (outer surface) 7b on the opposite side to the above. In the illustrated example, the groove width of a part of the arcuate shape portion 3a in the cooling water flow path 3 is widened to the side opposite to the cylinder bore 2, and the outer inner wall surface 3d is bent at two points on the side opposite to the cylinder bore 2. It is formed in a curved shape including a portion. The support 7 has a shape that is curved to the opposite side of the cylinder bore 2 so as to substantially follow the outer inner wall surface 3d at this widened portion. Therefore, the convex curved portion 72 is formed at two positions so as to correspond to the bent shape portion of the outer inner wall surface 3d. A slit 81 similar to the above is formed in the curved portion 8b corresponding to each of the convex portions 72, 72 of the support 7 in the porous body 8. The slit 81 is formed in a notch shape that opens on the side opposite to the support 7 (outer inner wall surface 3d side) but does not open on the support 7 side. Further, in the present embodiment, the slit 81 is opened on the side opposite to the cylinder bore 2 side (the side opposite to the support 2).

The spacer 6 of the present embodiment is also inserted into the cooling water flow path 3 through the opening 30 (see FIG. 3) and arranged. Then, the cylinder head 9 (see FIG. 3B) is fastened and integrated on the upper surface of the cylinder block 1 to assemble the internal combustion engine 10. After that, when the cooling water is introduced into the cooling water flow path 3 from the cooling water introduction port 4, the cooling water comes into contact with the cellulosic sponge constituting the porous body 8, and the cellulosic sponge is restored to the state before compression. It is restored in the width direction of the cooling water flow path 3 and becomes enormous. Due to the restoration of the cellulosic sponge, the surface 8a of the porous body 8 comes into contact with the outer inner wall surface 3d of the cooling water flow path 3. The enlarged view in FIG. 7 shows a state in which the porous body 8 is enormous and even the portion corresponding to the convex portion 72 is in contact with the outer inner wall surface 3d of the facing cooling water flow path 3. Such an enormous state of the porous body 8 also occurs in the other convex portion 72 as well. Since the slit 81 is formed in the curved portion 8b corresponding to the convex curved surface 72 of the porous body 8 as in the above example, the convex portion at the time of restoration of the porous body 8 is formed as in the above example. It is possible to increase the restoration amount of the portion corresponding to 72.
Since the other configurations are the same as those in the above example, the same reference numerals are given to the common parts and the description thereof will be omitted.

In addition, various types of cellulosic sponges can be mentioned, but the sponge is not particularly limited. For example, any of a fine particle product having a very small bubble size, a small particle product having a small bubble size, and a medium grain product having a medium bubble size may be used. Specifically, a cellulosic sponge having a bubble size (diameter) of about 0.1 to 5 mm may be used. The size of these bubbles is determined by the particle size of the crystalline glass used in the process of producing the cellulosic sponge. The cellulosic sponge is preferably composed of cellulose and reinforcing fibers, but is not limited to this, and may be composed of cellulose alone. The cellulosic sponge is not only a sponge made of cellulose itself, but also a cellulosic derivative in which the hydroxyl group of cellulose is left to the extent that it can maintain a compressed state, for example, a sponge made of cellulose ethers, cellulose esters, etc. It may be selected from any of the sponges composed of these mixtures.
In addition to the cellulosic sponge, the material constituting the porous body 8 is a water-swellable sponge, a water-soluble binder, or a foam maintained in a compressed state by a binder that dissolves at a temperature equal to or higher than a predetermined temperature. It may be made of a non-foaming porous body.
Further, the integration of the porous body 8 with the support 7 is not limited to insert molding, and may be performed by mechanical fixing with an adhesive or an appropriate jig.

Further, the slit 81 is not limited to a shape that opens on the opposite side of the support 7 in the compressed state of the porous body 8, and the slit 81 is porous even if it is not opened in the compressed state of the porous body 8. It suffices if the structure 8 can be opened when it becomes enormous. The size of the slit 81 may be appropriately changed. For example, instead of making a cut in the porous body 8, the slit 81 may be formed by removing a part of the porous body 8. Further, although the example in which the slit 81 formed in the porous body 8 does not open on the support 7 side is described, a slit 81 that also opens on the support 7 side can be adopted. In particular, when the support 7 and the porous body 8 are integrated by a method other than insert molding (for example, when they are integrated by adhesion or when the support 7 is made of a material other than synthetic resin), the slit 81 Since there is no concern that the resin will infiltrate inside, there is no problem even if there is an opening on the support 7 side. The formation position of the slit 81 is not limited to the center of the curved portion 8b of the porous body 8, and may be formed on the proximal end side of the curved portion 8b. Further, although the example in which the spacer body 7 is made of a molded body of synthetic resin has been described, it may be made of another material as long as it is more rigid than the material constituting the porous body 8 such as metal. .. Further, the position where the porous body 8 is fixed to the spacer body 7 (the position in the circumferential direction d, the position in the depth direction c of the cooling water flow path 3) and the number of the porous bodies 8 (the number in the circumferential direction d, the cooling water flow path). The number of the depth direction c of 3) is appropriately changed according to the required specifications such as the stability of the spacer 6 in the cooling water flow path 3 or the cooling function of the cooling water w flowing in the cooling water flow path 3. You may. Further, a plurality of spacers of the present invention may be arranged in the cooling water flow path 3, and the number of spacers to be arranged may be appropriately changed according to the space in the cooling water flow path 3, the required specifications, and the like. Furthermore, although a 3-cylinder internal combustion engine has been exemplified as an internal combustion engine to which the spacer of the present invention is applied, the present invention is not limited to this, and can be applied to an engine having another number of cylinders.

10 Internal combustion engine 1 Cylinder block 2 Cylinder bore 3 Cooling water flow path 6 Spacer 7 Support 7a, 7b Side surface of support 71, 72 Convex part 71a, 72a Convex curved surface 8 Porous body 81 Slit c Depth direction d Circumferential direction w Cooling water

Claims (6)

A spacer arranged in a cooling water flow path formed in a cylinder block of an internal combustion engine so as to surround a cylinder bore.
A support made of a rigid material having a convex portion, and
A porous body attached to a side surface of the support including a convex curved surface of the convex portion,
The porous body has a property of being maintained in a compressed state and being restored to a state before compression when a predetermined external factor is added.
A spacer characterized in that a slit that opens on the side opposite to the support is formed in a portion of the porous body corresponding to the convex portion. In the spacer according to claim 1,
The slit is formed so as to extend in the depth direction of the cooling water flow path, and the length of the slit along the depth direction of the cooling water flow path is the depth direction of the cooling water flow path of the porous body. A spacer characterized in that it is formed so as to be shorter than the length along the line. In the spacer according to claim 2.
The spacer is characterized in that a plurality of the slits are formed in the depth direction of the cooling water flow path and the circumferential direction of the cooling water flow path. In the spacer according to any one of claims 1 to 3.
A spacer characterized in that the support is made of a hard synthetic resin, is integrally molded together with the porous body, and the slit has a shape that does not open on the support side. In the spacer according to any one of claims 1 to 4.
The spacer is characterized in that the porous body is made of a cellulosic sponge in a compressed state, and the addition of the external factor is contact of water with the cellulosic sponge. In the spacer according to any one of claims 1 to 5.
A spacer characterized in that a plurality of the cylinder bores are arranged, and the convex portion has a shape protruding toward a portion between adjacent silin bores.

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