JP7445951B2 - 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 (flow rate, flow velocity, etc.) of the circulating cooling water is inserted into the cooling water flow path of the internal combustion engine through an opening (see, for example, Patent Document 1). In the spacer disclosed in Patent Document 1, a member is provided on the side surface of the spacer main body (support body) made of synthetic resin or the like on the cylinder bore side, which expands when it comes into contact with cooling water and contacts the wall surface of the cylinder bore side of the cooling water flow path. is installed. The members attached to the spacer body in this way are low in bulk (thin) before becoming bulky, so when inserting the spacer into the cooling water flow path, the insertion resistance is reduced to ensure smooth insertion. After being placed in the cooling water flow path, it becomes huge and regulates the flow of cooling water.

Japanese Patent Application Publication No. 2016-128256

Incidentally, Patent Document 1 describes an example of a method of manufacturing the above-described spacer by insert molding (see FIG. 14 of the same patent document and its related description). In this example, when placing the foam in the lower mold, positioning was done by inserting a positioning protrusion provided at a predetermined position on the lower mold into a through hole (through hole) provided in advance in the foam. After that, the upper mold is clamped. In this mold-clamped state, the tips of the protrusions enter the holes provided at opposing positions in the upper mold. Therefore, in a spacer obtained by injecting resin and insert molding in this state, a through hole is formed that passes through the foam and the support and communicates between the front and back (between the inner and outer surfaces) of the spacer. In this way, when a spacer having a through hole that communicates between the front and back sides is placed in the cooling water flow path and cooling water is allowed to flow, the cooling water will flow between the front and back sides of the spacer through the through hole. The regulatory function of

The present invention has been made in view of the above-mentioned circumstances, and provides a spacer that can suppress the flow of cooling water between the front and back surfaces of the spacer through the through-holes even if the porous body is provided with through-holes. is intended to provide.

The spacer according to the present invention is a spacer that is arranged in a cooling water flow path provided in a cylinder block of an internal combustion engine so as to surround a cylinder bore, and includes a support made of synthetic resin and an inner or outer surface of the support. , a porous body attached by integral molding, the porous body is provided with a through hole penetrating in the thickness direction thereof, and the support body is formed so as to close the opening of the through hole. The support body is provided with a protrusion that protrudes on the opposite side of the porous body at a location corresponding to the through hole, and the protrusion communicates with the through hole and is connected to the porous body. The supporting body is formed in a bottomed cylindrical shape with a closed opening on the opposite side to the mass body, and when the support body disposed in the cooling water flow path is displaced toward the inner wall surface side of the cooling water flow path, the tip of the support body is closed. It is characterized by being in contact with the inner wall surface .

According to the spacer of the present invention, since the opening of the through hole provided in the porous body is closed by the support body, when the spacer is placed in the cooling water flow path, through the through hole, It is possible to suppress the flow of cooling water between the front and back surfaces of the spacer. Therefore, the amount of cooling water directed toward the cylinder bore side can be maintained at a predetermined amount, and it is possible to prevent the expected regulation function of the spacer from deteriorating. In addition, since the protrusion is provided at the location corresponding to the through hole, even if the thickness of the support is thin, the support can be molded to reliably close the opening of the through hole. It is possible to accurately prevent cooling water from flowing between the front and back surfaces of the spacer. Even if the protrusion is cylindrical, since this cylindrical shape has a bottom, the opening of the through hole is substantially closed, and the above effect can be achieved in the same way.

In the spacer according to the present invention, a plurality of the through holes may be provided, and the protrusion may be provided at a location corresponding to each of the through holes.
According to this, even if there are multiple through-holes, each of them is provided with a protrusion, so even if the thickness of the support is thin or uneven, the opening of each through-hole can be adjusted by the support. The spacer is reliably maintained in a closed state, and cooling water can be accurately prevented from flowing between the front and back sides of the spacer through the through hole.

In the spacer according to the present invention, the porous body may have a property of expanding in the thickness direction from a compressed state when a predetermined external factor is applied.
According to this, since the porous body can be placed in the cooling water flow path in a compressed state, it can be smoothly placed without interfering with the side walls of the cooling water flow path.

In the spacer according to the present invention, the through hole may be a hole through which a positioning protrusion for positioning the porous body in a mold is inserted when insert molding the porous body and the support body.
According to this, even though the through-hole in the porous body is formed for positioning during insert molding, the opening of this through-hole is blocked by the support, so the spacer can be inserted between the front and back sides through this through-hole. It is possible to suppress the flow of cooling water.

According to the spacer according to the present invention, even if a porous body is provided with a through hole, it is possible to suppress the flow of cooling water between the front and back surfaces of the spacer through the through hole.

1 is a schematic cross-sectional plan view showing an example of a state in which a spacer according to the present invention is arranged in a cooling water flow path of an internal combustion engine. The first embodiment of the spacer according to the present invention is shown, in which (a) is an enlarged view of the X part in FIG. It is a figure similar to (a) showing the state in which the mass body has expanded. (a) is a sectional view taken along the YY line in FIG. 2(a), and (b) is a sectional view taken along the ZZ line in FIG. 2(b). It is a cross-sectional view showing a second embodiment of a spacer according to the present invention. It is a figure similar to FIG. 4 showing a modification of the second embodiment. It is a figure similar to FIG. 4 which shows the third embodiment of the spacer based on this invention. (a), (b), and (c) are process diagrams schematically showing a method for manufacturing a spacer according to a second embodiment, and (a) shows a step of placing a compressed porous body in a mold. , (b) shows the step of integrally insert-molding the same porous body and resin, and (c) shows the spacer obtained by demolding. A fourth embodiment of the spacer according to the present invention is shown, (a) and (b) are perspective views schematically showing the spacer, and (c) is a sectional view taken along the line WW in FIG. 8(b). It is. (a) and (b) are process diagrams schematically showing a method for manufacturing a spacer according to a fourth embodiment, and (a) is a perspective view showing a process of placing a compressed porous body in a mold. , (b) shows a step of integrally insert-molding the same porous body and resin. 5A and 5B are perspective views schematically showing a fifth embodiment of a spacer according to the present invention; FIGS. (a) and (b) are process diagrams schematically showing a method for manufacturing a spacer according to a fifth embodiment, and (a) is a perspective view showing a process of placing a compressed porous body in a mold. , (b) shows a step of integrally insert-molding the same porous body and resin. (a) and (b) are process diagrams schematically showing a method for manufacturing a spacer according to a sixth embodiment, and (a) and (b) show steps up to placing a compressed porous body in a mold. The process is shown below. (a) and (b) are process diagrams schematically showing a method for manufacturing a spacer according to a sixth embodiment, and (a) is a partially enlarged view of the step of integrally insert-molding a porous body and a resin. (b) shows a partially enlarged view of the spacer obtained by demolding. (a) to (d) are partially enlarged views showing various further modifications of the spacer according to the present invention.

Embodiments of the present invention will be described below with reference to FIGS. 1 to 14. 1 to 3 show a first embodiment of a spacer according to the present invention, and FIG. 1 shows a state in which the spacer of the same embodiment is arranged in a cooling water flow path 3 of a cylinder block 1 in an internal combustion engine 10. It shows. A 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 arranged adjacent to each other in series. 1a... are insertion holes for bolts (not shown) for integrally fastening the cylinder head 4 (see FIG. 3(b)) to the cylinder block 1 via the head gasket 4a (see FIG. 3(b)). A series of open deck type groove-shaped cooling water passages 3 are formed around the three cylinder bores 2 so as to surround these cylinder bores 2 . A cooling water inlet 1b and a cooling water outlet 1c communicating with the cooling water passage 3 are provided at appropriate positions in the cylinder block 1. The cooling water outlet 1c is pipe-connected to a radiator (not shown), and the outlet side of the radiator is pipe-connected to the cooling water inlet 1b via a water pump (not shown). Thereby, the cooling water (including antifreeze) is configured to circulate between the cooling water flow path 3 and the radiator. Note that when the cylinder head 4 is also provided with a cooling water passage (not shown), the cooling water passage 3 of the cylinder block 1 and the cooling water passage (not shown) of the cylinder head are configured to communicate with each other. In this case, the cylinder block 1 does not need to have the cooling water outlet, and the cylinder head is provided with a cooling water outlet, to which piping leading to the radiator is connected.

The cooling water flow path 3 includes an arcuate portion 3a formed to surround the cylinder bore 2, and a constricted portion 3b formed in a pair close to each other between adjacent cylinder bores 2. ing. The groove widths of the constricted portions 3b are larger than the groove widths of the other arcuate portions 3a of the cooling water flow path 3. Both inner wall surfaces of the cooling water flow path 3 are formed to correspond to the arcuate portions 3a... and the constricted portions 3b, and an inner wall surface (inner inner wall surface) 3c on the side of the cylinder bore 2 and a side opposite to the cylinder bore 2. The inner wall surface (outer inner wall surface) 3d. A piston 5 that reciprocates along the axial direction is provided in each cylinder bore 2, and the piston 5 slides on the inner circumferential surface 2aa of the cylinder bore wall 2a via a piston ring 5a attached to the outer circumference of the cylinder bore 2. It is configured so that it can be done.

A spacer 6 is arranged within the cooling water flow path 3 . The spacer 6 of this embodiment is attached to a support body 7 made of synthetic resin and an inner surface (face facing the cylinder bore 2 side) 7a of the support body 7 by integral molding, and is a long sheet in the circumferential direction of a circular arc portion 70 to be described later. A porous body 8 having a shape. The support body 7 in this embodiment has a semi-cylindrical shape and is disposed in a half of the cooling water flow path 3 (one side of the center line L along the series direction of the cylinder bores 2). Therefore, this semi-cylindrical support body 7 has a shape in which shaped portions corresponding to the plurality of circular arc shaped portions 3a and constricted shaped portions 3b of the cooling water flow path 3 are connected. Specifically, as shown in FIG. 1, the support body 7 connects a plurality of circular arc parts 70 arranged in the circular arc shaped part 3a of the cooling water flow path 3 and adjacent circular arc parts 70, 70, and The connecting portion 71 is disposed in the constricted portion 3b of the cooling water flow path 3. A porous body 8 is attached to each arcuate portion 70 on the inner surface 7a of the support body 7. The porous body 8 is provided with a through hole 8a that penetrates in the thickness direction thereof, and the support body 7 is formed so as to close the opening 8aa of the through hole 8a. In this embodiment, the support body 7 is provided with a protrusion 7c that protrudes on the opposite side from the porous body 8 at a location corresponding to the through hole 8a. Furthermore, this protrusion 7c is formed in a bottomed cylindrical shape that communicates with the through hole 8a and has an opening 7ca on the opposite side of the porous body 8 closed. In other words, the protrusion 7c is composed of a cylindrical portion 7cb and a bottom portion 7cc that closes the opening 7ca of the cylindrical portion 7cb (see FIGS. 2(a) and 2(b); in FIG. (not shown). Thereby, the opening 8aa of the through hole 8a in the porous body 8 is closed by the protrusion 7c, and is substantially closed by the support body 7. The protrusion height of the protrusion 7c is smaller than the thickness of the support body 7. Further, the protrusion height of the protrusion 7c is smaller than the distance between the outer surface 7b of the support body 7 and the outer inner wall surface 3d of the cooling water flow path 3 when the spacer 6 is disposed closer to the cylinder bore 2. The inner diameter of the cylindrical protrusion 7c is the same as the inner diameter of the through hole 8a. The protrusion 7c is provided at a location corresponding to the top of the circular arc portion 70 on the support body 7.

The porous body 8 of the spacer 6 in this embodiment is made of a compressed cellulose sponge, and when the cellulose sponge is maintained in a compressed state and comes into contact with water, this causes the addition of an external factor, which triggers the addition of an external factor. It has the property of restoring to the state before compression. 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. The cellulose sponge (porous body 8) is integrated into the support 7 by insert molding the compressed cellulose sponge 8 together with the support 7, as will be described later. Therefore, the cellulose sponge 8 is fixed to the inner surface 7a of the support 7, with the cellulose sponge 8 being partially impregnated with the resin material constituting the support 7. The through hole 8a of the cellulose sponge 8 is a hole into which a positioning protrusion for positioning the porous body 8 in the mold is inserted during insert molding.

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 thereof. 1, FIG. 2(a), and FIG. 3(a) show a state in which the spacer 6 is disposed within the cooling water flow path 3. Since the porous body 8 is maintained in a compressed state when placing the spacer 6 in the cooling water flow path 3, the porous body 8 is unlikely to interfere with the inner wall surface 3c of the cooling water flow path 3, and can be inserted smoothly. be done. Next, the cylinder head 4 is fastened and integrated with the upper surface of the cylinder block 1 via the head gasket 4a, and then the cooling water w is introduced into the cooling water passage 3 from the cooling water inlet 1b. Then, due to the explosive action of the combustion gas within the combustion chamber 40 of the cylinder head 4, the piston 5 within the cylinder bore 2 repeatedly moves up and down, and the internal combustion engine 10 enters the operating state.

As mentioned above, when the cooling water is introduced into the cooling water flow path 3, it comes into contact with the porous body 8 made of cellulose sponge, and the porous body 8 is restored and expands toward the cylinder bore 2 side (in the anti-compression direction). become With this restoration, the surface 8b of the porous body 8 (the surface on the cylinder bore 2 side) comes into contact with the inner inner wall surface 3c of the cooling water flow path 3. The porous body 8 further expands even after its surface 8b comes into contact with the inner inner wall surface 3c, and the support body 7 is displaced toward the side opposite to the cylinder bore 2 due to the reaction force. With this displacement, the tip of the protrusion 7c comes into contact with the outer inner wall surface 3d of the cooling water flow path 3. FIG. 2(b) and FIG. 3(b) show a state in which the porous body 8 contacts the cooling water w and expands. The porous body 8 is provided at a location where the cooling capacity of the cooling water w flowing through the cooling water flow path 3 is excessive with respect to the cylinder bore wall 2a, and when the porous body 8 becomes enlarged, the porous body 8 is Dam up the flow of water. Then, the porous body 8 reduces the cooling ability of the cooling water w to the cylinder bore wall 2a, exhibits a supercooling suppressing function, and appropriately adjusts the cooling state to the cylinder bore wall 2a.

In the spacer 6 of this embodiment, the porous body 8 is provided with a through hole 8a that penetrates from the front and back sides, but since the opening 8aa of the through hole 8a is blocked by the support 7, cooling water can be It is possible to prevent w from flowing between the front and back sides of the spacer 6 through this through hole 8a. In other words, with the spacer 6 as a reference, the cooling water flowing on the opposite cylinder bore 2 side of the cooling water passage 3 is suppressed from flowing into the cylinder bore 2 side of the cooling water passage 3 through the through hole 8a provided in the porous body 8. can. Therefore, the amount of cooling water w directed toward the cylinder bore 2 can be maintained at a predetermined amount, and the expected function of the spacer 6 can be prevented from deteriorating. Further, since the support 7 is provided with the protrusion 7c at a location corresponding to the through hole 8a, even if the support 7 is thin, the opening 8aa of the through hole 8a can be reliably closed by the support 7. maintained in a clean state. Furthermore, since the protrusion 7c communicates with the through hole 8a and is formed into a bottomed cylindrical shape with its opening 7ca closed, the opening 8aa of the through hole 8a is substantially closed by the support 7. Therefore, the same effect as described above can be achieved. Furthermore, as the porous body 8 expands, the protrusion 7c comes into contact with the outer inner wall surface 3d of the cooling water flow path 3, so that the outer surface 7b of the support body 7 and the outer inner wall surface 3d of the cooling water flow path 3 are A gap is ensured in between. Therefore, by circulating the cooling water w in this gap portion, it is possible to suppress the flow of the cooling water w from being stagnant within the cooling water flow path 3.

FIG. 4 shows a second embodiment of the spacer according to the invention. The spacer 6 of this embodiment is a partial spacer in which the support body 7 consists only of a shaped part corresponding to the circular arc shaped part 3a of the cooling water flow path 3 in FIG. They are placed individually in appropriate locations. In the spacer 6 of this embodiment as well, a porous body 8 similar to that described above is integrally attached to the inner surface 7a of the arc-shaped support 7. However, in the illustrated example, a stepped recess 7aa having the same external shape as the porous body 8 is formed on the inner surface 7a of the support 7, and the porous body 8 is attached so as to fit into this recess 7aa. ing. In this way, the porous body 8 is attached so as to fit into the recess 7aa of the support body 7, so that the attached state of the porous body 8 is stabilized. A bottomed cylindrical protrusion 7c similar to that described above is provided at a location corresponding to the through hole 8a of the porous body 8 in the support body 7, and an opening 8aa of the through hole 8a on the opposite side of the porous body 8 is provided. It is substantially closed by the support 7.

The spacer 6 of this embodiment is also arranged within the cooling water flow path 3 of the cylinder block 1 shown in FIG. When the cooling water is introduced into the cooling water passage 3, the porous body 8 comes into contact with the cooling water and expands toward the cylinder bore 2, and the surface 8b of the porous body 8 touches the inner wall surface 3c of the cooling water passage 3. come into contact with At this time, the support body 7 is displaced toward the side opposite to the cylinder bore 2 in the same manner as described above, and the protrusion 7c comes into contact with the outer inner wall surface 3d of the cooling water flow path 3. Since the opening 8aa of the through hole 8a is substantially closed by the support 7, the same effect as described above can be obtained.
Since other functions and effects are the same as those of the first embodiment, the same reference numerals are given to the common parts (some of them are omitted from the drawings), and the explanation thereof will be omitted here.

FIG. 5 shows a modification of the second embodiment of the spacer according to the invention. In this example, the porous body 8 is provided with a plurality of through holes 8a that penetrate from the front and the back, and cylindrical protrusions 7c similar to those described above are provided at locations corresponding to each of the through holes 8a. ing. In the illustrated example, the through holes 8a and the protrusions 7c are arranged parallel to each other at equal intervals in the circumferential direction of the cooling water flow path 3. Further, the protrusion heights of the plurality of protrusions 7c are the same. Furthermore, the tips of each of the protrusions 7c are formed to form concentric curved surfaces. The protrusion 7c is formed into a bottomed cylindrical shape with its opening 7ca closed, so that the opening 8aa of each through hole 8a in the porous body 8 is substantially closed by the support 7. ing.

In this way, when the porous body 8 is provided with a plurality of through holes 8a..., the porous body 8 can be more stably positioned at a predetermined position of the mold during insert molding of the spacer 6, which will be described later. can do. Further, since the plurality of protrusions 7c are provided on the support body 7 so as to correspond to the respective through holes 8a, the protrusions 7c have the same protrusion height, and the tip portions form concentric curved surfaces. When the porous body 8 expands inside, the plurality of protrusions 7c come into contact with the outer inner wall surface 3d of the cooling water flow path 3. Therefore, in combination with the porous body 8 coming into contact with the inner inner wall surface 3c of the cooling water flow path 3, the spacer 6 is stably held at a predetermined position within the cooling water flow path 3. In particular, in the case of the illustrated spacer 6, being stably held at a predetermined position within the cooling water flow path 3 is effective in suppressing the expected deterioration of the function of the spacer 6.
Other functions, effects, etc. are the same as those in the first and second embodiments, so common parts are denoted by the same reference numerals (some illustrations are omitted), and their explanations are omitted here as well.

FIG. 6 shows a third embodiment of a spacer according to the invention. Although the spacer 6 of this embodiment is also a partial spacer, the support body 7 does not have the protrusion 7c provided at the location corresponding to the through hole 8a of the porous body 8 as in the previous embodiment. However, the opening 8aa of the through hole 8a is closed by the support 7. The support body 7 has a recess 7d that is recessed in the thickness direction from the porous body 8 side at a location corresponding to the through hole 8a. The recessed portion 7d is a portion where a protrusion for positioning the porous body 8 in a mold protrudes from the porous body 8 in a manufacturing method to be described later. The spacer 6 of this embodiment is also disposed within the arc-shaped portion 3a of the cooling water flow path 3, similarly to the second embodiment. When the cooling water is introduced into the cooling water passage 3, the porous body 8 expands, and the surface 8b of the porous body 8 comes into contact with the inner wall surface 3c of the cooling water passage 3. Since the outer surface 7b of the support 7 does not have the protrusion 7c as described above, the outer surface 7b of the support 7 directly contacts the outer inner wall surface 3d of the cooling water flow path 3. This makes it easier for the flow of the cooling water w to stagnate in the cooling water flow path 3 compared to the first and second embodiments, but depending on the engine specifications, it may be more suitable for suppressing overcooling of the cylinder bore wall 2a. There is also.
Other functions, effects, etc. are the same as those of the first and second embodiments, so their explanations will be omitted here as well.

FIGS. 7A, 7B, and 7C show an example of a method for manufacturing a spacer according to the present invention, taking the method for manufacturing the spacer 6 of the second embodiment as an example. Such a spacer 6 is manufactured using a molding apparatus (molding mold) 100 as shown in FIGS. 7(a) and 7(b). A lower mold 101 and an upper mold 103 constituting the molding apparatus 100 are configured to form an arc-shaped cavity 102 corresponding to the arc-shaped portion 3a of the cooling water flow path 3 when the molds are clamped. The cavity 102 is sized to surround the four circumferences of the support 7 constituting the spacer 6, and is composed of a lower mold cavity 102a made of a convex curved surface of the lower mold 101, and an upper mold cavity 102b made of a concave curved surface of the upper mold 103. be done. A cylindrical projection 102aa that can be inserted into the through hole 8a of the porous body 8 is formed approximately at the center of the lower mold cavity 102a (top of the convex curved surface). Further, a cylindrical bottomed hole portion 102ba that can receive the tip of the projection 102aa is formed approximately at the center of the upper mold cavity 102b (the bottom of the concave curved surface). The diameter of this bottomed hole portion 102ba is larger than the diameter of the projection 102aa. In addition, the depth of the bottomed hole 102ba is such that when the lower mold 101 and the upper mold 103 are clamped, a predetermined gap is ensured between the bottom of the bottomed hole 102ba and the tip surface of the protrusion 102aa. It is said to be the size to be used. Furthermore, a gate portion 103a for injecting resin into the cavity 102 is formed in the upper mold 103.

When manufacturing the spacer 6 shown in FIG. 7(c) using the molding apparatus 100, first, the spacer 6 is cut into a predetermined size and a through hole 8a is formed at a predetermined position on the lower mold cavity 102a. A rectangular porous body 8 is arranged. Next, the porous body 8 is positioned by fitting the through hole 8a of the porous body 8 into the protrusion 102aa of the lower mold cavity 102a, and then the upper mold 103 is clamped to the lower mold 101. The protrusion 102aa is configured such that its tip can be inserted into the bottomed hole 102ba of the upper mold cavity 102b when the upper mold 103 is clamped. When the upper mold 103 is clamped, the upper mold cavity 102b acts on the left and right sides of the porous body 8 positioned above the lower mold cavity 102a, deforming the porous body 8 into an arc shape. In this state, molten resin r is injected into the cavity 102 from the gate portion 103a to perform insert molding. When the resin r is injected from the gate portion 103a, the surface 8b of the porous body 8 is further deformed into an arcuate shape by the injection pressure of the resin r so as to follow the lower mold cavity 102a having a convex curved surface. In this state, the insert molding is performed.

In this insert molding, the porous body 8 is positioned by the fitting between the through hole 8a and the protrusion 102aa, so there is no concern that the porous body 8 will be misaligned due to the flow pressure of the resin r in the cavity 102. The injected resin r is integrated into the back surface 8c of the porous body 8 and its four circumferential end surfaces. During this insert molding, if an adhesive is applied to the back surface 8c and the four circumferential end surfaces of the porous body 8 to modify the surface condition, the resin r can be firmly integrally molded to the porous body 8.

When the molding is completed and the mold is removed, the porous body 8 is securely integrated with the support body 7 at a predetermined position (fitted into the recess 7aa), as shown in FIG. 7(c). A spacer 6 is obtained. A cylindrical protrusion 7c communicating with the through-hole 8a is formed at a location in the support body 7 corresponding to the through-hole 8a of the porous body 8 due to the above-mentioned size relationship between the diameters of the bottomed hole 102ba and the protrusion 102aa. is formed. Furthermore, due to the size relationship between the depth of the bottomed hole 102ba and the height of the projection 102aa, the cylindrical projection 7c is formed with a bottom, thereby substantially blocking the opening 8aa of the through hole 8a. It is said that the state of The obtained spacer 6 is placed at a suitable position in the arc-shaped portion 3a of the cooling water passage 3 provided in the cylinder block 1 as shown in FIGS. 1 to 3, and exhibits the above-mentioned functions and effects.

Note that although FIG. 7 shows a method for manufacturing the spacer of the second embodiment, the spacer 6 of the first embodiment, the modification of the second embodiment, and the third embodiment are also manufactured in different ways. The same can be produced by using a correspondingly configured molding device 100. In particular, when the support body 7 does not have the protrusion 7c as in the third embodiment, the protrusion 102aa penetrates the through hole 8a of the porous body 8 but does not reach the concave curved surface of the upper mold cavity 102b. considered to be high. Therefore, the concave curved surface of the upper mold cavity 102b does not have a bottomed hole portion 102ba as shown in FIG. 7(a). However, if the gap between the tip surface of the protrusion 102aa and the concave curved surface of the upper mold cavity 102b is small, the above-described bottomed hole 102ba may be provided in the concave curved surface of the upper mold cavity 102b. As a result, a solid protrusion can be formed at a location corresponding to the opening 8aa of the through hole 8a, and even if it is necessary to provide the protrusion 102aa during manufacturing, the thickness of the location corresponding to the protrusion 102aa is thinner and the strength is increased. can suppress the decline in

8 and 9 show a fourth embodiment of a spacer according to the present invention. The spacer 6 of this embodiment is also a partial spacer in which a porous body 8 similar to that described above is integrally attached to the inner surface 7a of an arc-shaped support 7. Further, similarly to the example shown in FIG. 4 and the like, a recess 7aa having the same external shape as the porous body 8 is formed in the inner surface 7a of the support body 7 in a stepped shape. However, the spacer 6 of this embodiment differs from the above-described embodiments in that the support body 7 is provided with a groove 7e formed adjacent to the outer edge of the porous body 8. Specifically, the groove portion 7e in the illustrated example is formed in the shape of a concave groove along each of the upper and lower edges of the horizontally long rectangular porous body 8. According to this, a gap is formed between the outer edge of the porous body 8 and the support body 7 as shown in FIG. The body 8 can easily expand as desired. The spacer 6 is also different in that horizontally elongated strip-shaped protrusions 7f are provided on the outer surface 7b of the support body 7 above and below with the protrusions 7c interposed therebetween. A pair of protrusions 7f are formed substantially in parallel and are formed as ribs for maintaining the arcuate shape of the spacer 6. The protrusion 7f may be formed to protrude less than the protrusion 7c as shown in FIG. 8(c), or may be formed to protrude more than the protrusion 7c even if the protrusion is approximately the same amount. It's okay. By adjusting the amount of protrusion of the protruding portion 7f in this manner, as the porous body 8 expands, the protruding portion 7f will come into contact with the outer inner wall surface when installed in the cooling water flow path, similar to the protruding portion 7c. Therefore, a gap can be secured between the outer surface 7b of the support body 7 and the outer inner wall surface of the cooling water flow path.
Since other functions and effects are the same as those of the other embodiments, the same reference numerals are given to the common parts (some of them are omitted from the drawings), and the explanation thereof will be omitted here.

Next, an example of a method for manufacturing the spacer 6 according to the fourth embodiment will be described with reference to FIG. 9. Regarding the manufacturing method, parts common to those in the example described with reference to FIG. 7 are denoted by the same reference numerals (some illustrations are omitted), and the description thereof will be omitted here. The spacer 6 according to the fourth embodiment is manufactured using a molding apparatus (molding mold) 100 as shown in FIGS. 9(a) and 9(b). A lower mold 101 and an upper mold 103 constituting the molding apparatus 100 are configured to form an arc-shaped cavity 102 corresponding to the arc-shaped portion 3a of the cooling water flow path 3 when the molds are clamped. A cylindrical projection 102aa that can be inserted into the through hole 8a of the porous body 8 is formed approximately at the center of the lower mold cavity 102a formed of the convex curved surface of the lower mold 101 (the top of the convex curved surface). A plurality of protrusions 101a are formed above and below with an interval 102aa in between. This protruding strip 101a is formed in a band shape, and when the porous body 8 is placed on the lower mold 101 as shown in FIG. In addition, the groove portion 7e formed on the inner surface 7a of the support body 7 described above is formed. In addition, a cylindrical bottomed hole 102ba that can receive the tip of the protrusion 102aa is formed approximately at the center of the upper mold cavity 102b (the bottom of the concave curved surface), and the above-mentioned protrusion 7f A second bottomed hole portion 103b is formed.

When manufacturing the spacer 6 shown in FIG. 8(c) using the molding apparatus 100, first, the spacer 6 is cut into a predetermined size and a through hole 8a is formed at a predetermined position on the lower mold cavity 102a. A rectangular porous body 8 is arranged. Next, the porous body 8 is positioned by fitting the through hole 8a of the porous body 8 into the protrusion 102aa of the lower mold cavity 102a, and then the upper mold 103 is clamped to the lower mold 101. The protrusion 102aa is configured such that its tip can be inserted into the bottomed hole 102ba of the upper mold cavity 102b when the upper mold 103 is clamped. When the upper mold 103 is clamped, the upper mold cavity 102b acts on the left and right sides of the porous body 8 positioned above the lower mold cavity 102a, deforming the porous body 8 into an arc shape. Further, at this time, since the convex strips 101a of the lower mold 101 hold the upper and lower outer edges of the porous body 8, displacement of the porous body 8 can be suppressed. In this state, molten resin r is injected into the cavity 102 from the gate portion 103a to perform insert molding.

In this insert molding, the porous body 8 has no fear of positional shift due to the flow pressure of the resin r in the cavity 102 due to the fitting between the through hole 8a and the protrusion 102aa and the regulation by the protruding strip 101a. . The injected resin r is fixed to the back surface 8c of the porous body 8 and the four peripheral end surfaces of the porous body 8. When the molding is completed and the mold is removed, the porous body 8 is securely integrated with the support body 7 at a predetermined position (fitted into the recess 7aa), as shown in FIG. 8(c). , a spacer 6 with high relative positional accuracy between the support body 7 and the porous body 8 can be obtained. The obtained spacer 6 is placed at an appropriate position in the arc-shaped portion 3a of the cooling water passage 3 provided in the cylinder block 1 as shown in FIGS. 1 to 3, and produces the above-mentioned functions and effects.

10 and 11 show a fifth embodiment of a spacer according to the present invention. The spacer 6 of this embodiment is also a partial spacer in which a porous body 8 similar to that described above is integrally attached to the inner surface 7a of an arc-shaped support 7. Further, similarly to the example shown in FIG. 4 and the like, a recess 7aa having the same external shape as the porous body 8 is formed in the inner surface 7a of the support body 7 in a stepped shape. However, the spacer 6 of this embodiment has a first through hole 80a provided in the center of the porous body 8 in the circumferential direction of the arcuate portion 70, and second through holes provided on both sides with the first through hole 80a in between. This embodiment differs from the first, third, and fourth embodiments described above in that it includes a hole 80b. Specifically, the illustrated porous body 8 has a perfectly circular first through hole 80a formed in its center, and oblong second through holes on both sides of the first through hole 80a. Holes 80b, 80b are formed. The second through hole 80b is formed in a long hole shape that is elongated in the circumferential direction of the arc portion 70. According to this, similarly to the spacer 6 shown as a modified example of the second embodiment shown in FIG. It can be positioned and placed. Further, as shown in FIG. 10(b), on the outer surface 7b of the support body 7, a plurality of protrusions 7c have the same protrusion height so as to correspond to each of the through holes 8a, and the tip portions form concentric curved surfaces. It is set up like this. Therefore, when the porous body 8 expands, the plurality of protrusions 7c come into contact with the outer inner wall surface of the cooling water flow path, and this, coupled with the fact that the porous body 8 contacts the inner inner wall surface of the cooling water flow path, causes the The spacer 6 of the fifth embodiment is stably held at a predetermined position within the cooling water flow path.
Other functions, effects, etc. are similar to those of the other embodiments, so common parts are denoted by the same reference numerals (some illustrations are omitted), and description thereof will be omitted here.

Next, an example of a method for manufacturing the spacer 6 according to the fifth embodiment will be described with reference to FIG. 11 and the like. Regarding the manufacturing method, the same reference numerals are given to the parts common to the examples described so far (some illustrations are omitted), and the explanation thereof will be omitted here. The spacer 6 according to the fifth embodiment is manufactured using a molding apparatus (molding mold) 100 as shown in FIGS. 11(a) and 11(b). A lower mold 101 and an upper mold 103 constituting the molding apparatus 100 are configured to form an arc-shaped cavity 102 corresponding to the arc-shaped portion 3a of the cooling water flow path 3 when the molds are clamped. A cylindrical projection 102aa that can be inserted into the first through hole 80a of the porous body 8 is formed approximately at the center of the lower mold cavity 102a formed of the convex curved surface of the lower mold 101 (top of the convex curved surface). Positioning protrusions 104 are provided on both sides of the protrusion 102aa with an interval between them. The positioning protrusions 104 have a cylindrical shape and are configured to move up and down as a pair with the protrusion 102aa in between, and their tip portions 104a are formed into obliquely inclined surfaces. If these protrusions 102aa and positioning protrusions 104, 104 are inserted into the first through hole 80a and second through holes 80b, 80b formed in the porous body 8, the porous body 8 can be positioned at a desired position on the lower mold 101. It is possible to hold the porous body 8 so that it does not shift due to the flow pressure of the resin r during molding. Further, a cylindrical bottomed hole portion 102ba that can receive the tip of the projection 102aa is formed approximately at the center of the upper mold cavity 102b (the bottom of the concave curved surface). Further, the upper mold cavity 102b is formed with a cylindrical second bottomed hole portion 103b that can receive the tip portions 104a of the above-mentioned positioning projections 104, 104. The second bottomed hole portion 103b is formed approximately parallel to the inclined surface of the tip portion 104a of the positioning projection 104 and in accordance with the diameter of the positioning projection 104. A plurality of protrusions 7c are formed on the outer surface 7b of the support body 7 by the bottomed hole portion 102ba and the second bottomed hole portion 103b. The protruding dimensions of the protrusions 7c are determined based on the assumption that when the porous body 8 is installed in the cooling water flow path and expands, the plurality of protrusions 7c will come into contact with the outer inner wall surface of the cooling water flow path. It is set up so that it can be controlled.

When manufacturing the spacer 6 shown in the fifth embodiment using the molding apparatus 100, first, the first through hole 80a and the first through hole 80a are cut into a predetermined size in advance on the lower mold cavity 102a, and the first through hole 80a and the first through hole 80a are formed in a predetermined position. A rectangular porous body 8 in which two through holes 80b, 80b are formed is arranged. Next, after positioning the porous body 8 by fitting the first through hole 80a of the porous body 8 into the protrusion 102aa of the lower mold cavity 102a, the positioning protrusion 104 is made to protrude (see FIG. 11(a)), and the porous body 8 is positioned. After inserting the positioning protrusion 104 into the second through hole 80b of the body 8, the upper mold 103 is clamped to the lower mold 101 (see FIG. 11(b)). The protrusion 102aa and the positioning protrusions 104, 104 are configured such that their tips can be inserted into the bottomed hole 102ba and the second bottomed hole 103b of the upper mold cavity 102b when the upper mold 103 is clamped. has been done. When the upper mold 103 is clamped, the left and right sides of the porous body 8 placed on the lower mold cavity 102a are pressed by the upper mold 103 and bent into an arc shape inside the molding apparatus 100. It can be transformed with. At this time, the positional shift of the porous body 8 can be suppressed by the projections 102aa and the positioning projections 104, 104. Furthermore, as the porous material 8 is bent along the arc shape of the lower mold 101, the relative position between the second through hole 80b and the positioning protrusion 104 is displaced, but the second through hole 80b is elongated. Therefore, displacement of the position relative to the positioning protrusion 104 is allowed, and interference of the positioning protrusion 104 with the porous body 8 can be suppressed. In this state, molten resin r is injected into the cavity 102 from the gate portion 103a to perform insert molding.

In this insert molding, as described above, since the position is determined by the fitting between the first through hole 80a and the projection 102aa and the fitting between the second through hole 80b and the positioning projection 104, the inside of the cavity 102 of the resin r is determined. There is no concern that positional displacement will occur due to fluid pressure. When the molding is completed and the mold is removed, the porous body 8 is securely integrated into the support body 7 at a predetermined position (fitted into the recess 7aa), as shown in FIG. 10(a). Thus, a spacer 6 with high relative positional accuracy between the support body 7 and the porous body 8 can be obtained. The obtained spacer 6 is placed at an appropriate position in the arc-shaped portion 3a of the cooling water passage 3 provided in the cylinder block 1 as shown in FIGS. 1 to 3, and produces the above-mentioned functions and effects.
Note that this embodiment differs from the modification of the second embodiment shown in FIG. 5 in that the shape of the second through hole 80b is longer in the circumferential direction.

12 and 13 show a sixth embodiment of a spacer according to the present invention. In all of the above, the bottom surface of the bottomed part that closes the through hole 8a formed in the porous body 8 of the support body 7 (for example, in FIG. , FIG. 6 shows an example in which the recess 7d) is a flat surface. However, the present invention is not limited to this, and the bottom surface 7g may have a convex shape as shown in FIG. 13(b). Specifically, the bottom surface 7g is formed in a shape including a convex portion having an arcuate (hemispherical) cross section in a recess. The shape of the protrusion 7c itself is a cylindrical shape similar to the above embodiment.

Such a spacer 6 is manufactured by the steps shown in FIGS. 12(a), 12(b), and 13(a). First, FIG. 12A shows a step of transporting the porous body 8 placed on the lower mold 101 using the transport pins 106. A movable member 107 is attached to the conveyance pin 106 so as to move up and down along the conveyance pin 106 and to be movable together with the conveyance pin 106 . The movable member 107 is connected to a drive device (not shown). In the step shown in FIG. 12(a), a conveying pin 106 is inserted into the through hole 8a of the porous body 8 in a compressed state, and in this state, the porous body 8 is conveyed to above the lower mold 101 (FIG. (see (a)). Then, the tip 106a of the transfer pin 106 is fitted against the tip 102ab of the positioning protrusion 102aa provided on the lower mold 101, and the transfer pin 106 is fitted as shown in FIG. 12(b). The protrusion 102 is connected to the protrusion 102. With the conveying pin 106 and the protrusion 102aa connected in this manner, the porous body 8 is moved toward the protrusion 102aa, and the protrusion 102aa is inserted into the through hole 8a of the porous body 8. In this way, if the tip 102ab of the protrusion 102aa has a concave shape and the tip 106a of the conveyance pin 106 has a convex shape in accordance with the shape of the tip 102ab, the tip 102ab of the protrusion 102aa of the lower die 101 and the conveyor This facilitates alignment with the tip 106a of the pin 106. Then, the protrusion 102aa can be inserted into the through hole 8a of the porous body 8 efficiently and reliably.

Thereafter, the transfer pin 106 is moved by the movable member 107 so as to be separated from the protrusion 102aa, and the upper mold 103 is clamped to the lower mold 101 as shown in FIG. 13(a). In the subsequent steps, insert molding is performed in the same manner as in the above embodiment. When the molding is completed and the mold is removed, the porous body 8 is reliably integrated with the support body 7 at a predetermined position, and the spacer 6 is completed, as shown in FIG. 13(b). A cylindrical protrusion 7c communicating with the through hole 8a is formed on the support body 7 at a location corresponding to the through hole 8a of the porous body 8. Furthermore, a convex portion is formed on the bottom surface 7g of the bottom portion 7cc of the cylindrical protrusion 7c due to the shape of the bottomed hole portion 102ba and the shape of the tip portion 102ab of the protrusion 102aa. As a result, the opening 8aa of the through hole 8a is substantially closed by the support 7. The obtained spacer 6 is placed at an appropriate position in the arc-shaped portion 3a of the cooling water passage 3 provided in the cylinder block 1 as shown in FIGS. 1 to 3, and produces the above-mentioned functions and effects.

FIG. 14 shows a modification of the spacer described in the sixth embodiment. The shape of the bottom surface 7g of the bottomed portion of the support body 7 that closes the through hole 8a formed in the porous body 8 is not limited to the example shown in FIG. 13(b), but may be as shown in FIGS. It may be concave or convex. 14(a) to 14(d) are partially enlarged cross-sectional views in which only the protrusion 7a portion of the spacer 6 is enlarged.

In FIG. 14(a), the protrusion 7c has a conical shape with a triangular cross section. In this case, when installed in the cooling water flow path, the tips of the protrusions 7c come into point contact and do not impede the flow of cooling water, so it can be said that this shape is suitable for a place where the flow of cooling water is not desired to be suppressed.
Further, in the example shown here, the bottom surface 7g of the bottom portion 7cc of the support body 7 is also formed to have a triangular cross section.
In FIGS. 14(b) to 14(d), the shape of the protrusion 7c itself is a cylindrical shape similar to the above-described embodiment. However, in FIG. 14(b), the bottom surface 7g is formed in a triangular cross-sectional shape with the bottom surface 7g protruding in the opposite direction to that in FIG. 14(a) (protruding toward the porous body 8 side). In FIG. 14(c), the bottom surface 7g is formed in two stages, and is formed in a shape that includes a further recess within the recess. In FIG. 14(d), the bottom surface 7g is formed in a shape with a convex portion inside a recess.
In this way, the shape of the protrusion 7c that closes the opening 8aa of the through hole 8a of the porous body 8 is formed in consideration of controlling the flow of cooling water when installed in the cooling water flow path. Various types are adopted depending on the installation position when installed. Further, as shown here, in order to form the protrusion 7c, the above-described molding device 100 is formed with a bottomed hole 102ba and a protrusion 102aa according to the shape of the protrusion 7c. Further, the concave or convex shape shown in FIG. 13(b) or FIGS. 14(a) to (d) is not limited to the support body 7 having the protrusion 7c as shown in FIG. It may be provided on the support body 7 which is not provided with the support body 7, and in this case, it is provided on the bottom surface of the recessed portion 7d of the support body 7.
Since other functions and effects are the same as those of the other embodiments, the same reference numerals are given to the common parts (some illustrations are omitted), and the explanation thereof will be omitted here as well.

Note that the number, shape, and position of the protrusions 7c provided in the support body 7 and the through holes 8a provided in the porous body 8 are not limited to those illustrated, and may be changed as appropriate depending on cooling performance, etc., and required specifications, etc. Set. Although FIG. 5 shows an example in which the through holes 8a and the protrusions 7c are arranged in the circumferential direction of the cooling water flow path 3, for example, a plurality of the through holes 8a and the protrusions 7c are The spacers 6 may be formed so as to be arranged in the depth direction. Further, the structure in which the porous body 8 is embedded and attached to the recessed part of the support body 7 as shown in the second embodiment is not limited to partial spacers, but can also be used for semi-cylindrical supports as shown in the first embodiment. The present invention may be applied to the body 7, or may be applied to the entire cylindrical support extending around the entire circumference of the cooling water flow path 3. In addition to the cellulose sponge, the material constituting the porous body 8 may be a water-swellable sponge, a water-soluble binder, or a foam maintained in a compressed state by a binder that melts at a temperature higher than a predetermined temperature. It may also be made of a non-foaming porous material. Furthermore, the shapes of the groove portion 7e and the protruding portion 7f shown in the fourth embodiment are not limited to the illustrated example. The shape of the bottom portion 7g shown in FIGS. 13(b) and 14(a) to 14(d) is not limited to the illustrated example, and these shapes are similar to those in the first embodiment to the fifth embodiment. It may also be applied to the form. Further, the second through hole 80b shown in the fifth embodiment is not limited to the sheet-like porous body 8 that is long in the circumferential direction of the circular arc portion 70, but also the sheet-like porous body 8 that is short in the circumferential direction of the circular arc portion 70. may be provided.

Furthermore, various types of cellulose sponges may be mentioned, but are not particularly limited. For example, any of fine grains with very small bubbles, small grains with small bubbles, and medium grains with medium bubbles may be used. Specifically, a cellulose 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 sulfate used in the process of making the cellulosic sponge. 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 that retain cellulose hydroxyl groups to the extent that they can maintain a compressed state, such as cellulose ethers, cellulose esters, etc. The sponge may be selected from any of these mixtures.

In addition, the position at which the porous bodies 8 are fixed to the support body 7 (the position in the depth direction of the cooling water flow path 3, the position in the circumferential direction) and the number of porous bodies 8 (the position in the depth direction of the cooling water flow path 3) The number of spacers, the number in the circumferential direction) may be changed as appropriate depending on the required specifications, such as the stability of the spacer 6 within the cooling water flow path 3 or the cooling function of the cooling water flowing within the cooling water flow path 3. good. In the example shown in FIG. 1, the porous body 8 is provided for each arc-shaped portion of the support 7, but the porous body 8 is provided in a band-like manner corresponding to all (plural) arc-shaped portions of the support 7. The mass 8 may be attached to the support 7. Further, in FIG. 1, the shape of the support body 7 is exemplified as a semi-cylindrical (half-split) shape, but it may be a fully cylindrical shape that extends around the entire circumference of the cooling water flow path 3. Further, although the porous body 8 is attached to the inner surface 7a of the support 7, it may be attached to the outer surface 7b, or may be attached to both the inner surface 7a and the outer surface 7b of the support 7. . Furthermore, although a three-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 thereto and can be applied to internal combustion engines with other numbers of cylinders.

10 Internal combustion engine 1 Cylinder block 2 Cylinder bore 3 Cooling water passage 6 Spacer 7 Support body 7a Inner surface 7b Outer surface 7c Projection 7ca Opening 7e Groove 7g Bottom surface 70 Arc portion 8 Porous body 8a Through hole 8aa Opening 100 Molding device (molding mold)
102aa Protrusion d Circumferential direction

Claims (7)

A spacer disposed in a cooling water flow path provided in a cylinder block of an internal combustion engine so as to surround a cylinder bore, the spacer comprising:
a support made of synthetic resin;
a porous body attached to the inner or outer surface of the support by integral molding,
The porous body is provided with a through hole penetrating in the thickness direction thereof,
The support body is formed to close the opening of the through hole,
The support body is provided with a protrusion that protrudes on the opposite side from the porous body at a location corresponding to the through hole,
The protrusion is formed in a bottomed cylindrical shape that communicates with the through hole and has a closed opening on the opposite side of the porous body , and the support body disposed in the cooling water flow path is connected to the cooling water passage. A spacer characterized in that, when the spacer is displaced toward the inner wall surface of the water flow path, a tip thereof comes into contact with the inner wall surface . The spacer according to claim 1,
A spacer characterized in that a plurality of the through holes are provided, and the protrusion is provided at a location corresponding to each of the through holes. In the spacer according to claim 1 or claim 2,
A spacer characterized in that the support body is provided with a groove portion formed adjacent to the outer edge of the porous body on the side to which the porous body is attached. In the spacer according to any one of claims 1 to 3,
The spacer is characterized in that the porous body has a characteristic of expanding in the thickness direction from a compressed state when a predetermined external factor is applied. The spacer according to any one of claims 1 to 4,
The spacer is characterized in that the through hole is a hole through which a positioning protrusion for positioning the porous body in a mold is inserted when insert molding the porous body and the support body. The spacer according to claim 5,
The support body includes an arcuate portion corresponding to the cylinder bore,
The porous body is attached to the arc portion,
A first through hole constituting the through hole having a perfect circular shape is formed in the center of the porous body, and second through holes constituting the through hole are formed on both sides of the first through hole. has been
The spacer is characterized in that the second through hole is formed in a long hole shape that is longer in the circumferential direction of the circular arc portion than in the direction orthogonal to the circumferential direction of the circular arc portion. The spacer according to any one of claims 1 to 6,
The spacer is characterized in that the support body is formed with a bottomed portion that closes the opening of the through hole, and the bottom surface of the bottomed portion is formed in a concave shape or a convex shape.

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