OIL COOLER

Abstract

In an oil cooler, oil flow inlet and oil flow outlet are respectively opened on the laminated core itself at overlapped parts of a laminated core, the laminated core constituting a heat exchanger, and a base plate, with respect to at least one of the oil flow inlet and the oil flow outlet, a corresponding oil flow input or oil flow output port being formed on the base plate to be offset toward an outside of a projection configuration region of the laminated core and an oil passage is extended within the base plate to bridge over both of inside and outside of the projection configuration region of the laminated core to connect at least one of the oil flow inlet and the oil flow outlet to the corresponding oil flow input port of the base plate or oil flow output port of the base plate.

Description

BACKGROUND OF THE INVENTION

(1) Field of the Invention

The present invention relates to a structure of an oil cooler, for example, mounted in an engine block of an internal combustion engine equipped in a vehicle or mounted in a transmission casing of an automatic transmission equipped in the vehicle.

(2) Description of Related Art

A, so-called, laminated core type oil cooler in which a plurality of core plates are laminated in a multiple stage is a representative oil cooler of this kind. In such a laminated core type oil cooler as described above, a thick plate formed (namely, thick) base plate which functions as an attachment section of the laminated core plates to a mating equipment (for example, the mating equipment is constituted by an engine block or a transmission casing) is installed at a lowest stage (nearest to an attachment surface of the mating equipment) of the laminated cores which are core plate laminating bodies. In a case where an attention has been only paid to a flow of a cooled medium such as oil, supply and reception of oil and so forth are directly carried out between the mating equipment through flow holes formed on the base plate.

On the other hand, due to a restraint on a layout of the mating equipment, positions of an oil flow-in hole and an oil flow-out hole of the oil cooler are not always coincident with positions of the oil flow-out hole and the oil flow-in hole of the mating equipment. In such a case as described above, an elongated hole shaped passage which traverses within two sheet structured base plate as described in a first previously proposed oil cooler disclosed in a Japanese Patent Application First Publication No. 2010-060168 published on Mar. 18, 2010 or the similar passage is needed to be installed on a seated surface of the mating equipment as described in a second previously proposed oil cooler disclosed in a Japanese Patent Application First Publication No. 2010-265861 published on Nov. 25, 2010 (which corresponds to an European Patent Application Publication No. EP 2 253 811). Thus, a continuity of passage between the oil cooler and the mating equipment is assured.

SUMMARY OF THE INVENTION

However, in the structure of oil cooler described in the first previously proposed oil cooler, both of the flow-out hole and the flow-in hole at the mating equipment in addition to the flow-in hole and the flow-out hole at the oil cooler side are assumed to be within a projection configuration region of the laminated core in a core plate laminated direction, a desired object cannot be accomplished in a case where positions of the flow-out hole and flow-in hole at the mating equipment are, for example, set at an outside of the projection configuration region of the laminated core due to the restraint of the lay out of the mating equipment.

In the structure of the oil cooler described in the Japanese Patent Application First Publication No. 2010-265861, as is different from that described in the Japanese Patent Application First Publication No. 2010-060168, the desired object can be accomplished even though positions of the flow-out hole and the flow-in hole at the mating equipment are set at the outside of the projection configuration region of the laminated core. However, it is necessary to perform a groove machining or so forth which is to be a passage for the mating equipment which has the restraint on the layout and a manufacturing cost is accordingly compelled to be increased. In addition, since a region to be sealed by means of a seal ring is necessarily increased along with the groove machining to form the passage, it is necessary to simultaneously machine the seal ring groove to accept the seal ring. Therefore, a higher manufacturing cost is compelled to be increased. Especially, it is not favorable that the structure of the seated surface corresponding section of the mating equipment becomes complicated.

It is, therefore, an object of the present invention to provide a structure of an oil cooler which is capable of accomplishing the desired object described above especially without introductions of the complication of the structure of the mating equipment and of the increase in the manufacturing cost.

According to one aspect of the present invention, there is provided with an oil cooler comprising: a laminated core including a multiple number of plates laminated to form alternately a coolant chamber and an oil chamber between the mutually adjacent plates, the laminated core functioning to be a heat exchanger; a base plate on which the laminated core is overlapped and having a configuration larger than a projection configuration region of the laminated core in a plate lamination direction of the laminated core, the base plate functioning to be an attachment section of the laminated core to a mating equipment; oil flow input and output ports respectively opened at an attachment surface of the base plate to the mating equipment and connected to oil passages of the mating equipment opened at a seated surface of the mating equipment to the base plate; oil flow inlet and oil flow outlet respectively opened on the laminated core itself at overlapped parts of the laminated core and the base plate, with respect to at least one of the oil flow inlet and the oil flow outlet, the corresponding oil flow input or oil flow output port being formed on the base plate to be offset toward an outside of the projection configuration region of the laminated core; and an oil passage extended within the base plate to bridge over both of inside and outside of the projection configuration region of the laminated core to connect at least one of the oil flow inlet and the oil flow outlet to the corresponding oil flow input port of the base plate or oil flow output port of the base plate.

According to another aspect of the present invention, there is provided with an oil cooler, comprising: a heat exchanger constituted by a plurality of plates laminated to form alternately a plurality of coolant chambers and a plurality of oil chambers, each coolant chamber being connected to coolant input and output pipes and each oil chamber being connected to a corresponding one of oil passages of a mating equipment mounted in a vehicle; a plate form attachment section configured to attach the heat exchanger onto the mating equipment, the plate form attachment section being overlapped with the heat exchanger and having a configuration larger than a projection configuration region of the heat exchanger in a plate form lamination direction of the heat exchanger; oil flow input and output ports respectively opened at an attachment surface of the plate form attachment section to the mating equipment and connected to the oil passages of the mating equipment which are opened at a seated surface of the mating equipment; and oil flow inlet and outlet respectively opened on the heat exchanger through which oil is caused to flow into and out of each oil chamber of the heat exchanger, a position of at least one of the oil flow input and output ports of the plate form attachment section being offset from the corresponding one of the oil flow inlet and outlet of the heat exchanger toward an external to the projection configuration region and the plate form attachment section having an oil passage extended over both of internal and external to the projection configuration region of the heat exchanger to connect at least one of the oil flow inlet and outlet to the corresponding one of the oil flow and output ports of the plate form attachment section.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view of an oil cooler representing a first preferred embodiment according to the present invention.

FIG. 2 is a bottom view of an oil cooler shown in FIG. 1.

FIG. 3 is a cross sectional view of the oil cooler cut away along a line A-A in FIG. 1.

FIG. 4 is an exploded perspective view of the oil cooler shown in FIG. 3.

FIG. 5 is an essential part expanded view of a fin plate of the oil cooler shown in FIGS. 3 and 4.

FIG. 6 is an explanatory view representing a flow of oil at a part corresponding to a cross section cut away along a lien A-A in FIG. 1.

FIG. 7 is an explanatory view representing a flow of a coolant at a part corresponding to a cross section cut away along a line B-B in FIG. 1.

FIG. 8 is an essential part cross sectional view of the oil cooler representing a second preferred embodiment according to the present invention.

FIG. 9 is an essential part cross sectional view of the oil cooler representing a third preferred embodiment according to the present invention.

FIG. 10 is an essential part cross sectional view of the oil cooler representing a fourth preferred embodiment according to the present invention.

FIG. 11 is an essential part cross sectional view of the oil cooler representing a fifth preferred embodiment according to the present invention.

FIG. 12 is an essential part cross sectional view of the oil cooler representing a sixth preferred embodiment according to the present invention.

FIG. 13 is an essential part cross sectional view of the oil cooler representing a seventh preferred embodiment according to the present invention.

FIG. 14 is an essential part cross sectional view of the oil cooler representing an eighth preferred embodiment according to the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Reference will, hereinafter, be made to the drawings in order to facilitate a better understanding of the present invention. FIGS. 1 through 7 show a first preferred embodiment of an oil cooler according to the present invention. FIG. 1 shows a plan view of the oil cooler and FIG. 2 shows a bottom view of the oil cooler, respectively. In addition, FIG. 3 shows a cross sectional view of the oil cooler cut away along a line A-A in FIG. 1 as an attachment state of the oil cooler and FIG. 4 shows an exploded view of the same oil cooler.

As shown in FIGS. 1, 2, and 3, oil cooler 1 is constituted by a laminated core 3 which is a lamination of core plates 5, 5, . . . , fin plates 6, 6, . . . , and embossed plates 7, 7, . . . (as will be described later) with a predetermined regularity and by a base plate 2 of a two-layer structure disposed at a lower side of laminated core 3 so as to be overlapped on the lower side of laminated core 3. While laminated core 3 functions as a heat exchanger as will be described later, base plate 2 functions as an attachment flange section to a transmission casing 4 of, for example, an automatic transmission as a mating equipment. As appreciated from FIGS. 1 and 3, laminated core 3 is of an approximately square shape in a plan view (as viewed from a top) and, on the other hand, base plate 2 is formed to have a larger polygon shape than the projection configuration of laminated core 3.

It should be noted that all of components of oil cooler 1 are made of aluminum and the mating equipment may be an engine block or an oil pan of an internal combustion engine.

Laminated core 3 is, as shown in FIGS. 3 and 4, constituted by three components of thin plate core plates 5 having holes, fin plate 6, and embossed plate 7 on which a multiple number of fine embossed sections are formed and having the holes as one group, these three components being laminated over n stages (n denotes a natural number and, in the case of FIG. 3, n is four). In addition, for an uppermost stage of the groups of the plate structure, another core plate 8 having the holes is laminated in place of embossed plate 7 and a top plate 9 is laminated over other core plate 8. Furthermore, a coolant (cooling water) input pipe 10 and a coolant (cooling water) output pipe 11 are, respectively, connected to top plate 9. These pipes 10, 11 are connected to a water jacket of the engine or so forth.

In addition, each of fin plates 6 is depicted in such a thin plate shape as a case of FIG. 4 but is, actually, formed by bending in a, so-called, corrugated fin shape as shown in FIG. 5. Junctions of mutual plates shown in FIG. 4 forming laminated core 3 and the junction of top plate 9 with each pipe 10, 11 are carried out by brazing.

In such a plate structure as described above, an oil chamber 12 is formed to include fin plate 6 between core plate 5 and embossed plate 7 and a coolant chamber 13 is formed between embossed plate 7 and core plate 5, as appreciated from FIGS. 3 and 6. In other words, oil chamber 12 and coolant chamber 13 are alternatively formed for each one stage in the lamination direction of each plate in laminated core 3. Thus, laminated core 3 functions as a heat exchanger with oil as a cooled medium and with coolant (cooling water) as a cooling medium. It should be noted that FIG. 6 shows a direction of oil in laminated core 3 in the cross section cut away along line A-A in FIG. 1.

In addition, embossed sections 15, 15 are previously formed on peripheral edges of a pair of holes 14 formed on a diagonal line of each embossed plate 7 and these embossed sections 15 are brazed to lower surface parts of peripheral edge sections of a pair of holes 16 formed on the diagonal line of each core plate 5 located above the corresponding one of embossed plate 7 (refer to FIG. 4). Thus, as shown in FIGS. 3 and 6, communication passages 17, 18 to communicate respective oil chambers 12 are formed in laminated core 3 in a direction in which laminated core is cut vertically. Then, oil is directed from one communication passage 17 toward other communication passage 18 via respective oil chambers 12.

The structure of communication passages described above is basically the same as that in the case of the coolant (cooling water) side. That is to say, embossed sections 20 are previously formed on peripheral edge sections of a pair of holes 19 formed on the diagonal line of each core plate 5 and these embossed sections 20 are brazed to lower surface parts of peripheral edge sections of a pair of holes 21 formed on the diagonal line of each core plate 5 located above the corresponding one of embossed plate 7 (refer to FIG. 4). Thus, at a portion of laminated core 3, communication passages 22, 23 to communicate respective coolant chambers 13 are formed in a direction in which laminated core 3 is vertically cut as shown in FIG. 7 and the coolant introduced from coolant input pipe 10 is directed from one communication passage 22 to the other communication passage 23 via respective coolant chambers 13.

It should be noted that the structure of laminated core 3 described above according to the plate structure is, basically the same as described in the Japanese Patent Application First Publication No. 2010-060168 described in the BACKGROUND OF THE INVENTION.

Base plate 2 is, as shown in FIGS. 1. 3, and 4, constituted by a base plate main frame 24 which is one plate element placed at an opposite side to laminated core 3 and a distance plate 25 overlapped on base plate main plate 24 which is the other plate element placed at the side of laminated core 3. Both of these base plate main frame 24 and distance plate 25 are brazed together. Laminated core 3 is similarly brazed onto distance plate 25. Especially, as appreciated from FIG. 3, both of thickness and shape of base plate main frame 24 are set to be larger than those of distance plate 25. A bolt 27 is inserted into each attachment hole 26 to fix base plate 2 to transmission casing 4 which is the mating equipment.

An oil passage 28 which provides an oil flow output side through which oil within oil chambers 12 is caused to flow out and an oil passage 29 which provides an oil flow output side through which oil within oil chambers 12 is caused to flow in and oil passage 29 through which oil within transmission casing 4 is caused to flow toward oil chambers 12 is opened on seated surface 4a of transmission casing 4 on which oil cooler 1 described above is attached. Then, flow output side oil passage 28 is connected with oil flow inlet 30 located at the lowest surface of laminated core 3 and flow input side oil passage 29 is connected with oil flow outlet 31 located at the lowest surface of laminated core 3, respectively. It should be noted that either one of the pair of holes 16 formed on the lowest stage of core plates 5 corresponds to oil flow inlet 30 and the other of pair of holes 16 corresponds to oil flow outlet 31.

As appreciated from FIG. 3, a span formed between flow output side oil passage 28 and flow input side oil passage 29 is set to be larger than the span formed between oil flow inlet 30 and oil flow outlet 31 at laminated core 3 side and flow input side oil passage 29 is set to be coincident with oil flow outlet 31 in a region of a projection configuration (a projection configuration in the lamination direction of each plate constituting laminated core 3) of laminated core 3. On the other hand, flow output side oil passage 28 is not set within the region of the projection configuration of laminated core 3 but is set at an outside of the projection configuration region so as to be offset largely from oil flow inlet 30.

When flow output side oil passage 28 is connected to oil flow inlet 30 on the lowest surface of laminated core 3 and flow input side oil passage 29 is connected to oil flow outlet 31 on the lowest surface of laminated core 3, respectively, in addition to the difference in magnitude between the spans described above, a function to be compensated for an offset quantity of flow output side oil passage 28 with respect to oil flow inlet 30 at laminated core 3 side is provided for base plate 2.

More specifically, as appreciated from FIG. 3, in a state in which oil cooler 1 is fixed to a normal (or a predetermined) position of transmission casing 4 which is the mating equipment by means of bolts 27, oil flow outlet 31 at laminated core 3 side is set so that oil flow outlet 31 at laminated core side 3 is positionally set to be coincident with flow input side oil passage 29 at the transmission casing 4 side. In order to connect these oil flow outlet 31 and oil flow input side oil passage 29, oil flow output ports 32, 32 which are penetrated in plate thickness directions of base plate main frame 24 and distance plate 25 and which are opened on attachment surface 24a to transmission casing 4 (refer also to FIG. 4). In addition, an annular groove section 33 which is concentric to oil flow output ports 32 and which surrounds oil output port 32 is formed on attachment surface 24a (also refer to FIG. 2) of base plate main frame 24. An O ring 34 as a seal member which is fitted and retained in annular groove section 33 serves to seal its connection section between base plate main frame 24 and transmission casing 4.

Since flow output side oil passage 28 at transmission casing 4 side with respect to oil flow inlet 30 of laminated core 3 is largely offset toward the outside of the projection configuration region of laminated core 3, both of oil flow inlet 30 and flow output side oil passage 28 are connected together via an oil passage 35 formed between base plate main frame 24 and distance plate 25 constituting base plate 2. This oil passage 35 is extended over both of inside and outside of the projection configuration region to connect between oil flow inlet 30 at laminated core 3 side and flow output side oil passage 28 at transmission casing 4 side.

In more details, as shown in FIGS. 3 and 4, an inner communication port 36 is formed on distance plate 25 as one plate element of laminated core 3 side at a position at which inner communication port 36 is coincident with oil flow inlet 30 at laminated core 3 side and elongated hole shaped and groove shaped inner passage section 37 which is mated or overlapped with inner communication port 36 and which is extended between both of inner and outer projection configuration region of laminated core 3 is formed on base plate main frame 24 which is the other plate element at the opposite side of laminated core 3. This inner passage section 37 is formed, for example, by machining through an end mill or by coining with a use of a press.

In addition, a bead-shaped embossed section 38 is protruded from distance plate 25 at the outside of the projection configuration region of laminated core 3 and on an extension line of inner passage section 37 at base plate main frame 24 side. Thus, this embossed section 38 is offset with inner passage section 37 in the plate thickness direction of base plate 2 but is partially overlapped on and communicated with inner passage section 37 and an elongated hole shaped outer passage section 39 is extended toward an anti-projection configuration region (an opposite side of the projection configuration region) of laminated core 3, namely, so as to be overlapped on flow output side oil passage 28 of transmission casing 4 side.

Furthermore, an oil flow input port 40 is opened and formed which is penetrated in the plate thickness direction of base plate main frame 24 to open at attachment surface 24a to transmission casing 4. An annular groove section 41 which is concentric to this oil flow in port 40 is formed on attachment surface 24a so as to surround oil flow in port 40. An O ring 42 as a seal member which is fitted and retained in annular groove section 41 serves to seal its connection section between base plate main frame 24 and transmission casing 4.

Hence, according to oil cooler 1 configured in the way described above, as appreciated from FIG. 3, even if the span formed between flow output side oil passage 28 at transmission casing 4 side (which is the mating equipment) and flow input side oil passage 29 is larger than the span formed between oil flow inlet 30 and oil flow outlet 31 at laminated core 3 side and flow output side oil passage 30 and flow input side oil passage 28 is largely offset from oil flow inlet 30 of laminated core 3 side at the outside of the projection configuration region of laminated core 3, oil passage 35 required for the supply and reception of oil between oil cooler 1 and mating equipment such as transmission casing 4 can be secured with no forcible effort without carrying out a groove machining on seated surface 4a of transmission casing 4.

Especially, outer passage section 39 which is a part of oil passage 35 is formed with embossed section 38 which is a protrusion of a part of distance plate 25 which is the one plate element and part of embossed section 38 and the seal section constituted by O ring 42 are overlapped together in the plate thickness direction so that a total thickness of base plate 2 is partially large. However, since embossed section 38 is set on base plate 2 at the outside of the projection configuration region of laminated core 3, a protrusion height of embossed section 38 gives no influence on a total thickness of base plate 2 in the projection configuration region of laminated core 3, namely, the total thickness of base plate 2 just below laminated core 3. Therefore, the thickness of base plate 2 just below laminated core 3 and, in turn, a height of whole oil cooler 1 including laminated core 3 in addition to base plate 2 can be suppressed. The restraint on layout of the position at which oil cooler 1 is to be installed can be relieved and the height of whole oil cooler 1 can contribute on an improvement on easiness of mounting of oil cooler 1 in the vehicle or so forth.

In addition, when oil cooler 1 described above is applied to the mating equipment having the different specification of span formed between flow output side oil passage 28 and flow input side oil passage 29, a specification on base plate 2 to be combined with laminated core 3 may be modified. Thus, a easier correspondence to the different span can be made.

FIG. 8 shows a second preferred embodiment of oil cooler 1 according to the present invention and FIG. 9 shows a third preferred embodiment of oil cooler 1 according to the present invention. It should be noted that the same reference numerals are designated for the like elements shown in FIG. 3.

In the second embodiment shown in FIG. 8, base plate main frame 44 constituting base plate 2 is partially supported by transmission casing 4 without whole surface contact of base plate main frame 44 against transmission casing 4 which is the mating equipment.

For example, a case where a tightening section by means of bolts 27 in addition to flow output side oil passage 28 and flow input side oil passage 29 is set on a boss section 4b projected from a general section of transmission casing 4 is supposed. On the above-described supposition, as shown in FIG. 8, an embossed section 48 is protruded on base plate main frame 44 constituting base plate 2 together with distance plate 25 toward a downward direction.

Consequently, an elongated hole shaped space as inner passage section 37 which is a part of oil passage 35 is secured.

In a case of the third embodiment shown in FIG. 9, on an assumption of the same structure as FIG. 8, base plate main frame 54 is set to be thinner than that (48) in the case of FIG. 8 and an annular groove section 51 housing O ring 42 which is the seal member is formed on seated surface 4a of boss section 4b.

The same advantages as those in the case of the first embodiment can be obtained in these second and third embodiments. In addition, a passage cross sectional area of inner passage section 37 can sufficiently be secured. Especially, in the third embodiment shown in FIG. 9, the total thickness of base plate 2 can be smaller (thinner) according to the thin plating of base plate main frame 54 and the weight of base plate 2 can be lighter although it is necessary to carry out a machining of annular groove section 51 of transmission casing 4 side.

FIG. 10 shows a fourth preferred embodiment of the oil cooler according to the present invention. FIG. 11 shows a fifth preferred embodiment of the oil cooler according to the present invention. FIG. 12 shows a sixth preferred embodiment of the oil cooler according to the present invention. The same reference numerals are designated for the like elements common to FIG. 3.

In the fourth embodiment shown in FIG. 10, distance plate 65 is made thicker than distance plate 25 shown in FIG. 3, distance plate 65 constituting base plate 2 together with base plate main frame 64. In place of forming inner passage section 37 on base plate main frame 64 (as shown in FIG. 3), an elongated hole shape oil passage 55 is formed on distance plate 65 together with inner communication port 36 by a coining with a use of a press or by machining. This oil passage 55 has no offset in the plate thickness direction of base plate 2 as is different from FIG. 3.

In the fifth embodiment shown in FIG. 11, in place of forming inner passage section 37 as shown in FIG. 3 on base plate main frame 64, an embossed section 58 is protruded from distance plate 75 toward flow output side oil passage 28 located at the outside of the projection configuration region of laminated core 3. Thus, the elongated hole shaped space as oil passage 85 together with inner communication port 36 is secured. This oil passage 85 has no offset in the plate thickness direction of base plate 2 as is different from that in the case of FIG. 3.

In the sixth preferred embodiment shown in FIG. 12, in place of protruding embossed section 68 in the downward direction from the projection configuration region of laminated core 3 toward flow output side oil passage 28 which is outside of the projection configuration region from base plate main frame 74 as is different from FIG. 3 so that the elongated hole shaped space is secured as oil passage 105 and only inner communication port 36 is formed on distance plate 95. This oil passage 105 has no offset in the plate thickness direction of base plate 2 as is different from that shown in FIG. 3.

The similar advantages as those in the case of the first embodiment representatively shown in FIG. 3 can be obtained in the case of the fourth, fifth, and sixth embodiments.

FIG. 13 shows a seventh preferred embodiment of oil cooler according to the present invention and FIG. 14 shows an eighth preferred embodiment according to the present invention. The same reference numerals are designated for the like elements common to FIG. 3.

In the seventh embodiment shown in FIG. 13, in place of forming outer passage section 39 by the use of embossed section 38 as shown in FIG. 3, an elongated hole shaped outer passage section 49 is formed on distance plate 115 to be penetrated in the plate thickness direction of distance plate 115 and is partially sealed with another cover plate 125. It should be noted that cover plate 125 constituting base plate 2 is joined on distance plate 115 by means of, for example, brazing.

According to the seventh embodiment shown in FIG. 13, base plate 2 is partially of the, so-called, three-ply structure. However, as compared with base plate 2 formed through the embossing, it is easy in securing outer passage section 49. Since thin plate cover plate 125 is used, the total thickness of base plate 2 at least at a part of base plate corresponding to outer passage section 49 can advantageously be made small.

In the eighth embodiment shown in FIG. 14, base plate 2 itself has substantially the three-ply structure by the use of both of a first distance plate 135 and a second distance plate 145 in addition to base plate main frame 64 as one of the plate elements of base plate 2. Then, an elongated hole shaped oil passage 155 is formed which is penetrated from first distance plate 135 toward flow output side oil passage 28 located at the outside of the projection configuration region of laminated core 3. On the other hand, inner communication port 36 is formed on second distance plate 145. Elongated hole shaped oil passage 155 at second distance plate 135 side is sealed by second distance plate 145. This oil passage 155 has no offset in the plate thickness direction of base plate 2 as is different from FIG. 3.

According to the eighth preferred embodiment, although the number of plates as the plate elements constituting base plate 2 is three, the pressing for the respective plate elements can advantageously be facilitated.

It should, herein, be noted that, in each embodiment described above, oil flow inlet 30 and flow output side oil passage 28 at transmission casing 4 side which is offset from oil flow inlet 30 are interconnected via oil passage 35. However, the present invention is, of course, applicable to a case where oil flow outlet 31 and flow input side oil passage 29 are offset.

In addition, depending upon the specification of oil cooler 1 or the relationship with the mating equipment, as the oil flow within the oil cooler, the flow of oil introduced from oil flow inlet 30 via oil flow input port 40 and inner passage section 37 shown in FIG. 3 is folded back toward an inside of top plate 9 and is caused to flow out to the mating equipment utilizing effectively hole section H penetrated at the center section of laminated core 3 shown in FIGS. 1 and 3. In this case, oil flow out port 32 is needed to be formed at a position coincident with hole section H. It is of course that the present invention is applicable to the oil cooler described above.

Technical concepts derived from the present invention will be described in details below. That is to say, an oil cooler comprises: a laminated core including a multiple number of plates laminated to form alternately a coolant chamber and an oil chamber between the mutually adjacent plates, the laminated core functioning to be a heat exchanger; a base plate on which the laminated core is overlapped and having a configuration larger than a projection configuration region of the laminated core in a plate lamination direction of the laminated core, the base plate functioning to be an attachment section of the laminated core to a mating equipment; oil flow input and output ports respectively opened at an attachment surface of the base plate to the mating equipment and connected to oil passages of the mating equipment opened at a seated surface of the mating equipment to the base plate; oil flow inlet and oil flow outlet respectively opened on the laminated core itself at overlapped parts of the laminated core and the base plate, with respect to at least one of the oil flow inlet and the oil flow outlet, the corresponding oil flow input or oil flow output port being formed on the base plate to be offset toward an outside of the projection configuration region of the laminated core; and an oil passage extended within the base plate to bridge over both of inside and outside of the projection configuration region of the laminated core to connect at least one of the oil flow inlet and the oil flow outlet to the corresponding oil flow input port of the base plate or oil flow output port of the base plate.

It should, herein, be noted that the base plate may be formed of a single sheet of plate element or may be formed of plural sheets of plate elements.

In the latter case, in order to reduce the total thickness size (dimension) of the base plate at least in the projection configuration region of the laminated core as small as possible, as described in the claim 1, it is desirable that the base plate is formed with at least two sheets of mutually overlapped plate elements and the oil passage of the base plate is formed between the two sheets of plate elements.

More desirably, as described in the claim 3, the oil passage of the base plate includes: an inner passage section located near to the projection configuration region of the laminated core; and an outer passage section located nearer to an opposite side of the projection configuration region of the laminated core than the inner passage section and located near to the laminated core with respect to a plate thickness direction of the base plate, both of the inner and outer passage sections being communicated with each other and being offset from each other in the plate thickness direction of the base plate.

Specifically, as described in the claim 4, the outer passage section is formed on one of the two sheets of the plate elements at the laminated core side and the inner passage section is formed on the other of the two sheets of plate elements at the opposite side of the laminated core, respectively.

More specifically, as described in the claim 5, an inner communication port connecting either the oil flow inlet or the oil flow outlet to the inner passage section and the outer passage section are formed on one of the plate elements located at the laminated core side and the oil flow input port connecting one of the oil passages of the mating equipment to the outer passage section and the inner passage section are formed on the other of the plate elements located at an opposite side of the laminated core.

Hence, as the invention described in at least one claim 1, the oil passage extended over both of the inside and outside of the projection configuration of the laminated core is formed in the base plate. Thus, due to the restraint of the layout of the mating equipment, with respect to the position of the oil flow input port of the oil cooler side or the oil flow output port of the oil cooler side is not coincident with the position of the corresponding oil passage of the mating equipment to the oil flow input port or the oil flow output port so that, even if the position of the oil passage of the mating equipment is set toward the outside of the projection configuration region of the laminated core, it is possible to accomplish the desired object. Therefore, it becomes unnecessary to form the groove section (as is described in the second previously proposed oil cooler described in the BACKGROUND OF THE INVENTION) on the seated surface of the mating equipment.

This application is based on a prior Japanese Patent Application No. 2011-026753 filed in Japan on Feb. 10, 2011. The entire contents of this Japanese Patent Application No. 2011-026753 are hereby incorporated by reference. Although the invention has been described above by reference to certain embodiments of the invention, the invention is not limited to the embodiment described above. Modifications and variations of the embodiments described above will occur to those skilled in the art in light of the above teachings. The scope of the invention is defined with reference to the following claims.

Claims

1. An oil cooler comprising:

a laminated core including a multiple number of plates laminated to form alternately a coolant chamber and an oil chamber between the mutually adjacent plates, the laminated core functioning to be a heat exchanger;

a base plate on which the laminated core is overlapped and having a configuration larger than a projection configuration region of the laminated core in a plate lamination direction of the laminated core, the base plate functioning to be an attachment section of the laminated core to a mating equipment;

oil flow input and output ports respectively opened at an attachment surface of the base plate to the mating equipment and connected to oil passages of the mating equipment opened at a seated surface of the mating equipment to the base plate;

oil flow inlet and oil flow outlet respectively opened on the laminated core itself at overlapped parts of the laminated core and the base plate, with respect to at least one of the oil flow inlet and the oil flow outlet, the corresponding oil flow input or oil flow output port being formed on the base plate to be offset toward an outside of the projection configuration region of the laminated core; and

an oil passage extended within the base plate to bridge over both of inside and outside of the projection configuration region of the laminated core to connect at least one of the oil flow inlet and the oil flow outlet to the corresponding oil flow input port of the base plate or oil flow output port of the base plate.

2. The oil cooler as claimed in claim 1, wherein the base plate is formed with at least two sheets of mutually overlapped plate elements and the oil passage of the base plate is formed between the two sheets of plate elements.

3. The oil cooler as claimed in claim 2, wherein the oil passage of the base plate includes: an inner passage section located near to the projection configuration region of the laminated core; and an outer passage section located nearer to an opposite side of the projection configuration region of the laminated core than the inner passage section and located near to the laminated core with respect to a plate thickness direction of the base plate, both of the inner and outer passage sections being communicated with each other and being offset from each other in the plate thickness direction of the base plate.

4. The oil cooler as claimed in claim 3, wherein the outer passage section is formed on one of the two sheets of the plate elements at the laminated core side and the inner passage section is formed on the other of the two sheets of plate elements at the opposite side of the laminated core, respectively.

5. The oil cooler as claimed in claim 4, wherein an inner communication port connecting either the oil flow inlet or the oil flow outlet to the inner passage section and the outer passage section are formed on one of the plate elements located at the laminated core side and the oil flow input port connecting one of the oil passages of the mating equipment to the outer passage section and the inner passage section are formed on the other of the plate elements located at an opposite side of the laminated core.

6. The oil cooler as claimed in claim 1, wherein the mating equipment is a transmission casing of an automatic transmission mounted in a vehicle.

7. The oil cooler as claimed in claim 6, wherein the oil flow input port of the base plate is offset with respect to the corresponding oil flow inlet) of the laminated core toward the outside of the projection configuration region of the laminated core.

8. The oil cooler as claimed in claim 7, wherein a base plate main frame constituting the base plate and located at the opposite side of the laminated core is partially supported by the transmission casing.

9. The oil cooler as claimed in claim 8, wherein the base plate main frame is embossed and protruded toward an inside of the transmission casing and joined with a boss section of the transmission casing.

10. The oil cooler as claimed in claim 7, wherein an inner communication port connecting the oil flow inlet to the oil passage of the base plate is integrally formed with the oil passage of the base plate connected directly between the inner communication port and the oil flow inlet port without an offset of the oil passage of the base plate in a plate thickness direction of the base plate.

11. The oil cooler as claimed in claim 10, wherein the base plate comprises: an embossed section protruded from the projection configuration region of the laminated core toward one of the oil passages of the transmission casing through which oil is caused to flow toward the oil flow input port; and a base plate main frame on which the oil flow input port is formed.

12. The oil cooler as claimed in claim 10, wherein the base plate comprises: an embossed section formed on a base plate main frame of the base plate and protruded from the projection configuration region of the laminated core toward one of the oil passages through which oil is caused to flow toward the oil flow input port and a distance plate on which only the inner communication port is formed.

13. The oil cooler as claimed in claim 7, wherein the oil passage of the base plate comprises: an inner passage section located near to the projection configuration region of the laminated core; an outer passage section located nearer to an opposite side of the projection configuration region of the laminated core than the inner passage section and located near to the laminated core with respect to a plate thickness direction of the base plate, both of the inner and outer passage sections being communicated with each other and being offset from each other in the plate thickness direction of the base plate and an inner communication port connecting the oil flow inlet to the inner passage section is formed on the base plate.

14. The oil cooler as claimed in claim 13, wherein the base plate comprises a cover plate, a distance plate on which the inner communication port is formed, and a base plate main frame located at the seated surface of the transmission casing, the outer passage section being formed between the cover plate and the outer passage and the inner passage section being formed between the distance plate and the base plate main frame.

15. The oil cooler as claimed in claim 10, wherein the base plate comprises a base plate main frame located at the seated surface of the transmission casing, a first distance plate, and a second distance plate located at the laminated core side, the inner communication port being formed on the second distance plate and the oil passage of the base plate being defined by the first distance plate, the second distance plate, and the base plate main frame.

16. An oil cooler, comprising:

a heat exchanger constituted by a plurality of plates laminated to form alternately a plurality of coolant chambers and a plurality of oil chambers, each coolant chamber being connected to coolant input and output pipes and each oil chamber being connected to a corresponding one of oil passages of a mating equipment mounted in a vehicle;

a plate form attachment section configured to attach the heat exchanger onto the mating equipment, the plate form attachment section being overlapped with the heat exchanger and having a configuration larger than a projection configuration region of the heat exchanger in a plate form lamination direction of the heat, exchanger;

oil flow input and output ports respectively opened at an attachment surface of the plate form attachment section to the mating equipment and connected to the oil passages of the mating equipment which are opened at a seated surface of the mating equipment; and

oil flow inlet and outlet respectively opened on the heat exchanger through which oil is caused to flow into and out of each oil chamber of the heat exchanger, a position of at least one of the oil flow input and output ports of the plate form attachment section being offset from the corresponding one of the oil flow inlet and outlet of the heat exchanger toward an external to the projection configuration region and the plate form attachment section having an oil passage extended over both of internal and external to the projection configuration region of the heat exchanger to connect at least one of the oil flow inlet and outlet to the corresponding one of the oil flow and output ports of the plate form attachment section.