Oil cooler for vehicle

An oil cooler for a vehicle may include a header tank partitioned by a diaphragm formed at an inside of a center in a length direction thereof, and adapted to take in a working fluid at a first side and to take out the working fluid at a second side with respect to the diaphragm, a connection tank disposed to be spaced apart from the header tank by a predetermined interval, a plurality of tubes mounted along a length direction at an interior surface of the header tank to connect with the connection tank such that the working fluid flows therethrough, and a bypass valve integrally mounted at an outside of the header tank and connected to the inside of the header tank so as to bypass or flow the working fluid flowing therein into the inflow tank by selectively opening/closing according to a temperature of the working fluid.

CROSS-REFERENCE TO RELATED APPLICATION

The present application claims priority to Korean Patent Application No. 10-2014-0163764 filed Nov. 21, 2014, the entire contents of which is incorporated herein for all purposes by this reference.

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to an oil cooler for a vehicle. More particularly, the present invention relates to an oil cooler for a vehicle of which a bypass valve, which is operated according to a temperature of a working fluid, is integrally provided.

Description of Related Art

Generally, an oil cooler for cooling transmission oil is a device which is provided to maintain the temperature of the transmission oil at a predetermined temperature such that it is not excessively increased by slip of transmission friction components, and such that fuel consumption is not deteriorated as friction loss is increased when oil viscosity increases by excessive cooling of the transmission oil. In addition, a conventional oil cooler is divided into an air-cooling type and a water-cooling type.

Among them, an air-cooling type of oil cooler includes an oil cooler provided at a location such as a front of a radiator at which the outside air smoothly flows, and a bypass valve that is installed in a pipe which is connected to the transmission to be opened and closed depending on the temperature of the transmission oil.

The bypass valve maintains the transmission oil at the predetermined temperature, such that when the temperature of the transmission oil is higher than the predetermined temperature, the transmission oil is caused to pass through the oil cooler via the bypass valve, and when the temperature of the transmission oil is lower than the predetermined temperature, the transmission oil is not allowed to pass through the oil cooler thereby flowing back into the transmission.

However, since the conventional oil cooler has the bypass valve that is connected to the transmission to be opened and closed depending on the temperature of the transmission oil as described above, and is installed in a pipe that connects the transmission and the oil cooler, because a relatively large bypass valve is located in the pipe, there is also a drawback that the piping layout is complicated, such that spatial utility of an engine compartment is degraded.

Furthermore, with the bypass valve applied to the conventional oil cooler as described above, since each of the constituent elements needs to be sequentially fitted and assembled to a valve mounting hole of a valve housing, there are drawbacks in which it is difficult to precisely position each of the constituent elements, excessive assembling time is required, and the manufacturing cost increases.

In addition, the bypass valve applied to the conventional oil cooler has a drawback in which, when cooling of the transmission oil is not required, since a part of the low-temperature transmission oil cooled in the oil cooler flows into the bypass valve from the transmission and then flows back into the transmission, together with the bypassed transmission oil in a high-temperature state, rapid warming of the transmission oil is difficult.

BRIEF SUMMARY

Various aspects of the present invention are directed to providing an oil cooler for a vehicle having advantages of improving spatial utility of an engine compartment by having a bypass valve which is operated according to temperature of a working fluid.

According to various aspects of the present invention, an oil cooler for a vehicle may include a header tank partitioned by a diaphragm formed at an inside of a center in a length direction thereof, and adapted to take in a working fluid at a first side and to take out the working fluid at a second side with respect to the diaphragm, a connection tank disposed to be spaced apart from the header tank by a predetermined interval, a plurality of tubes mounted along a length direction at an interior surface of the header tank to connect with the connection tank such that the working fluid flows therethrough, and a bypass valve integrally mounted at an outside of the header tank and connected to the inside of the header tank so as to bypass or flow the working fluid flowing therein into the inflow tank by selectively opening/closing according to a temperature of the working fluid.

The header tank and the connection tank may be adapted to have the tubes therebetween, and may be fixed by a side plate which is mounted to connect insides of both ends of the header tank with insides of both ends of the connection tank in a state of being disposed apart from each other.

The working fluid may be transmission oil introduced from a transmission.

The working fluid may be configured such that when the bypass valve is opened, the working fluid flows into the first side of the header tank with respect to the diaphragm, flows into the connection tank through each tube, flows from the connection tank through each tube, and flows into the second side of the header tank with respect to the diaphragm.

The working fluid may flow in a U-turn flow direction to be discharged from the header tank via the connection tank and then flows into the header tank again, and may be cooled by passing through each of the tubes so as to be heat exchanged with outside air.

The bypass valve may include a valve housing integrally mounted at the outside of the header tank, and a controller mounted at an inside of the valve housing and adapted to flow the working fluid having flowed therein into the inflow tank or to bypass it by performing expansion or contraction according to the temperature of the inflowed working fluid.

The valve housing may include a first inflow hole formed at a first side thereof, which is an opposite side of the header tank, such that an inflow port is mounted thereto, a bypass hole formed at a second side thereof which is positioned apart from the first inflow hole such that a bypass port is mounted thereto, a second inflow hole formed to correspond with the first inflow hole at one surface which contacts the header tank and communicated with the first side of the inside of the header tank with respect to the diaphragm, and a discharge hole formed apart from the second inflow hole so as to be communicated with the second side of the inside of the header tank with respect to the diaphragm.

The controller may include a sliding member of which a first end is open and a mounting part is formed at a center of a second end, at least one first opening hole is formed on a first side corresponding to the first inflow hole and the bypass hole along the length direction, and at least one second opening hole is formed on a second side corresponding to the second inflow hole and the discharge hole along the length direction, and which is inserted to be slidable inside the valve housing, an end cap adapted to be mounted to a mounting hole which is formed at the valve housing such that the sliding member is inserted into the mounting hole, to close the mounting hole, and to form a fixing groove at the center thereof, a fixing rod adapted such that a first end thereof is fixed to the fixing groove, a deformable member inserted into the sliding member and adapted to forwardly or backwardly move on the fixing rod by extending or contracting according to a temperature of the working fluid that is changed such that the sliding member is selectively moved, and a first elastic member interposed between the valve housing and the sliding member and compressed or pulled so as to provide elastic force while the sliding member moves.

The first opening hole and the second opening hole may be separately formed at a first side and a second side in the length direction of the sliding member, respectively, and in the first and second opening holes positioned at the first side, a size of the first opening hole may be formed to be greater than a size of the second opening hole.

The sliding member may be configured such that when the deformable member is not deformed, the first opening hole may be positioned in the first inflow hole and the bypass hole, and of the second opening holes, the second opening hole positioned at the first side may be positioned below the second inflow hole, and the second opening hole positioned at the second side may be positioned in the discharge hole.

The sliding member may be configured such that when the deformable member is deformed, the fixing rod ascends and maintains the bypass hole and the discharge hole in an open state at a time of deformation of the deformable member, and the first and second opening holes positioned at the first side are positioned in the first and second inflow holes to open the first and second inflow holes.

The sliding member may be fixed to the deformable member through a fixing ring mounted between the mounting part and the deformable member below the deformable member inserted to the mounting part.

A seal ring that prevents the working fluid flowing into the valve housing from leaking to an outside of the valve housing may be mounted between the valve housing and the end cap.

The end cap may be fixed to the valve housing through a mounting ring that is fixedly mounted to an interior circumferential surface of mounting hole.

The mounting ring may be fixedly mounted through a ring groove formed along a periphery of the interior circumferential surface of the mounting hole.

The sliding member may include at least one relief hole that is formed at a position spaced apart from the mounting part at the second end in which the mounting part is formed.

A plurality of the relief holes may be formed at positions spaced apart from each other at a predetermined angle along a circumferential direction around the mounting part.

A pressure controller which is configured to selectively open and close the relief hole when a differential pressure occurs by the working fluid having flowed inside the valve housing may be provided between the sliding member and the deformable member.

The pressure controller may include an opening and closing member disposed inside the second end of the sliding member to correspond to the relief hole, and a second elastic member interposed between the opening and closing member and the deformable member inside the sliding member, and configured to apply elastic force to the opening and closing member.

The opening and closing member may be formed in a disk shape having a penetration hole formed at a center thereof to correspond to the mounting part.

The opening and closing member may be integrally formed with a protrusion that protrudes toward the second elastic member from an interior circumferential surface of the penetration hole.

The valve housing may form a mounting space where the first and second inflow holes, the bypass hole, and the discharge hole communicate therewith.

As mentioned above, in accordance with an oil cooler for a vehicle according to various embodiments of the present invention, by having a bypass valve which is operated according to temperature of working fluids, there is an effect of improving spatial utility of an engine compartment.

Furthermore, by controlling the flow stream of the working fluids to allow the working fluids to bypass or flow into the oil cooler, while rapidly expanding or contracting depending on the temperature of working fluids through a bypass valve provided integrally, the oil cooler having a simple structure, there is an effect of achieving convenient manufacturing and assembling, and reducing manufacturing cost through simplification of the constituent elements.

In addition, there are effects in which, during bypass of the working fluid, the required power of the hydraulic pump can be reduced through the increase of flow rate, and by assembling the internal constituent elements to the valve housing later, and since the internal components can be replaced after breakdown, the maintenance costs and reduced and the convenience of replacement work is improved.

Further, there are effects in which the flow rate can be increased by securing the bypass flow passage compared to the related art, by preventing the transmission oil cooled by the oil cooler from leaking to the transmission in advance.

Further, reliability of the flow stream control according to temperature of the transmission oil can be secured, and by reducing the friction loss inside the transmission through the rapid warming of the transmission oil, the overall fuel consumption efficiency of the vehicle is improved.

DETAILED DESCRIPTION

FIG. 1is a block diagram of a transmission oil cooling system to which an oil cooler for a vehicle according to various embodiments of the present invention is applied,FIG. 2is a front view of the oil cooler for a vehicle according to various embodiments of the present invention,FIG. 3is a cross-sectional view taken along line A-A ofFIG. 2, andFIG. 4is an enlarged view of part B ofFIG. 3.

The oil cooler100for the vehicle according to various embodiments of the present invention is configured to pass a working fluid therein or bypass the same depending on a temperature of the working fluid which flows therein. Therefore, the oil cooler cools the working fluid by exchanging heat with outdoor air introduced from the outside as an air-cooling type.

Here, the working fluid may be configured of transmission oil introduced from a transmission5.

That is, in the various embodiments, the oil cooler100is, as shown inFIG. 1, integrally configured with a bypass valve110. The oil cooler100is connected to the transmission5mounted on one side of an engine3through the bypass valve110.

The oil cooler100is disposed in front of a radiator7through which heat exchanges with the flowing outside air while traveling. The bypass valve110rapidly bypasses or flows into the oil cooler100depending on the temperature of the transmission oil introduced from the transmission5.

As shown inFIG. 2andFIG. 3, the oil cooler100includes a header tank101, a connection tank103, tubes (T), and the bypass valve110.

The inside of header tank101is partitioned by a diaphragm102which is formed at an inside of the center thereof in the length direction. The transmission oil flows into one side of the header tank101and is discharged to the other side of the header tank101with respect to the diaphragm102.

The connection tank103is disposed to be spaced apart from the header tank101by a predetermined interval.

In the various embodiments, a plurality of the tubes T are mounted along a length direction at the interior surface of the header tank101so as to connect with the connection tank103such that the transmission oil flows therethrough.

The header tank101and the connection tank103may be adapted to have the tubes T therebetween, and are fixed by side plates105which are mounted so as to connect the insides of both ends of the header tank101with the insides of both ends of the connection tank103in state of being disposed apart from each other.

The bypass valve110is integrally mounted to an outside of the header tank101and is connected to an inside of the header tank101. The bypass valve110is selectively opened or closed according to a temperature of the transmission oil, which flows from transmission5, so as to bypass the transmission oil or flow the transmission oil into the header tank101.

When the bypass valve110is opened, the transmission oil flows into one side of the header tank101with respect to the diaphragm102and flows into the connection tank103through each tube T. Thereafter, the transmission oil flows from the connection tank103through each tube T, and flows into the other side of the header tank101with respect to the diaphragm102.

That is, the transmission oil flows as a U-turn flow type to be discharged from the header tank101via the connection tank103and then flows into the header tank101again, and is cooled by passing through each of the tubes T so as to be heat exchanged with the outside air.

As shown inFIG. 4andFIG. 5, the bypass valve110includes a valve housing111and a controller120.

In the various embodiments, the valve housing111is integrally mounted at the outside of the header tank101.

The valve housing111may have a first inflow hole112formed at one side thereof, which is an opposite side of the header tank101such that an inflow port P1is mounted thereto, and a bypass hole114formed in the other side thereof which is positioned apart from the first inflow hole112such that a bypass port P2is mounted thereto.

Furthermore, the valve housing111may have a second inflow hole113formed to correspond with the first inflow hole112at one surface which contacts the header tank101and communicating with the one side of the inside of the header tank101with respect to the diaphragm102, and a discharge hole115formed apart from the second inflow hole113so as to communicate with the other side of the inside of the header tank101with respect to the diaphragm102.

The inflow port P1of the valve housing111is mounted to the first inflow hole112which is formed at an upper portion of the valve housing111in the drawing. The bypass port P2is mounted to the bypass hole114which is formed at a lower portion of the first inflow hole112so as to be connected to the transmission5.

A mounting space S may be formed at the valve housing111. The mounting space S communicates with the first and second inflow holes112and113, the bypass hole114, and the discharge hole115such that transmission oil flows into or is exhausted from the transmission5or the header tank101.

In the various embodiments, the first inflow hole112may be positioned on the same line as the second inflow hole113at respective sides of the upper portion of the valve housing111, and the bypass hole114may be positioned on the same line as the discharge hole115at respective sides of the lower portion of the valve housing111.

The controller120is mounted at the mounting space S of the valve housing111and is adapted to flow the transmission oil having flowed therein into the header tank101or bypass it by performing expansion or contraction according to the temperature of the inflowed transmission oil introduced from the transmission5.

The controller120controls the flow stream of the transmission oil by selectively communicating the first inflow hole112, which is formed to the inflow port P1, with the second inflow hole113or the bypass hole114by selectively closing the discharge hole115.

The controller120includes a sliding member121, an end cap127, a fixing rod135, a deformable member137, and a first elastic member141.

One end of the sliding member121is open, and a mounting part122protruding toward the inside upper part to form a hole is formed at the other end center.

At least one first opening hole123is formed on one side of the sliding member121corresponding to the first inflow hole112and the bypass hole114along the length direction.

Furthermore, the sliding member121is formed with at least one second opening hole125on the other side corresponding to the second inflow hole113and the discharge hole115along the length direction.

The sliding member121is inserted into the valve housing111so as to be mounted into the mounting space (S) in a slidable manner.

Such a sliding member121can be formed in a cylindrical shape in which one end facing upward is open and the other end except the mounting part122is closed in the drawing.

Here, the first opening hole123and the second opening hole125are formed at the top and bottom in the length direction of the sliding member121to be spaced apart from each other, and in the first and second opening holes123and125positioned at the top, the size of the first opening hole123can be formed to be greater than the size of the second opening hole125.

In the various embodiments, the end cap127is mounted to a mounting hole H which is formed in the valve housing111, and a fixing groove129is formed at the center thereof.

The end cap127is mounted to seal the mounting space S of the valve house111except the first and second inflow holes112and113, the bypass hole114, and the discharge hole115at the mounting hole H for preventing the transmission oil from leaking from the mounting hole H.

The end cap127can be fixed to the valve housing110through a mounting ring131fixedly mounted to the interior circumferential surface of the open other end of the valve housing111.

Moreover, the mounting ring131can be fixedly mounted through a ring groove118formed along the periphery of the interior circumferential surface of the open other end of the valve housing111.

That is, the other end of the end cap127is supported through the mounting ring131mounted in the ring groove118in a state in which the one end of the end cap127is inserted into the mounting hole H of the valve housing110, and thus the end cap127is fixedly mounted to the valve housing111.

Meanwhile, a seal ring133configured to prevent the transmission oil flowing into the valve housing110from leaking to the outside of the valve housing110can be mounted between the inflow of the valve housing110and the end cap127.

That is, the seal ring133seals between the exterior circumferential surface of the end cap127and the mounting hole H to prevent the transmission oil from leaking to the outside.

In the various embodiments, the fixing rod135is formed in a circular rod shape, and the other end thereof is fixed to the fixing groove129of the end cap127.

The deformable member137is inserted to the mounting part122of the sliding member121, and the bottom of the deformable member137is inserted to one end of the fixing rod135.

Expansion or contraction is performed thereinside through such a deformable member137depending on the temperature change of the transmission oil, and the position thereof is varied through occurrence of linear displacement with the ascent or descent of the fixing rod135to selectively move the sliding member121forward or backward.

The sliding member121can be fixed to the deformable member137through a fixing ring139that is mounted between the mounting part122and the deformable member137below the deformable member137inserted to the mounting part122.

In the various embodiments, the deformable member137can include a wax material of which contraction and expansion are performed thereinside depending on the temperature of a working fluid such as transmission oil.

The wax material is a material of which volume expands or contracts depending on the temperature, that is, its volume expands when temperature increases, and its volume contracts when the temperature decreases and it returns to its initial volume.

The deformable member137is formed by an assembly including the wax material thereinside, and when the volume deformation of the wax material occurs thereinside depending on the temperature, the deformable member137can move forward or backward on the fixing rod135, while an external shape thereof is not deformed.

Accordingly, when the transmission oil exceeding the predetermined temperature flows to the deformable member137through the inflow port P1, as the volume thereof expands, the deformable member137moves the sliding member121forward, while rising on the fixing rod135from the initial position mounted on the fixing rod135.

Conversely, as described above, when the transmission oil below the predetermined temperature flows in a state of expansion of volume, since the volume contracts, the deformable member137moves backward on the fixing rod135and returns the sliding member121to the initial position.

Furthermore, when the transmission oil below the predetermined temperature flows to the deformable member137in the initial state of being mounted to the fixing rod135, since the expansion or contraction does not occur, the position is not varied.

The first elastic member141is interposed between the sliding member121inside the valve housing111, and when ascending or descending depending on the expansion or contraction of the deformable member137, the first elastic member141is compressed or pulled to provide elastic force to the sliding member121.

The first elastic member141may be formed by a coil spring, one end of which is supported on the inner side of the closed one end of the valve housing111, and the other end of which is supported on the inner side of the other end of the sliding member121.

Furthermore, the valve housing111is formed with a support groove119to which the first elastic member141is fixed in a supported state on the inner side of the one end, and the one end of the first elastic member141is stably supported through the support groove119.

The operation of the bypass valve110configured as above will be described below referring to the accompanyingFIG. 6AandFIG. 6B.

FIG. 6AandFIG. 6Bare diagrams of a step-by-step operation state of the bypass valve that is used for the oil cooler for a vehicle according to various embodiments of the present invention.

As in S1ofFIG. 6A, when the transmission oil flowing in through the inflow port P1is below the predetermined temperature, since the deformable member137is not deformed, the sliding member121maintains the initial mounting state.

In this case, the first opening hole123of the sliding member121is located in the first inflow hole112and the bypass hole114, thereby opening the first inflow hole112and the bypass hole114.

In the second opening holes125, the second opening hole125located at the top maintains the state of closure of the second inflow hole113in the state of being located below the second inflow hole113, and the second opening hole125located at the bottom is located at the discharge hole115to keep the discharge hole115in an open state.

Accordingly, the transmission oil flowing into the first inflow hole112from the transmission5flows into the transmission5again through the bypass hole114, as the second inflow hole113maintains the closed state.

The bypass valve110is able to rapidly warm up the transmission5by allowing the transmission oil below the predetermined temperature having flowed from the transmission5to bypass to the transmission5again through the bypass hole114, without cooling through the header tank101when the transmission oil is below the predetermined temperature.

The transmission oil is saved in the other side of the inside of the header tank101with respect to the diaphragm102in a cooled state and flows in the valve housing111through the opened discharge hole115, but since the transmission oil does not flow into the header tank101through the closed second inflow hole113, only a very small amount of transmission oil flows through the second inflow hole113and flows into the transmission5, together with the transmission oil allowed to bypass through the bypass hole114.

That is, the very small amount of cooled transmission oil having flowed through the discharge hole115does not affect the temperature of the transmission oil allowed to bypass, and as the non-cooled transmission oil continuously bypasses and flows into the transmission5, the warming of the transmission5can be more rapidly performed.

Thus, with the oil cooler100according to various embodiments of the present invention, since the transmission5can be more rapidly warmed through the above-described operation of the bypass valve110, it is possible to improve the overall fuel efficiency of the vehicle by reducing the friction loss inside the transmission5.

In contrast, as in S2ofFIG. 6B, the sliding member121moves forward (ascends in the drawing) in the mounting space (S) of the valve housing111as the deformable member137expands and is deformed when a temperature of the transmission oil having flowed through the first inflow hole112is the same as or higher than the predetermined temperature.

The sliding member121is forwarded to the inside of the valve housing111such that the bypass hole114and the discharge hole115are maintained in the open state.

The first and second opening holes123and125located at the top are located in the first inflow hole112and the second inflow hole113, thereby the first and second inflow holes112and113are maintained in the open state.

At this time, the transmission oil which flows into the first inflow hole112through the inflow port P1and having a temperature that is the same as or higher than the predetermined temperature flows into the header tank101through the second inflow hole113. The transmission oil having flowed into the one side of the header tank101with respect to the diaphragm102flows into the connection tank103through each of the tubes T so as to be firstly cooled by heat exchanging with the outside air.

The firstly cooled transmission oil flows from the connection tank103into the other side of the header tank101with respect to the diaphragm102through each of the tubes T so as to be secondly cooled by heat exchanging with the outside air.

The transmission oil having flowed out from the header tank101flows from the header tank101into the valve housing111through the discharge hole115and then flows from the valve housing111into the transmission5through the bypass hole114.

Accordingly, the transmission oil cooled in the oil cooler100flows into the transmission5that is overheated due to the temperature rise of the transmission oil to cool the transmission5.

Meanwhile, when the sliding member121is forwarded by the deformable member137moving along the fixing rod135, the first elastic member141is in a state of being compressed between the valve housing110and the sliding member121.

In such a state, when the temperature of the transmission oil having flowed through the first inflow hole112falls below the predetermined temperature, the deformable member137moves the fixing rod135backwards, while contracting and again being deformed to the initial state from the expansion state.

At this time, the sliding member121more rapidly descends to the initial position by elastic force of the first elastic member141in the compressed state, as in S1ofFIG. 6Aas the initial mounting state, thereby closing the opened second inflow hole113.

The oil cooler100may be controlled with the flow stream of the transmission oil through the above-described operation of the bypass valve110according to the temperature of the inflow transmission oil introduced from the transmission5.

In the various embodiments, the sliding member121is formed with at least one relief hole143that is formed at a position spaced apart from the mounting part122on the other end formed with the mounting part122.

Such relief holes143can be formed at positions spaced apart from each other at a predetermined angle along the circumferential direction around the mounting part122, and in the various embodiments, four relief holes143are formed at positions spaced apart from each other around the mounting part122at an angle of 90°.

In the various embodiments, the four relief holes143formed at the positions spaced from each other along the circumferential direction around the mounting part122at the angle of 90° are described as exemplary embodiments, but the present invention is not limited thereto, and the size, the number, and the positions of the relief holes143can be modified and applied.

In the various embodiments, a pressure controller150can be provided between the sliding member121and the deformable member137. The pressure controller150selectively opens and closes the relief hole143to control the internal pressure of the valve housing111, when differential pressure occurs by the cooled transmission oil having flowed from the oil cooler9inside the valve housing111.

The pressure controller150is configured to include an opening and closing member151that is disposed inside the other end of the sliding member121so to be able to ascend and descend to correspond to the relief hole143, and a second elastic member155that is disposed between the opening and closing member151and the deformable member137inside the sliding member121and that supplies elastic force to the opening and closing member151.

The opening and closing member151is formed in a disk shape with a penetration hole152at the center to correspond to the mounting part122, and can be mounted to the inside of the other end of the sliding member121in the state of being inserted into the mounting part122through the penetration hole152.

Furthermore, the opening and closing member151can be integrally formed with a protrusion153that protrudes toward the second elastic member155from the interior circumferential surface of the penetration hole152.

Such the protrusion153guides the opening and closing member151so as to stably ascend and descend along the mounting part122, when the differential pressure occurs depending on the flow rate of the transmission oil having flowed from the oil cooler9in the valve housing110or the generated differential pressure is released and the opening and closing member151ascends or descends.

The second elastic member155can be formed by a coil spring, one end of which is supported by the deformable member137, and the other end of which is supported by the opening and closing member151.

Hereinafter, the operation of the pressure controller150as configured above will be described referring toFIG. 7AandFIG. 7B.

FIG. 7AandFIG. 7Bare diagrams of a step-by-step operation state of the pressure controller that is applied to the valve for a vehicle according to various embodiments of the present invention.

Referring toFIG. 7AandFIG. 7B, the pressure controller150is selectively operated in a state in which the bypass hole114and the discharge hole115are open, as the sliding member121moves forward (ascends in the drawing) by the expansion deformation of the deformable member137.

When an amount of the cooled transmission oil having flowed from header tank101into the valve housing111via the discharge hole115is low, the pressure difference is not generated between the upper part and the lower part with respect to the bottom of the sliding member121in the valve housing111.

Accordingly, as in S10ofFIG. 7A, the pressure controller150maintains the initial mounting state in which the relief hole143is closed.

When an amount of the cooled transmission oil having flowed into the valve housing111through the discharge hole115is increased, the pressure difference is generated between upper part and lower part with respect to the bottom of the sliding member121in the valve housing111.

As in S20ofFIG. 7B, the opening and closing member151ascends by the pressure of the transmission oil due to the generated differential pressure to open the relief holes143.

Then, a part of the cooled transmission oil having flowed through the discharge hole115flows into the sliding member121through the open relief hole143, thereby eliminating the pressure difference inside the valve housing111that is located inside the sliding member121and below the sliding member121.

Furthermore, when the differential pressure inside the valve housing111is eliminated, the opening and closing member151of the pressure controller150is rapidly lowered by elastic force of the second elastic member155that is compressed during ascent of the opening and closing member151and returned to the initial mounting state, thereby again closing the relief holes143as in S10ofFIG. 7A.

That is, through the above-described operation, the bypass valve110may eliminate the pressure difference caused by the difference in flow rate of the transmission oil flowing into the valve housing111from the transmission5and the header tank101, by the operation of the relief hole143and the pressure controller150.

Furthermore, if the valve housing111eliminates the pressure difference caused by the difference thereinside, it may be possible to improve the overall pressure resistance and durability of the bypass valve110and to improve reliability and responsiveness of the valve operation.

As mentioned above, in accordance with the oil cooler100for a vehicle according to various embodiments of the present invention, by having a bypass valve110which is operated according to the temperature of the transmission oil, there is an effect of improving spatial utility of an engine compartment.

Furthermore, by controlling the flow stream of the working fluids to allow the working fluids to bypass or flow into the oil cooler100, while rapidly expanding or contracting depending on the temperature of transmission oil through a bypass valve110provided integrally, and the oil cooler100in a simple structure, there is an effect of achieving convenient manufacturing and assembling, and reducing manufacturing cost through simplification of the constituent elements.

In addition, there are effects in which, during bypass of the transmission oil, the required power of a hydraulic pump can be reduced through the increase of flow rate, by assembling the internal constituent elements to the valve housing111provided integrally with the header tank101later, and since the internal components can be replaced after breakdown, the maintenance costs are reduced and the convenience of replacement work is improved.

Further, there are effects in which the flow rate can be increased by securing the bypass flow passage compared to the related art, by preventing the transmission oil cooled by the oil cooler100from leaking to the transmission in advance via the bypass valve110.

Also, reliability of the flow stream control according to temperature of the transmission oil can be secured, and by reducing the friction loss inside the transmission5through the rapid warming of the transmission oil, the overall fuel consumption efficiency of the vehicle is improved.

Although the case in which the working fluid is configured of transmission oil introduced from a transmission5has been described by way of example in describing the oil cooler100for a vehicle according to various embodiments of the present invention, the present invention is not limited thereto. That is, all of working fluids that need to be warmed or cooled through heat exchange may be used as the working fluids.