Oil cooler for transmission

Abstract

Disclosed herein is a transmission oil cooler. The cooler includes heat exchange tubes stacked one on top of another. Each heat exchange tube comprises an upper plate and a lower plate coupled to each other. Recesses are formed in each of facing surfaces of the upper and lower plates. The recesses of the upper plate cross over the recesses of the lower plate. Ridges and valleys are alternately formed on the upper and lower plates. Each heat exchange tubes has, on opposite ends thereof, an inlet port and an outlet port. An upper flange is provided around each of the inlet port and the outlet port. A lower flange is provided around each of the inlet port and the outlet port. The upper flange and the lower flanges of the adjacent heat exchange tubes are coupled to each other by fitting.

1 . A transmission oil cooler, comprising a plurality of heat exchange tubes stacked one on top of another,
 wherein a coolant path is formed between the heat exchange tubes so that a coolant passes along the coolant path, and each of the heat exchange tubes comprises an upper plate and a lower plate coupled to each other by bonding perimeters thereof to each other, the heat exchange tube having an oil path along which oil passes,   a plurality of recesses is formed in each of facing surfaces of the upper and lower plates, the recesses of the upper plate crossing over the recesses of the lower plate, thus forming a cross structure of the oil path,   a plurality of ridges and a plurality of valleys are continuously and alternately formed on each of an upper surface of the upper plate and a lower surface of the lower plate, the ridges and valleys extending parallel to each other in a diagonal direction,   each of the heat exchange tubes has, on opposite ends thereof, an inlet port through which the oil is drawn into the heat exchange tube, and an outlet port through which the oil is discharged out of the heat exchange tube, and the oil paths of the heat exchange tubes communicate with each other through the inlet ports and the outlet ports,   the upper plate comprises an upper flange provided around each of the inlet port and the outlet port, the upper flange protruding upwards from the upper surface of the upper plate, and the lower plate comprises a lower flange provided around each of the inlet port and the outlet port, the lower flange protruding downwards from the lower surface of the lower plate, and   protrusions are discontinuously or continuously formed along the ridges on the upper and lower plates.   
     
     
         2 . The transmission oil cooler as set forth in  claim 1 , wherein the upper flange and the lower flanges of the adjacent heat exchange tubes are coupled to each other by fitting. 
     
     
         3 . The transmission oil cooler as set forth in  claim 2 , wherein at least one of the upper and lower flanges is tapered inwards on an end thereof. 
     
     
         4 . The transmission oil cooler as set forth in  claim 1 , wherein the protrusions comprise a plurality of upper pin-shaped protrusions provided on the corresponding ridges of the upper plates, and a plurality of lower pin-shaped protrusions provided on the corresponding ridges of the lower plates, and the upper pin-shaped protrusions and the lower pin-shaped protrusions of the adjacent heat exchange tubes are in contact with each other. 
     
     
         5 . The transmission oil cooler as set forth in  claim 4 , wherein the upper pin-shaped protrusions are arranged on an upper surface of each of the corresponding ridges of the upper plate at positions spaced apart from each other at regular intervals, and the lower pin-shaped protrusions are arranged on a lower surface of each of the corresponding ridges of the lower plate at positions spaced apart from each other at regular intervals. 
     
     
         6 . The transmission oil cooler as set forth in  claim 4 , wherein the upper pin-shaped protrusions and the lower pin-shaped protrusions are disposed at positions at which the recesses of the upper plate cross over the recesses of the lower plate. 
     
     
         7 . The transmission oil cooler as set forth in  claim 4 , wherein each of the upper pin-shaped protrusions has a contact surface on an upper surface thereof, and each of the lower pin-shaped protrusions has a contact surface on a lower surface thereof. 
     
     
         8 . The transmission oil cooler as set forth in  claim 4 , wherein a cross-section of each of the upper and lower pin-shaped protrusions has one shape selected from a trapezoidal shape, a round shape and a rectangular shape. 
     
     
         9 . The transmission oil cooler as set forth in  claim 1 , wherein the protrusions comprise a plurality of bar-shaped protrusions provided between the ridges of the upper and lower plates, each of the bar-shaped protrusions extending in a longitudinal direction of the ridges, wherein a height of each of the bar-shaped protrusions is greater than a height of the ridges, and the bar-shaped protrusions of the adjacent heat exchange tubes are in contact with each other. 
     
     
         10 . The transmission oil cooler as set forth in  claim 9 , wherein the recesses formed in the facing surfaces of the upper and lower plates comprise a plurality of first recesses formed at sides opposite to the respective ridges, and a plurality of second recesses formed at sides opposite to the respective bar-shaped protrusions. 
     
     
         11 . The transmission oil cooler as set forth in  claim 9 , wherein each of the bar-shaped protrusions of the upper plate has a contact surface on an upper surface thereof, and each of the bar-shaped protrusions of the lower plate has a contact surface on a lower surface thereof. 
     
     
         12 . The transmission oil cooler as set forth in  claim 9 , wherein a cross-section of each of the bar-shaped protrusions of the upper and lower plates has one shape selected from a trapezoidal shape, a round shape and a rectangular shape. 
     
     
         13 . The transmission oil cooler as set forth in  claim 1 , wherein a positioning depression and a positioning protrusion are respectively formed at predetermined positions corresponding to each other on portions at which the upper plate is in contact with the lower plate.