dimming leds with tip122 and voltage variable

Im trying to dimming two LEDs in parallel with a power supply of 3-48V variable and 1.4A constants with a TIP122. If I use a 3.7V battery I have no problems, but the supply give me 48V and tip begins heating extremely, but leds only needs 3V. This is like transistor demands all power capacity. Im using a 2k2 resistor on the base. any idea? thanks


[Draw it out on a sheet of paper, take a picture of that and include it as an attachment.]