You could use EEM to do that. Have a look here: https://community.cisco.com/t5/network-management/save-config-to-tftp-with-eem/td-p/1180756
Thanks for your replay,actually I did checked the mentioned post , its not working cause I've XR ios , in addition to that I want to do the copy operation in a scheduled time
Sorry, I made an assumption (not good) that IOS XR has EEM as well. So it's TCL only.