If you've configured a regular Time Machine backup onto your Time Capsule, mounting (or unmounting) the sparsebundle is not needed. It's already mounted or you wouldn't be able to backup your data regularly.
To mount the remote Time Machine sparsebundle and get the path to it simply enter:
tmutil latestbackup > /dev/null 2>&1 if you don't want any output)
The command triggers the mounting of the sparsebundle and the output is the path to your last backup.
mount will show you the mount points of the Time Capsule and your sparsebundle.
Your result will be something like (example listing):
/dev/disk1s2 on / (hfs, local, journaled)
devfs on /dev (devfs, local, nobrowse)
map -hosts on /net (autofs, nosuid, automounted, nobrowse)
map auto_home on /home (autofs, automounted, nobrowse)
//%user%@%IP% on /Volumes/%TimeCapsule% (afpfs, nobrowse)
/dev/disk2s2 on /Volumes/%Time Machine-Backups% (hfs, local, nodev, nosuid, journaled, nobrowse)
The second last line is the Time Capsule share, the last line (disk2s2) the mounted sparsebundle image. The mounted share/sparsebundle aren't visible in the Finder because they are flagged as nobrowse.
To access your backup you can simply enter something like:
cd "/Volumes/%Time Machine Backups%/Backups.backupdb/%LocalHostName%/
(All terms framed by percent signs depend on your environment and you have to replace them by proper names/addresses - get them by diving into the folders with