Is there any mention on the minimum or maximum number of sleeping hours for humans in Vedas or puranas?
You should wake up before sunrise, and go to sleep after sunset. Here is what this chapter of the Manu Smriti says:
If the sun should rise or set while he is sleeping, be it (that he offended) intentionally or unintentionally, he shall fast during the (next) day, muttering (the Savitri). For he who lies (sleeping), while the sun sets or rises, and does not perform (that) penance, is tainted by great guilt.
And here is what this chapter of the Gauatama Dharma Sutras says:
Let him who was asleep when the sun rose remain standing during the day, continent and fasting, and him who was asleep when the sun set (remain in the same position) during the night, reciting the Gâyatrî.