Is it legal if a husband wins a legal settlement and keeps it locked away from the wife in a separate account?

Without knowing more in the way of facts, generally, income or property received during a marriage is considered "marital property".  And in the event of a divorce, parties can seek an equitable division of all marital property and assets.   It is not uncommon for parties to retain separate bank accounts.  If it is your desire to pursue a portion of the proceeds your husband received, you should consult an attorney and provide the missing details.