Partners have equity in the business too or they can't be partners, when someone joins as a partner they bring something to the mix, expertise valued at some amount, cash, equipment, something.

For a company taxed as a sole proprietor (schedule C) or partnership (form 1065), I recommend you have the following for owner/partner equity accounts  (one set for each partner if a partnership)

[name] Equity (do not post to this account it is a summing account)
>> Equity
>> Equity Drawing - you record value you take from the business here
>> Equity Investment - record value you put into the business here