machine part in drink from restaurant

I am sorry to hear about this.  If the object in the drink caused you harm or damage, then you might have grounds for a lawsuit.  However, if it did not cause you any harm or damage and only "could have", you likely will not be successful with a lawsuit.  A lawsuit requires both a "harm" and "damages" and without those things, you will likely not be successful.  However, you might consider contacting the company and reporting this and they may offer you a small settlement or you can consult a local attorney.  Best of luck. NOTE:  This response is general in nature and should not be considered legal advice.  No attorney-client relationship exists or is formed by this response.