A vacuum pump for generating a negative pressure includes a pump housing having a pump chamber with a rotor and a motor for driving the rotor with a drive shaft rotatable about a longitudinal axis, a first and a second inlet line. The second inlet line leads through the pump housing into the pump chamber. A first outlet line leads from the pump chamber through the pump housing. The pump has a first outlet valve and a second outlet line connected to the pump housing. A connecting part is attached to a connecting surface running circumferentially to the longitudinal axis, and the outlet valve with the second outlet line is formed in the connecting part. The connecting part further has the first inlet line, with a first connecting opening formed in the connecting part housing, via which the first inlet line is connected to the second inlet line.