Peristaltic pump cassette arrangement using multiple tubes and a pressure plate

A peristaltic pump comprising:

• a motor with a motor shaft;
• and
• a cassette with a rotor that is connected to the motor shaft, wherein the rotor comprises a plurality of rollers, wherein at least one tube which surrounds the rotor partially is located between the plurality of rollers and a pressure plate which is mounted to one of two side walls, wherein a spring is located between the pressure plate and a cover for applying a force to the pressure plate against the at least one tube, wherein the cover comprises a locking lever configured to engage with outer hooks arranged on top of each side wall by rotating the locking lever and wherein the pressure plate comprises guiding ribs located on the inner surface of the pressure plate facing the at least one tube and the guiding ribs are located on both sides of the at least one tube, characterised in that the at least one tube is connected with a first end to a first vertical tube connector of a first external connector on one side of the rotor and with a second end to a second vertical tube connector of a second external connector on the opposite side of the rotor, wherein the first and second vertical tube connector of the external connectors are connected to a connecting tube of a bridge providing at least one outlet, wherein the bridge comprises on its outer ends protrusions as connecting elements which engage into recesses of a side wall plate of the side wall, wherein the bridge is configured to engage into the side walls on both sides of the rotor and the locking lever is configured to rotate in a closed position only when the protrusions of the bridge engage with the recesses of the side walls.