Tension roller assembly configured for tensioning a belt (115,117) of a belt drive, the tension roller assembly comprising: - a tension roller, - a pivotable support arm having a support pivot at a pivot end thereof, wherein the tension roller is connected in a rotatable manner to an opposite, roller end of the support arm, the support arm comprising a tension arm connection point having a rod guide, - a tension arm connected at a first end thereof to the tension arm connection point of the support arm, wherein the tension arm comprises a compression spring configured to press the tension roller with force against the belt, wherein the tension arm comprises a first spring stop and a second spring stop mounted on the rod, wherein the spring extends between the first spring stop and the second spring stop and is maintained under compression, - a mounting plate, characterized by - an overcenter assembly connected to a second end of the tension arm, the second end being opposite to the first end, wherein the overcenter assembly connects the tension arm to the mounting plate, the overcenter assembly being configured to make a pivoting movement over a pivot trajectory between: a) an engaged position which is associated with an engaged state of the tension roller assembly, and b) a disengaged position which is associated with a disengaged state of the tension roller assembly, wherein the overcenter assembly further has a center position which is located between the engaged position and the disengaged position, wherein the tension arm comprises a rod which extends from the overcenter assembly to the support arm and through the rod guide, wherein the rod guide allows the rod to slide relative to the support arm, wherein the tension arm comprises an end stop which is mounted to an end of the rod which protrudes from the rod guide, wherein the support arm comprises a stop surface on the side of the end stop, the stop surface being configured to engage the end stop, wherein the end stop and the stop surface keep the spring under compression and prevent the spring from reaching its full length during a movement of the overcenter assembly from the center position to the disengaged position, wherein the trajectory of the overcenter assembly between the center position and the disengaged position is divided in: a) a tensioned section in which the end stop does not engage the stop surface and the spring exerts a force on the overcenter assembly, and b) a free-moving section in which the end stop engages the stop surface and the spring does not exert any force on the overcenter assembly. - a tension roller, - a pivotable support arm having a support pivot at a pivot end thereof, wherein the tension roller is connected in a rotatable manner to an opposite, roller end of the support arm, the support arm comprising a tension arm connection point having a rod guide, - a tension arm connected at a first end thereof to the tension arm connection point of the support arm, wherein the tension arm comprises a compression spring configured to press the tension roller with force against the belt, wherein the tension arm comprises a first spring stop and a second spring stop mounted on the rod, wherein the spring extends between the first spring stop and the second spring stop and is maintained under compression, - a mounting plate, characterized by - an overcenter assembly connected to a second end of the tension arm, the second end being opposite to the first end, wherein the overcenter assembly connects the tension arm to the mounting plate, the overcenter assembly being configured to make a pivoting movement over a pivot trajectory between: a) an engaged position which is associated with an engaged state of the tension roller assembly, and b) a disengaged position which is associated with a disengaged state of the tension roller assembly, a) an engaged position which is associated with an engaged state of the tension roller assembly, and b) a disengaged position which is associated with a disengaged state of the tension roller assembly, a) a tensioned section in which the end stop does not engage the stop surface and the spring exerts a force on the overcenter assembly, and b) a free-moving section in which the end stop engages the stop surface and the spring does not exert any force on the overcenter assembly.