Screen device

A screen device, comprising

• a screen roller;
• a screen which can be rolled and unrolled on the screen roller, wherein the screen comprises:
• a first end fitted to the screen roller,
• a second end disposed opposite to the first end,
• a first lateral side, and
• a second lateral side disposed opposite to the first lateral side;
• an end lath, which is fitted to the second end of the screen roller;
• a tensioning system to tension the screen when the screen is rolled and unrolled on the screen roller, comprising on each of the first and the second lateral sides of the screen:
• a band wheel, which is arranged next to the screen roller;
• a tensioning cord fitted on the band wheel, which can be rolled and unrolled on the band wheel;
• a reversing wheel connected to the tensioning cord, via which the tensioning cord is turned;
• and
• a first spring sub-system disposed on the first lateral side of the screen and a second spring sub-system disposed on the second lateral side of the screen, wherein each of the spring sub-systems comprises:
• at least one spring for keeping each of the respective tensioning cords under tension,
• a first pivot arm, which is articulately fastened to a first fixed pivot pin, wherein the first fixed pivot pin is fixedly arranged in the screen device and is articulately fastened to a displaceable pivot pin arranged displaceably in the screen device, and
• a second pivot arm, which is articulately fastened to the displaceable pivot pin and which is articulately fastened to a second fixed pivot pin, wherein the second fixed pivot pin is fixedly arranged in the screen device,
• wherein each of the tensioning cords is fastened to the end lath,
• wherein the first spring sub-system comprises a first plurality of fixtures for adjusting a spring force of the at least one spring,
• wherein the first pivot arm comprises a first part-arm and a second part-arm, the first part-arm and the second part-arm arranged resiliently with respect to each other such that the spring force of the at least one spring drives the part-arms apart, and
• wherein around each of the displaceable pivot pins is fitted a guide wheel, via which each of the respective tensioning cords is turned.