Internally clamping rectangular seal

An internally clamping seal for sealing a shaft with respect to a housing, wherein the seal can be inserted into a groove disposed circumferentially in a shaft bore of the housing, the seal comprising:

• a seal ring including a first ring-end section and a second ring end section, the first and second ring-end sections forming a joint interrupting the seal ring along a circumferential direction, the seal ring including an outer surface facing radially outwards, an inner clamping surface facing radially inwards, and opposing flank surfaces facing in opposite axial directions;
• wherein the first ring-end section includes two contact ramps oriented obliquely with respect to both the circumferential direction and the radial direction of the seal ring and spaced circumferentially from each other, and the first ring-end section includes a cover forming a continuous extension of the outer surface of the seal ring, the cover extending circumferentially past both of the two contact ramps;
• wherein two contact sections are disposed on the second ring-end section opposite to the two contact ramps;
• wherein both of the contact ramps are inclined in the same circumferential direction such that, when a radius of the seal ring is reduced by prestressing the seal ring, the second ring-end section is deflected inwards such that the ring-end sections slide radially on top of each other and form a flat spiral;
• and
• wherein the second ring-end section includes a centering cam projecting radially outward from the outer surface of the seal ring, the centering cam including an inclined surface facing the first ring-end section and configured such that when the radius of the seal ring is reduced by prestressing the seal ring a free end of the first ring-end section engages the inclined surface.