A panel system, wherein the panel system comprises: a lower guide and an upper guide which are essentially parallel; at least one panel, which is movable and located between the lower guide and the upper guide and connected to the lower guide and the upper guide for moving the panel on the lower guide; a hinge element which is fixed to the panel, located inside the upper guide and allows the panel to be opened by turning the panel around a rotation axis; at least two locking housings which are in the upper guide and located successively in a longitudinal direction of the upper guide, each of the locking housings comprising two opposite locking recesses, the shapes of which together define a circle with a radius R3, and between which remains a passage having a width P2, the passage being parallel with the longitudinal direction of the upper guide and through which the hinge element can travel from one locking housing to another, wherein the distance between midpoints of the locking housings in the longitudinal direction of the upper guide is a distance P1, which is configured to be smaller than two times the radius R3; characterised in that the hinge element comprises two locking cams extending in opposite directions, the locking cams turning inside one of the locking housings when the panel is opened, rotating with the hinge element around the rotation axis and being configured to extend parallel with the longitudinal direction of the upper guide when the panel is parallel with the longitudinal direction of the upper guide, the locking cams comprising end surfaces, the shapes of the end surfaces defining a circle with a radius R1 that is smaller than the radius R3 by a clearance; that the width P2 is smaller than two times the radius R1; that the hinge element comprises a guiding edge remaining between the two locking cams, the guiding edge rotating with the hinge element around the rotation axis and the shape of the guiding edge defining a circle with a radius R2 in such a way that the radius R2 is smaller than the radius R1, wherein the radius R2 and the radius R1 combined is less than the distance P1; and that the hinge element further comprises a tapered section which is located between the two locking cams, on the opposite side of the rotation axis with respect to the guiding edge, the shape of the tapered section extending parallel with the longitudinal direction of the upper guide when the panel is parallel with the longitudinal direction of the upper guide, wherein the perpendicular distance between the guiding edge and the tapered section corresponds at most to the width P2. a lower guide and an upper guide which are essentially parallel; at least one panel, which is movable and located between the lower guide and the upper guide and connected to the lower guide and the upper guide for moving the panel on the lower guide; a hinge element which is fixed to the panel, located inside the upper guide and allows the panel to be opened by turning the panel around a rotation axis; at least two locking housings which are in the upper guide and located successively in a longitudinal direction of the upper guide, each of the locking housings comprising two opposite locking recesses, the shapes of which together define a circle with a radius R3, and between which remains a passage having a width P2, the passage being parallel with the longitudinal direction of the upper guide and through which the hinge element can travel from one locking housing to another, wherein the distance between midpoints of the locking housings in the longitudinal direction of the upper guide is a distance P1, which is configured to be smaller than two times the radius R3; characterised in that the hinge element comprises two locking cams extending in opposite directions, the locking cams turning inside one of the locking housings when the panel is opened, rotating with the hinge element around the rotation axis and being configured to extend parallel with the longitudinal direction of the upper guide when the panel is parallel with the longitudinal direction of the upper guide, the locking cams comprising end surfaces, the shapes of the end surfaces defining a circle with a radius R1 that is smaller than the radius R3 by a clearance; that the width P2 is smaller than two times the radius R1; that the hinge element comprises a guiding edge remaining between the two locking cams, the guiding edge rotating with the hinge element around the rotation axis and the shape of the guiding edge defining a circle with a radius R2 in such a way that the radius R2 is smaller than the radius R1, wherein the radius R2 and the radius R1 combined is less than the distance P1; and that the hinge element further comprises a tapered section which is located between the two locking cams, on the opposite side of the rotation axis with respect to the guiding edge, the shape of the tapered section extending parallel with the longitudinal direction of the upper guide when the panel is parallel with the longitudinal direction of the upper guide, wherein the perpendicular distance between the guiding edge and the tapered section corresponds at most to the width P2.