A switching device comprising: - an outer casing defining an internal volume of said switching device, wherein the outer casing comprises a rear portion, a front portion and a cover portion, wherein the rear portion comprises opposite first and second sides (211, 212) and opposite first lateral sides and the front portion comprises opposite third and fourth sides (221, 222) and opposite second lateral sides, wherein the rear portion and the front portion are mutually coupled at the respective second and third sides (212, 221), which define a first internal volume portion; - one or more electric poles, each electric pole comprising one or more mobile contacts and one or more fixed contacts adapted to be coupled or uncoupled during a switching operation of said switching device; - a contact shaft accommodated in the first internal volume portion and adapted to rotate about a rotation axis during a switching operation of said switching device, said contact shaft having a shaped body comprising one or more contact seats adapted to accommodate at least partially said mobile contacts, so that said mobile contacts rotate with said contact shaft about said rotation axis during a switching operation of said switching device; - a control mechanism for operating said contact shaft, said control mechanism comprising a supporting frame (51, 510) fixed to said outer casing to provide support to movable members of said control mechanism and one or more connecting rods to provide a force to move said contact shaft during a switching operation of said switching device; wherein it comprises one or more coupling elements to support said contact shaft and maintain said contact shaft in a suspended position within said internal volume and to provide a mechanical connection between said control mechanism and said contact shaft, said coupling elements comprising: - a first coupling point, at which said coupling elements are fixed to said contact shaft, so that said coupling elements provide support to said contact shaft and maintain said contact shaft in relative position with respect to said outer casing; - a second coupling point, at which said coupling elements are hinged with corresponding supporting frame portions of said supporting frame, so that said coupling elements provide a centre of rotation for said contact shaft about said rotation axis, the coupling elements fixing the position of the rotation axis of the contact shaft within the first internal volume portion at the second coupling points that are spaced apart from the first coupling points; - a third coupling point, at which said coupling elements are hinged with corresponding connecting rods of said control mechanism, so that said connecting rods exert a force on said coupling elements to rotate said coupling elements and said contact shaft about said rotation axis, during a switching operation of said switching device; characterized in that the coupling elements are at least partially accommodated in corresponding coupling recesses of said contact shaft. - an outer casing defining an internal volume of said switching device, wherein the outer casing comprises a rear portion, a front portion and a cover portion, wherein the rear portion comprises opposite first and second sides (211, 212) and opposite first lateral sides and the front portion comprises opposite third and fourth sides (221, 222) and opposite second lateral sides, wherein the rear portion and the front portion are mutually coupled at the respective second and third sides (212, 221), which define a first internal volume portion; - one or more electric poles, each electric pole comprising one or more mobile contacts and one or more fixed contacts adapted to be coupled or uncoupled during a switching operation of said switching device; - a contact shaft accommodated in the first internal volume portion and adapted to rotate about a rotation axis during a switching operation of said switching device, said contact shaft having a shaped body comprising one or more contact seats adapted to accommodate at least partially said mobile contacts, so that said mobile contacts rotate with said contact shaft about said rotation axis during a switching operation of said switching device; - a control mechanism for operating said contact shaft, said control mechanism comprising a supporting frame (51, 510) fixed to said outer casing to provide support to movable members of said control mechanism and one or more connecting rods to provide a force to move said contact shaft during a switching operation of said switching device; - a first coupling point, at which said coupling elements are fixed to said contact shaft, so that said coupling elements provide support to said contact shaft and maintain said contact shaft in relative position with respect to said outer casing; - a second coupling point, at which said coupling elements are hinged with corresponding supporting frame portions of said supporting frame, so that said coupling elements provide a centre of rotation for said contact shaft about said rotation axis, the coupling elements fixing the position of the rotation axis of the contact shaft within the first internal volume portion at the second coupling points that are spaced apart from the first coupling points; - a third coupling point, at which said coupling elements are hinged with corresponding connecting rods of said control mechanism, so that said connecting rods exert a force on said coupling elements to rotate said coupling elements and said contact shaft about said rotation axis, during a switching operation of said switching device;