A switch for a medium voltage or high voltage switchgear, the switch comprising:
- a first fixed contact;
- a second fixed contact;
- a moveable contact including a first end, a second end, and a pair of conductive rings disposed around and moveable with each the first end and the second end, the moveable contact including an inner diameter;
- a fixed earth contact;
- at least one flexible link, the at least one flexible link at least partially disposed within a link guide, the link guide including an outer diameter;
- and
- a contact drive;
- wherein, in an on state of the switch the moveable contact is in a position that connects the first fixed contact to the second fixed contact;
- wherein, in an off state of the switch the moveable contact is in a position where the first fixed contact is not connected to the second fixed contact;
- wherein, in an earthing state of the switch, the moveable contact is configured to be in a position that connects the second fixed contact to the fixed earth contact,
- wherein, the at least one flexible link is directly connected to the second end of the moveable contact;
- wherein the inner diameter of the moveable contact is larger than the outer diameter of the link guide such that the moveable contact is moveable along the link guide;
- wherein, the at least one flexible link engages with the contact drive, and wherein the contact drive is configured to pull the moveable contact via the at least one flexible link and the contact drive is configured to push the moveable contact via the at least one flexible link;
- wherein the contact drive comprises at least one chain wheel configured to engage with the at least one flexible link, and wherein rotation of a chain wheel of the at least one chain wheel in a first direction is configured to pull the at least one flexible link, and wherein rotation of the chain wheel in a direction counter to the first direction is configured to push the at least one flexible link;
- wherein the at least one flexible link comprises at least one chain, wherein the at least one chain comprises a push chain, wherein the push chain, when extended in a longitudinal axis, is configured to enable the chain to bend out of the axis in a first direction perpendicular to the axis and is configured to resist the chain being bent out of the axis in a second direction opposite to the first direction;
- wherein, activation of the contact drive in a first mode is configured to move the moveable contact to a position such that the switch is in the on state, wherein a first part of the chain is at least partially wrapped around the chain wheel;
- wherein, activation of the contact drive in a second mode is configured to move the moveable contact to a position such that the switch is in the off state, wherein a second part of the chain is at least partially wrapped around the chain wheel;
- wherein activation of the contact drive in a third mode is configured to move the moveable contact to a position such that the switch is in the earthing state, wherein a third part of the chain is at least partially wrapped around the chain wheel;
- wherein the switch is configured to transition between the second mode and the third mode without entering the first mode;
- wherein at least one of the first end and the second end, including the corresponding conductive rings, are maintained within the second fixed contact in each of the first mode, the second mode, and the third mode;
- and
- wherein the pair of conductive rings are configured to align the moveable contact with and remove axial misalignment between the moveable contact and at least one of the first fixed contact, the second fixed contact, and the fixed earth contact.