High voltage disconnect switch employing pre-contact pieces

A high voltage disconnect switch, comprising:

• a countercontact piece having switch countercontacts and being arranged for connection to a source of high voltage;
• resilient pre-contact pieces insulatingly connected to said countercontact piece and including switch contacts disposed for contacting said switch countercontacts;
• and
• movable primary contact pieces arranged to be movable from a first position of separation from said pre-contact pieces and said countercontact piece to a second position in which said primary contact pieces are in contact with said pre-contact pieces but not with said countercontact piece and to a third position in which said primary contact pieces are in contact with both said pre-contact pieces and said countercontact piece;
• wherein said pieces are configured and arranged relative to one another so that during the closing of said switch said countercontacts contact said contacts after said primary contact pieces are moved to the second position and before said primary contact pieces are moved to the third position, and during the opening of said switch said countercontacts separate from said contacts after said primary contact pieces are moved to the second position and before said primary contact pieces are moved to the first position.