Lower guide unit of electrical discharge machine

A lower guide unit configured to guide a vertically lower portion of a tool electrode in an electrical discharge machine for electrical discharge machining, comprising:

• a housing comprising a fitting hole having a tapered surface,
• an electrode guide comprising a tapered portion tapering upward, and
• a pull-up mechanism comprising a guide support, a plurality of links, and a power cylinder,
• wherein the guide support comprises at least one biasing member and a displacement member,
• the biasing member is arranged to bias the displacement member in a vertical direction,
• the displacement member is configured to be displaced in the vertical direction between a restriction position and a release position,
• the links are arranged to interpose the guide support therebetween and are configured to be rotated by a force applied by the power cylinder,
• the electrode guide is configured to be fixed to the guide support by a biasing force of the biasing member in a state where the tapered portion is fitted into the fitting hole when the displacement member is in the restriction position, and
• the electrode guide is further configured to be released from the lower guide unit when the displacement member is displaced, along with rotation of the links, to the release position against the biasing force of the biasing member.