Transmission apparatus for holding a lock core of a supplemental lock

A transmission apparatus to hold a lock core of a supplemental lock and the transmission apparatus comprising:

• an inner housing having a front, a rear, a lock core chamber defined completely through the inner housing to define respectively a front opening and a rear opening respectively in the front and the rear of the inner housing to hold the lock core, and an inner shoulder formed adjacent to the rear opening;
• an inner disk rotatably mounted in the lock core chamber, abutting the inner shoulder in the inner housing and having an elongated central through hole;
• a lock coupler attached to the inner disk and comprising a rotatable outer disk coupler attached to the inner disk and two lock coupling arms extending from the outer disk coupler toward the inner disk and passing through the elongated central through hole in the inner disk;
• a latch bolt coupler rotated by the lock coupler and comprising a latch coupling arm with an inner end and an outer end being rotated by the lock coupler when the lock coupler is rotated by the lock core;
• a restitution element mounted around the latch coupling arm of the latch bolt coupler to provide a restitution force to hold the latch bolt coupler in place;
• and
• a cover attached to the rear of the inner housing, compressing the restitution element and having a latch coupling arm hole aligned with the outer end of the latch coupling arm to permit the outer end of the latch coupling arm to extend out of the inner housing.