Semaphores on the Kosaka Railway

By Hiroshi Naito

The Kosaka Railway is a short industrial line that transports goods produced at its parent company's Kosaka Refinery to JR Odate Station on the Ou Main Line. The line also used to operate passenger trains until four years ago, but now it operates freight trains only, carrying mostly sulfuric acid in tank cars. The trackage is about 30 km on a single track, with one loop, named Shigenai, between both ends. The subject of this page is Shigenai, which is protected by semaphores associated with the passing signal. Shigenai is now the only signaling site in Japan where an active passing semaphore signal is still in use and token exchange is carried out while the train is in motion.

The freight traffic on the Kosaka Railway is only two round trips a day. The first train leaves Kosaka in the morning being hauled by three center-cab diesel hydraulic locomotives, two of which are helpers attached to the front of the train, because of steep grading between Kosaka and Shigenai. The train stops at Shigenai to uncouple the helpers, which return to Kosaka, and goes to Odate with single engine. The train in return work departs Odate after about one hour, and goes back to Kosaka passing Shigenai. For this train, the passing signal is used to allow the train to go through the loop without stopping. The tokens are exchanged between the running train and the grand apparatus. The afternoon work is the same as in the morning, showing a show of a token exchange on the move.

The down-bound home signals at Shigenai. The yellow blade on the right mast is the passing signal, which serves as a kind of distant signal repeating the aspect of the down-bound starter. When an approaching train is allowed to pass the loop with the starter cleared, the passing signal blade goes into the off position; otherwise it remains in the on position.

The Shigenai station signboard on the platform viewed through the signal wire strung high above the ground. A hoop is already in position to be picked up by the passing train.

Tablet blocking instruments in the station building. The one on the right is for blocking the Shigenai to Kosaka section, while the one on the left is for the Shigenai to Odate section. These instruments were made by Nippon Signal Co. in 1961. Hoops attached to the leather pouches are prepared.

The Shigenai Station building with a wooden cabin at rear where the signal lever fram is installed. The spiral device in front is the tablet catcher to which the train driver throws the hoop.

The down-bound starter signals at Shigenai viewed from the platform.

The signal lever frame, which is fitted with 11 levers corresponding to eight routes plus two passing signals including one switch point lever. Here, three levers are reversed, for the down-bound main home, down-bound main starter and down-bound passing signals.

A view of Shigenai station looking at the up-bound direction from the station building.

A down-bound freight train passes by the home signal in the late afternoon light. Both home and passing blades are off, indicating "passing clear."

A token exchange on the move. The train driver is about to pick up the next token attached to the hoop. The previous token has already been thrown.

The home signals at Odate installed on the gantry. The level crossing in front is manually operated.

A starter semaphore stands alone at the exit of Kosaka yard.

A Kosaka Railway triple-header tanker train descending the grade to Shigenai after having crossed over the summit. The motive power are DD-13s.