Views: 0 Author: Site Editor Publish Time: 2026-01-06 Origin: Site
The electrical equipment that enables electric traction locomotives to obtain electrical energy from the overhead contact line is installed on the roof of the locomotive or EMU. The pantograph can be divided into single-arm and double-arm types. Both consist of components such as the sliding plate, upper frame, lower arm rod (for double-arm pantographs, the lower frame is used), base frame, lifting spring, transmission cylinder, and support insulator. The rhombic pantograph, also known as the diamond pantograph.
The smoothness of the current passing through the contact surface between the contact wire and the sliding plate of the pantograph is related to the contact pressure between the sliding plate and the contact wire, the transition resistance, and the contact area. It also depends on the interaction between the pantograph and the overhead line.
The compressed air enters the transmission cylinder uniformly through the electro-pneumatic valve. The piston of the cylinder compresses the lowering spring inside the cylinder. At this time, the raising spring causes the lower arm rod to rotate, lifting the upper frame and the sliding plate. The pantograph rises at a constant speed and slows down gradually when approaching the contact wire, then quickly contacts the contact wire.
The compressed air in the transmission cylinder is rapidly discharged to the atmosphere through the pantograph buffer valve. Under the action of the lowering spring, it overcomes the force of the raising spring and causes the pantograph to rapidly descend, detaching from the contact network.
The double-arm type overhead contact system is the most traditional type of pantograph, also known as the "diamond" type pantograph, named so because of its diamond shape. However, due to higher maintenance costs and the risk of breaking the contact wire during faults, some newly manufactured railway vehicles have now switched to single-arm pantographs; and some railway vehicles (such as the Shinkansen 300 series) have been transformed from the original double-arm pantographs to single-arm pantographs.
In addition to the double-arm type, there is also the single-arm type overhead contact system, also known as the "Z" (ㄑ) or "T" (T) shaped pantograph. The advantage of this type is that it is quieter than the double-arm type pantograph and is less likely to break the contact wire during faults, making it a more common type of pantograph. And depending on the design of each railway vehicle manufacturer, there may be some differences in the design of the pantograph.
Apart from the above two types of pantographs, there are also some pantographs with vertical design, also known as "T" (T) shaped (also called wing-shaped) pantographs. Their low wind resistance characteristic is particularly suitable for high-speed travel to reduce noise during driving. Therefore, this type of pantograph is mainly used in high-speed railway vehicles. However, due to high costs, vertical pantographs have no longer been used (during the renovation of the Japanese Shinkansen 500 series, vertical pantographs were changed to single-arm pantographs).
The sixth-generation president of Japan's Okayama Electric Railways, Shishin Ryuhei, invented it in 1951 and is also known as "Okayama type" or "Okayama rail type".
