Hybrid vehicle body brings benefits for manufacturers

Hitachi, a major player in the global rail industry, has recently obtained a patent for a new vehicle body design, which combines strength with a lighter-weight design and is easier to manufacture too.

This innovation is part of an extensive, worldwide portfolio of patented technologies, which Hitachi has strategically sought to acquire over time. Recognising that intellectual property protection underlies commercial success, Hitachi has used its patent portfolio to fortify its innovation in the rail industry and protect its market share from being eroded by competitors.

This particular GB Patent 2513817 addresses the problems associated with rail vehicle body weight and its manufacture. For example, heavier vehicles can cause rail track to wear. They can also lead to variable rail track contact and have a limited lifespan. Complex vehicle body structures can also be time-consuming and expensive to manufacture and maintain.

In recent years, rail vehicle bodies have typically been formed using an array of hollow extruded aluminium sections, which are joined together. However, whilst this design is able to provide bodies that are strong and stiff, the processes for fabricating the individual sections and joining them together is both time intensive and costly. Also, there are limited opportunities for reducing weight.

Prior to using the hollow extruded aluminium sections, rail vehicle bodies were manufactured using ribbed extruded sheets and supporting beams. Although being relatively lightweight, this approach nevertheless required further strengthening and stiffening, which resulted in additional reinforcements and fabrication.

To counteract these limitations, Hitachi has obtained patent protection for a new rail vehicle body that has a hybrid design, combining both modular extruded sections and ribbed extruded sheets.

POM 153 aAs illustrated in Figure 2 from the published patent, areas of the rail vehicle body requiring high strength, such as the undercarriage (10) as well as the door or window frames, are manufactured by joining an array of hollow extruded sections (50). Meanwhile, areas bearing a lighter load, such as sidewalls (20) or the roof portion (30), are formed from ribbed extruded sheet (60). The hybrid rail vehicle body therefore has suitable strength and stiffness where necessary, is easy to manufacture and has a reduced overall weight.

It is worth mentioning that the hybrid rail vehicle body protected by the patent shows that patentable inventions do not always need to be “radical”, or “left-field”. In some circumstances, an innovative combination of otherwise known technologies can be enough to satisfy the requirements for patentability. In this case, for example, Hitachi has been able to secure valuable patent protection for a vehicle body with a combination of known features.

As this example demonstrates, it is important for rail innovators not to make assumptions that something is “obvious” and therefore not patentable. Advice may be needed to make this assessment.

In fact, patenting incremental improvements can be an excellent way to extend a patent portfolio for key commercial products, whilst ensuring the latest iterations of commercial products are well protected.

Rosie Hardy is a patent attorney at leading intellectual property firm, Withers & Rogers