Manitowoc Sany patent complaint reveals crawler plans

Manitowoc's complaint focuses on Sany's Auto Counterbalance Equalisation system, used on its 550USt SCC 8500. Manitowoc alleges Sany's system infringes on two patents relating to the VPC system. Manitowoc focuses on the importance of these two patents in allowing a crane to operate with less counterweight, moving ballast in level with the top of the mast when unladen, and out to counterbalance a load when needed. The company says that this reduces operating costs.

Manitowoc filed two patents related to the development of the VPC. In its complaint, Manitowoc explains that the first patent, US 7,546,928, issued in 2009, involves the use of moveable counterweight units to counterbalance a load lifted by the crane. The counterweights can more forward and away from the crane during a pick, move and set operation, to prevent the crane from tipping over, regardless of whether the crane is lifting a load. The counterweight is never positioned on the ground. The system, Manitowoc says, will have more lifting capacity than a crane with stationary counterweight, because the moveable counterweight can generate a higher load moment the further it moves away from the boom of the crane.

The second patent, US 7,967,158, extends on the first. It includes a linear actuation device, Manitowoc explains, for causing the counterweight to move. Another embodiment of the invention allows the counterweight to be moved a greater distance than a stroke of the linear actuation device.

Manitowoc claims that the Sany SCC 8500 infringes the patents' claims. At the time of the launch of the SCC 8500, Sany said "The SANY-exclusive ACE (auto counterbalance equalization) System senses the boom angle and uses hydraulic cylinders to automatically adjust the position of the movable upperworks counterweight.

"The standard ACE System has one upperworks tray with hanging brackets and 20 upper sideblocks. The ACE System design avoids an inefficient carbody counterweight and keeps overall crane weight down.

"The optional UltraLift package includes a second counterweight tray with hanging brackets and 36 upper sideblocks. A second pair of hydraulic cylinders extends the counterweight beam to 52ft 6in. The counterweight beam is supported by a back mast in the UltraLift configuration."

The complaint accuses Sany of misappropriation of trade secrets, saying that this was "a coordinated effort involving former Manitowoc Cranes employee, John Lanning." Lanning came to Sany with four decades of experience in crawler cranes, with Manitowoc, P&H and Link-Belt. Sany described him, in 2010, as having directed design of the 330USt SANY SCC8300, the company's first self-assembling crawler crane, and the new 550USt SCC8500 with its movable counterweight and automatic counterbalance equalization system.

Manitowoc says that the result of the alleged infringement is that Sany will import and sell the Sany SCC 8500 in the United States, on an even larger commercial scale directly in competition with Manitowoc Cranes' domestic products, including two crawler cranes that Manitowoc is currently developing, that use its transformable VPC technology.

Explaining the domestic US industry subject to injury due to the trade secret misappropriation, Manitowoc discusses the importance of its Model 16000 and Model 18000 cranes, their heavy use in constructing wind towers, and some of the recent new features it has introduced to help these cranes compete in the wind energy sector.

Manitowoc says the SCC 8500 is at least competitive with the Model 18000, adding that Sany was able to beat Manitowoc to market with a crawler crane that uses transformable VPC technology, without making the same investments in the US that Manitowoc has.
Manitowoc calls on the ITC to bar Sany from importing into the US products that infringe the two patents in question.