New Shangcheng Meter Technology Co., Ltd. , http://www.chinapowermeter.com
The secondary balance shaft is used to suppress the secondary inertia force of the in-line 4-cylinder engine, and one of the two balance shafts is driven by a drive gear that is pressed into the crankshaft, and the other one is driven by the gear.
Originally, these gears were made of steel and required quenching and grinding processes. The newly developed secondary balance shaft resinizes the two gears of the balance shaft. One is a gear driven by a crankshaft and the other is a gear of a balance shaft on the opposite side. Both of the gears that are engaged with the metal gear are resinized.
The gears used were reinforced by immersion in aramid fibers in a thermosetting polyaminoamide. This gear is formed by cutting a round molded article. By resinizing, in addition to reducing the weight of the gear by half, the backlash tolerance is also increased, which reduces the adjustment work during installation, thereby reducing the cost. In addition, the common rotating area - near 2000 rpm noise can be reduced by about 15 dB.
New Kobe Electric exhibited low noise resin gears
The new Kobe Electric exhibited the resin shaft of the secondary balance shaft at the "People and Car Technology Exhibition" (May 23-25, 2007, Yokohama Convention and Exhibition Center). The gear has been adopted by the 2.4L displacement "2AZ-FE" engine equipped with Toyota "Estima".